Novatel Wireless NRM-3800 CDPD Data Transceiver User Manual Vespa AT Command Set Reference Guide 0 1

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AT Command Set

Reference Guide

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Expedite and Merlin

Wireless IP Modems

PS-01016529

UNRELEASED

Release 2.1

Friday, May 7, 1999

The information disclosed herein is the exclusive property of NOVATEL WIRELESS TECHNOLOGIES

LTD. and is not to be disclosed without the written consent of NOVATEL WIRELESS TECHNOLOGIES

LTD. No part of this publication may be reproduced or transmitted in any form or by any means including

electronic storage, reproduction, execution or transmission without the prior written consent of NOVATEL

WIRELESS TECHNOLOGIES LTD. The recipient of this document, by its retention and use, agrees to

respect the security status of the information contained herein.

This document is intended for limited circulation.

The information contained in this document is subject to change without notice and should not be

construed as a commitment by NOVATEL WIRELESS TECHNOLOGIES LTD. unless such commitment

is expressly given in a covering document.

REVISION HISTORY

REV# ECO# EFF. DATE DESCRIPTION PREPARED APPROVED

1 99010 990505 Initial release. D. Barber S. Smilar

2.0 99024 990705 Updated to include new features for

TV01-02, including Friends Mode,

Quiet mode and Stack Check

features.

D. Barber S, Smilar

2.1 Added registration mode and out-of-

service sleep commands. Added

index of AT commands.

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Table of Contents

INTRODUCTION.................................................................................................................................................... 6

Scope ....................................................................................................................................................................... 6

PHYSICAL INTERFACE ....................................................................................................................................... 7

Protocol................................................................................................................................................................ 7

Software Interface .................................................................................................................................................. 8

AT Command Mode........................................................................................................................................... 8

Command format................................................................................................................................................ 8

Result format....................................................................................................................................................... 8

Data Mode Description ...................................................................................................................................... 9

Internal Stack Description ............................................................................................................................... 10

UDP Mode Description .................................................................................................................................... 11

TCP Mode Description..................................................................................................................................... 12

DTR Control Description.................................................................................................................................. 14

Push Technology.............................................................................................................................................. 15

Slip Mode........................................................................................................................................................... 16

Point to Point Protocol (PPP).......................................................................................................................... 17

Data Transmission Mode ................................................................................................................................18

Data Reception Mode ...................................................................................................................................... 19

Sleep Mode Description................................................................................................................................... 20

Sleep Mode Feature Enable/Disable ............................................................................................................. 21

Out-of-service Sleep Mode ............................................................................................................................. 22

Power-up Default Mode................................................................................................................................... 25

Set Hardware Configuration............................................................................................................................ 26

Profile Configuration Commands ................................................................................................................... 27

Program Mode .................................................................................................................................................. 28

Local Echo......................................................................................................................................................... 29

Response Format............................................................................................................................................. 30

Programmable I/O............................................................................................................................................ 31

Soft Reset.......................................................................................................................................................... 33

Side Preference................................................................................................................................................ 34

Password........................................................................................................................................................... 35

Escape Sequence ............................................................................................................................................ 36

Hardware Flow Control.................................................................................................................................... 37

Disconnect (Hang-up)...................................................................................................................................... 38

Restore Factory Defaults................................................................................................................................. 39

Line Speed and Format................................................................................................................................... 40

View Active Profile............................................................................................................................................ 42

Save Current Profile......................................................................................................................................... 43

Destination IP Address/Port............................................................................................................................ 44

Debug Mode...................................................................................................................................................... 45

Auto Answer (TCP Listen)............................................................................................................................... 46

Connection Establishment Time-out.............................................................................................................. 47

Data Forwarding Idle Time-out....................................................................................................................... 48

Data Forwarding Idle Character ..................................................................................................................... 49

UDP Half Open Mode ...................................................................................................................................... 50

Status Reporting............................................................................................................................................... 51

Local IP Address/Port ...................................................................................................................................... 53

Service ID Preference...................................................................................................................................... 55

Channel Scan Mode......................................................................................................................................... 56

Channel List ...................................................................................................................................................... 58

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Service ID Preference...................................................................................................................................... 59

CDPD Operating Version ................................................................................................................................60

Wireline Compatibility ...................................................................................................................................... 61

Set DTR Control ............................................................................................................................................... 62

DTR Mode Setting............................................................................................................................................ 63

DSR Control Setting......................................................................................................................................... 64

TCP Timer......................................................................................................................................................... 65

Identity Registers.............................................................................................................................................. 66

Description:........................................................................................................................................................ 66

Query Network Connection Status................................................................................................................. 67

Last network registration error code .............................................................................................................. 70

Authentication Parameter................................................................................................................................71

Query Current RSSI Value.............................................................................................................................. 72

Query Current Block Error Rate (BLER) ....................................................................................................... 73

Current RF Channel in use ............................................................................................................................. 74

Cell Site ID in Use ............................................................................................................................................ 75

Area Color Code in Use................................................................................................................................... 76

Power Level Query........................................................................................................................................... 77

Symbol Error Rate Query................................................................................................................................78

Power Product................................................................................................................................................... 79

Authentication Failures Query......................................................................................................................... 80

Dial (Connection Setup)................................................................................................................................... 81

ADC Monitoring................................................................................................................................................. 83

Ping Command................................................................................................................................................. 86

Power Boost...................................................................................................................................................... 87

Message Waiting.............................................................................................................................................. 88

Internal MRU Setting........................................................................................................................................ 89

TCP Suspension Enable ................................................................................................................................. 90

Call Progress Result Mode ............................................................................................................................. 91

Answer ............................................................................................................................................................... 92

Telnet Echo ....................................................................................................................................................... 93

Modem Identification........................................................................................................................................ 94

Friends Mode .................................................................................................................................................... 95

Stack Check ...................................................................................................................................................... 97

Quiet Mode........................................................................................................................................................ 98

Registration Mode ............................................................................................................................................ 99

Fixed Parameters........................................................................................................................................... 100

Unsupported Commands .............................................................................................................................. 101

Unsupported Functions.................................................................................................................................. 101

Appendix A: AT Command Set Quick Reference....................................................................................... 102

Index of AT Commands..................................................................................................................................... 106

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INTRODUCTION

This document is intended to provide the serial AT Command Interface provided by Expedite

Wireless IP Modem for embedded OEM applications. The Expedite Wireless IP modem provides

a connection-oriented service so that existing OEM application protocols can be used. In addition,

the capability to switch the unit to Serial-Line-Internet-Protocol (SLIP) or Point-to-Point-Protocol

(PPP) modes are provided so that new protocols can be developed within the OEM application.

This document describes the Novatel Wireless Expedite Wireless IP Modem. The Expedite

Wireless IP modem is an OEM-module designed for integration into a host product to provide

wireless data communication capability via the CDPD (Cellular Digital Packet Data) Network. It

features internal TCP and UDP IP stacks as well as SLIP and PPP protocols for an external stack

and provisions for using “Sleep Mode” to extend the operating time of battery powered devices.

Scope

The scope of this document is limited to providing information on the various AT commands which

can be used on Novatel CDPD products as well as a brief summary of some of the standard AT

commands which are not supported. Internal design issues, detailed operating instructions and

cost information is not included in this document.

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PHYSICAL INTERFACE

Protocol

CDPD System Specification Part 400 Version 1.1 (CDPD Forum Inc.) This is the protocol stack

for the Expedite Wireless IP Modem:

sical

MAC

MDLP

SNDCP

SLIP PPP UDP TCP

AT Interface

Communication Driver

CDPD

ers

Host

OEM

lication

ers

To Host

The Expedite Wireless IP Modem does not support V.42 compression in SNDCP.

The TCP/UDP interface is capable of supporting up to 3 sessions simultaneously1.

The AT-command set described herein is derived from “CDPD Implementor Guidelines”, Release 1.12. It

contains a subset of the commands described in Part 2014 that are supported by the Novatel Expedite

Wireless IP Modem.

For the purposes of this specification, “NRM” refers to the Novatel Expedite Wireless IP Modem; “Host”

refers to the OEM application controller.

1 This is provided to solve the problem presented by delays encountered when closing a TCP session. That is, in order to process

Host transactions in rapid succession (and since it is required to establish a new TCP session for each transaction) it is

necessary to establish a new TCP session before the previous one has had a chance to close.

2 CDPD Forum makes no representations about the suitability of any material, comprising the CDPD system specification (or any

derivative work incorporating any element thereof) for any purpose; it being provided “as is” and without any warranties

whatsoever, express or implied. The CDPD Forum shall not be responsible for any damages of any kind related to the use of

the CDPD system specification (or any derivative work incorporating any element thereof), including without limitation,

actual, direct, indirect, incidental, consequential, special, or general damages.

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Software Interface

A brief description of those functions specific to the Expedite Wireless IP Modem is described here.

AT Command Mode

AT commands and responses are active in command mode only; as determined by the state of the DSR

line. Command mode behavior conforms to ANSI/TIA/EIA-602-1992 section 5, with the limitations stated

below. The AT command set is a subset of the AT command set defined in ANSI/TIA/EIA-602 and in the

CDPD System Specification Part 2014 Version 1.1, section 4.

Command format

Note the following limitations:

- The termination character is fixed as CR (ASCII 13).

- Command line editing is supported (BS, ASCII 08 only).

- Command line repeats (A/) is not supported.

- The rules described below for buffering and flow control also apply to command mode. The Host

should not transmit a single AT command which exceeds the buffer length (256 characters). In

addition, the Host should wait until all responses associated with an AT command string have been

received before issuing another AT command.

- Abortion of command-in-progress is not supported.

- Default command parameters are accepted for the last command on a command line only.

Result format

The format of result code responses is determined by the ATV command setting.

In terse mode, the result code is sent as a single ASCII character followed by a carriage return (ASCII 13)

character.

In verbose mode, a descriptive text message is sent followed by a carriage return. The following result

codes are emitted by the NRM:

Terse

mode Verbose mode Description of Command

0 OK Command accepted.

1 CONNECT Connection established.

2 RING Network origination indication.

3 NO CARRIER Connection terminated, not established or command aborted.

4 ERROR Invalid command parameter/state (e.g. DTR must be active before ATD can be

accepted.)

5 NO SOCKETS No free TCP sockets within S7 seconds.

6 NO DIALTONE CDPD link not established.

7 BUSY Refused by destination or network, OR: Operation in progress.

8 NO ANSWER No response received from the destination within S7 seconds.

9 HELLO Issued at power on/reset.

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Data Mode Description

The modem contains an integrated TCP/IP protocol stack. It is accessed via AT commands that put the

modem into either a TCP or UDP data communications mode. If the application host contains a TCP/IP

stack, PPP or SLIP can be used to transfer IP packets between the application host and the modem.

The Data Terminal Ready (DTR) line is used by the modem as a qualifier for its operation in a data mode,

TCP, UDP, SLIP or PPP. The DTR line is to be asserted before entering a data mode to indicate to the

modem that the host computer is available for operation. The DTR line is de-asserted to terminate a data

session. The modem will not sustain a data mode session without DTR being active. The use of DTR

can be overridden by setting register S211 to 1: the equivalent of asserting DTR permanently.

The DSR Signal is driven by the modem to indicate the existence of a data session. When the local host

asserts DTR, the modem will respond with the DSR signal to indicate that the modem has entered data

mode. DSR is de-asserted to indicate that the modem has exited data mode.

The NRM provides Host and Network originated access to the connection-oriented service using TCP/IP.

Host origination is accomplished via the DIAL (ATDT) command. Upon successful completion of the DIAL

command (i.e. CONNECT result code), the NRM switches to TCP-Data mode. DTR must be asserted

prior to issuing the ATDT, ATDP, AT\ASLIP or AT\APPP. If this is not followed the modem will not engage

the session in a manner where it can be sustained. The NRM signals a network origination to the Host

using the RING result code. Failure to have DTR asserted while in “Listen” mode, network origination, will

result in a dropped session. The PAD functions are active during TCP-Data mode only, however, the

data buffering functions apply in all modes.

For Listen mode applications, the modem must see DTR asserted when the TCP Session request is

received. If DTR is not asserted the session request will be rejected. When the DTR signal is asserted,

the modem will issue a RING followed by a CONNECT to indicate the beginning of an incoming data

session. Here RING indicates the source of the session as being a remote server while the CONNECT

indicates the transition from AT Command mode to Data mode. . In this mode, the NRM will “Listen” for

TCPP packets with port numbers which match that specified with the NRM’s IP address (re: S110). Any

TCP packets received in AT-CDPD mode, or packets received in TCP-Data mode without a matching port

number, are rejected by the NRM with no indication to the Host. DTR can be used to terminate the

session or the remote server can initiate the termination.

A session may be terminated by the Host de-asserting the DTR line. The remote host may also terminate

a session. Connection status is maintained on the DSR line. Once the session has been terminated, the

NRM returns to AT-CDPD mode. Note that session termination is the only method to return to AT-CDPD

mode3.

For UDP/IP, a connection-oriented service is “fabricated” within the NRM. The DIAL command (ATDP) is

used to place the NRM into UDP-Data mode. In this mode, the NRM will “Listen” for UDP packets with

port numbers which match that specified with the NRM’s IP address (re: S110). Any UDP packets

received in AT-CDPD mode, or packets received in UDP-Data mode without a matching port number, are

rejected by the NRM with no indication to the Host. In UDP-Data mode, the port number for transmitted

UDP packets is specified with the destination address associated with the DIAL command. Only the Host

Origination and Host Termination scenarios described above apply to UDP operation. The DTR and DSR

lines, and the PAD functions, operate as in TCP-Data mode.

3 The Hayes compatible escape sequence is not supported.

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Internal Stack Description

IP (Internet Protocol) is the basic network protocol that routes packets on an IP network. CDPD networks

and the Internet are IP networks. Transport protocols deliver packets between applications. Transport

protocols use the IP service to deliver data packets between network devices.

In order for an application to communicate across a network, it will first open a port on the local device.

The IP address of the local device and this port number becomes the unique address for this application,

and is sometimes referred to as a socket. When the local application communicates with a distant

application, it will send a packet addressed to the IP address and port number of that remote application.

This address is the destination address of the packet. The packet will also contain the source address, the

IP address and port number of the local application. The remote application may use the source address

of the packet received to communicate back to the local application.

There are two common transport protocols used in TCP/IP networks:

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UDP Mode Description

User Datagram Protocol is a basic transport protocol that provides a best-effort, connectionless delivery

service with minimum overhead. The protocol does not guarantee delivery of packets. There is no

checking or retransmission of the data packets. It does provide minimum overhead as it only adds the

source and destination port numbers to the header. Since the protocol is unreliable, the application must

provide checking, acknowledgments and retransmissions if the data is critical. In many applications, the

data is not critical because updates are sent periodically and occasional losses can be tolerated.

UDP sessions may be originated by the local application host or by the network. The DTR signal must be

asserted or S211=1 (pretend DTR is always asserted) for the unit to enter into a data communications

session. The session is terminated by dropping DTR or resetting the unit.

UDP Modes of Operation

Command: ATS82 = <mode>

Where <mode> = Timer value in seconds

0 = Regular mode

1 = Not used (reserved)

2 = Half-Open mode

Originating a UDP Session

A session is originated by the application host issuing the ATD (Dial) command:

ATDPnnn.nnn.nnn.nnn/ppppp

ATDP specifies a UDP session. nnn.nnn.nnn.nnn is the destination IP address and ppppp is the

destination application port number. If no port is specified then a port number of 0 is assumed. It should

be noted that UDP and TCP make extensive use of port numbers, please be aware that the modem will

use the port number as a criteria for accepting and passing data to the host application.

CONNECT [terse 1] result code will be issued and all ensuing data sent from the host application will be

assembled into a UDP packet and transmitted to the destination application.

ERROR [terse 4] result code will be generated if the modem is not currently registered on a CDPD

network.

PAD (Packet Assembly and Disassembly) function will transmit data when the inter-character idle time-out

occurs or when the PAD buffer is full. (256 or 512 bytes). The idle time-out is specified in register S50 in

1/10 seconds.

Receiving Data - Once the session is started, any packets sent to the modem's IP address with the port

number specified in register S110 will be processed and the data portion will be transmitted over the serial

link to the host application. Any packets received with a different port number specified will be discarded.

Termination - The session is terminated by dropping DTR or resetting the unit.

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TCP Mode Description

Transport Control Protocol, is a reliable, connection-oriented transport protocol that uses

acknowledgments and retransmissions to guarantee delivery. This is an obvious advantage for

applications where the data is critical and the application cannot provide the required reliability. There is

more overhead in the protocol to provide this reliability, making it less efficient than UDP. For larger data

transfers, TCP is the easiest protocol to use to get reliable service.

TCP sessions may be originated by the local application host or by the network. The DTR signal must be

asserted or S211=1 (pretend DTR is always asserted) for the unit to enter into a data communications

session. The session is terminated by powering the modem off, dropping DTR or by the remote host

terminating the connection. If the session is terminated by a power down, the remote host may not tear

down its part of the session properly, leaving the remote host waiting for further information for that

session. This can pose problems for some applications. Care in session tear down is essential for

reliable operation.

TCP Modes of Operation

TCP Listen mode is established by having S0=1 when the modem powers up. . The port specified in

S110 will be used for the TCP Listen mode. The DTR signal must be asserted or S211=1 (ignore signal on

DTR pin and proceed as if DTR is always asserted) for the unit to enter into a data communications

session. When a connection request for the correct port is received by the modem, the modem will

establish the connection notify the local host with:

Verbose Terse

RING 2

CONNECT 1

and begin the TCP session.

Termination - A TCP connection is terminated by dropping DTR, or by the remote end of the TCP

connection terminating the session.

Originating a TCP Session

A session is originated by the host application by issuing the ATD (Dial) command:

ATDTnnn.nnn.nnn.nnn/ppppp

ATDT specifies a TCP session. nnn.nnn.nnn.nnn is the destination IP address and ppppp is the

destination application port number. The modem will attempt to establish a connection with the destination

host. If it is successful, a CONNECT [terse 1] result code will be issued and all ensuing data sent from the

app host will be assembled into a TCP packet and transmitted to the destination application.

ERROR [terse 4] result code will be generated if the modem is not currently registered on a CDPD

network.

Connection Failure will be signaled by a BUSY [terse 7] result code, and may be caused by one of the

following:

- Wrong IP address or port number

- The destination device does not have a TCP Listen process open on the port specified.

- The destination host already has a connection established with another client on the specified port.

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- Connection failed to complete within the time specified in register S7 (sec). Normal values are about

30 seconds, but is very dependent upon the application requirements. Many applications, which

provide their own time-out for connection failure, will have this value set to 60+ seconds.

PAD (Packet Assembly and Disassembly) function will transmit data when the inter-character idle time-out

occurs or when the PAD buffer is full. (256 or 512 bytes). The idle time-out is specified in register S50 in

1/10 seconds.

Receiving Data - Once the session is started, any packets sent to the modem's IP address with the port

number specified in register S110 will be processed and the data portion will be transmitted over the serial

link to the host application. Any packets received with a different port number specified will be discarded.

Termination - A TCP connection is terminated by dropping DTR or by the remote end of the TCP

connection terminating the session.

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DTR Control Description

The Data Terminal Ready (DTR) line is used by the modem as a qualifier for its operation in a data mode,

TCP, UDP, SLIP or PPP. The DTR line is to be asserted before entering a data mode to indicate to the

modem that the host computer is available for operation. The DTR line is de-asserted to terminate a data

session. The modem will not sustain a data mode session without DTR being active. The use of DTR

can be overridden by setting register S211 to 1: the equivalent of asserting DTR permanently.

The DSR Signal is driven by the modem to indicate the existence of a data session. When DTR is

asserted by the local host, the modem will respond with the DSR signal to indicate that the modem has

entered data mode. DSR is de-asserted to indicate that the modem has exited data mode.

For Listen mode applications, the modem must see DTR asserted when the TCP Session request is

received. If DTR is not asserted the session request will be rejected. When the DTR signal is asserted,

the modem will issue a RING followed by a CONNECT to indicate the beginning of a incoming data

session. Here RING indicates the source of the session as being a remote server while the CONNECT

indicates the transition from AT Command mode to Data mode. . In this mode, the NRM will “Listen” for

TCPP packets with port numbers which match that specified with the NRM’s IP address (re: S110). Any

TCP packets received in AT-CDPD mode, or packets received in TCP-Data mode without a matching port

number, are rejected by the NRM with no indication to the Host. DTR can be used to terminate the

session or the remote server can initiate the termination.

A session may be terminated by the Host using the DTR line. The remote host may also terminate a

session. Connection status is maintained on the DSR line. Once the session has been terminated, the

NRM returns to AT-CDPD mode. Note that session termination is the only method to return to AT-CDPD

mode4.

The DTR line de-asserted can also be optionally used to power the modem off in addition to the

termination of the session. If the S211 register is set to 4, then the de-asserting of the DTR line will make

the modem terminate any current data session, perform a de-registration with the network and power itself

off.

4 The Hayes compatible escape sequence is not supported.

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Push Technology

To receive data while the modem is unattended by the host, the modem has been incorporated with the

means to receive the data packet, determine the type of message and the source IP address. This push

technology feature can be enabled or disabled by setting or resetting register S250. The modem can

signal the host that there are messages queued up, waiting to be retrieved by the host, using any or all of

the following signals. The “message waiting” signal can be asserted when a message arrives and will be

de-asserted when all messages have been retrieved or deleted. In the case of multiple messages, the

“message waiting” signal will be asserted when the first arrives and will only be de-asserted when all

messages have been retrieved. Another signal, the “alert” signal, can also be used to provide a 500msec

pulse to the host on its associated pin for each message that arrives. These signals can be made

available on any of the programmable pins of the interface. Their assignment is made using the

programmable GPIO features of the Expedite Wireless IP Modem.

The modem can hold up to 4 messages, determined by reading register S251, before the buffer overflows

and message data is lost. When the host accesses the modem to retrieve the stored messages, the host

first determines which messages it wants to retrieve based upon the source IP address. The host can

discard messages by setting register S254. This will cause the current message to be flushed from the

queue and the next message made available to the host.

PUSH Technology Enable

ATS250? Query Wake Up Protocol State

ATS250=1 Enable Push Technology

ATS250=0 Disable Push Technology

ATS251? Query Number of Pending Messages

Response [0..4]

ATS252? Query First Push Message

Response [IPaddress/port]

Format nnn.nnn.nnn.nnn/xxxxx

ATS253? Query Type of First Push Message

Response [0, 1] 0 indicates UDP, 1 indicates TCP

ATS254=1 Discard Current Message

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Slip Mode

Description:

The command to enter Serial Line Internet Protocol mode (SLIP) is used when an external stack

configuration is needed. SLIP is useful if the stack resides in the host computer, multiple sessions and

complete control over all aspects of each session can be obtained. SLIP is one of the more common

protocols used for splitting the functionality between the modem and the host. SLIP does, however,

require certain parameters to be set up prior to activating a session. SLIP does not extract the IP address

from the modem. This must be set up in dial-up-networking before starting. SLIP is less flexible than

Point to Point Protocol (PPP) which is quickly winning over most users.

The SLIP session is usually controlled by DTR, unless the modem has been configured to ignore DTR by

programming register S211. DTR, when used, must be asserted to initiate a session and de-asserted to

terminate a session. If the modem has been programmed not to use DTR Control, then the command

AT\ASLIP can be sent without asserting DTR. To exit SLIP in this case, the host must either power down

the modem or use the escape sequence. To terminate a SLIP session, DTR must be de-asserted or the

escape sequence can be activated or the modem can be powered down.

Format:

AT\ASLIP The command to enter SLIP mode

Validity:

Slip can only be entered from Command Mode. In Program or Diagnostic modes, the modem is not

actively connected to the network.

Other Considerations:

While a modem can enter SLIP mode from command mode at any time, the intent of SLIP is to connect to

the network. Until there is a network connection established and the modem has registered, it is better to

delay entering SLIP mode as you may report errors that will only persist until the modem registers. It is

generally recommended that the host check the status of the modem before proceeding with a SLIP

connection. The Status can be checked using the “ATS57?” command.

Related Topics:

Enter PPP Mode, DTR Control, Program Mode, Data Mode, Diagnostic Mode. Checking Status, Escape

Sequence

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Point to Point Protocol (PPP)

Description:

The command to enter Point to Point Protocol mode (PPP) is used when an external stack configuration is

needed. PPP is useful if the stack resides in the host computer, providing multiple sessions and complete

control over all aspects of each session. PPP is quickly becoming the new standard for dial-in-networking.

PPP provides more flexibility and less items that need to be explicitly set.

The PPP session is usually controlled by DTR, unless the modem has been configured to ignore DTR by

programming register S211. DTR, when used, must be asserted to initiate a session and de-asserted to

terminate a session. If the modem has been programmed not to use DTR Control, then the command

AT\APPP can be sent without asserting DTR. To exit PPP in this case, the host must either power down

the modem or use the escape sequence. To terminate a PPP session, DTR must be de-asserted or the

escape sequence can be activated or the modem can be powered down.

Format:

AT\APPP The command to enter PPP Mode

The response will be CONNECT or ERROR

The alternate command to use is SERVER

The response will be CLIENT

Validity:

PPP can only be entered from Command Mode. In Program or Diagnostic modes, the modem is not

actively connected to the network.

Other Considerations:

While a modem can enter PPP mode from command mode at any time, the intent of PPP is to connect to

the network. Until there is a network connection established and the modem has registered, it is better to

delay entering PPP mode as you may report errors that will only persist until the modem registers. It is

generally recommended that the host check the status of the modem before proceeding with a PPP

connection. The Status can be checked using the “ATS57?” command.

An alternate method of entering PPP mode is to send the word CLIENT to the modem. The modem will

respond with SERVER. This is NOT an AT command. It is neither preceded by an "AT" nor succeeded

by a CR. Exiting PPP mode is performed using the DTR control signal.

Related Topics:

SLIP Mode, DTR Control, Program Mode, Data Mode, Diagnostic Mode. Checking Status

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Data Transmission Mode

Packet Assembly

The NRM provides a local Packet Assembly and Disassembly (PAD) function. For transmission,

the character stream from the Host is assembled into packets for RF transmission under the

following conditions:

-Idle time-out: If the time between successive characters exceeds the time interval specified in

Buffering and Flow Control

The NRM has an input data buffer which is intended to be set larger than the longest transmit

message used by existing protocols in the Host. The size of this buffer is 578 characters.

If hardware flow control is disabled and, the NRM is formatting and transmitting data blocks

associated with a packet, the Host should not send additional data as this may cause input buffer

overflow. Buffer overflow will result in a loss of data with no indication to the Host. In order to

avoid data loss, it is recommended (and anticipated) that the Host application protocol operates

using a half-duplex ACK/NAK protocol. It should be expected that the Host acknowledgment

time-out should be set greater than that required for circuit-switched modem configurations. This

is to account for propagation delays through the NRM, CDPD base station and CDPD and Internet

networks.

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Data Reception Mode

Packet Disassembly

The NRM begins transmitting the character stream associated with a received packet to the Host

as soon as all the associated blocks have been received and processed.

Buffering and Flow Control

The NRM has an output data buffer which is intended to be set larger than the longest receive

message used by existing protocols in the Host application. The size of this buffer is 2144

characters.

When the NRM is sending the characters associated with a received packet to the Host, the

remote host processor should not send additional data as this may result in output buffer overflow.

NRM buffer overflow shall result in a loss of data with no indication to the Host or remote host. In

order to avoid data loss, it is recommended (and anticipated) that the Host application protocol

operates using a half-duplex ACK/NAK protocol. The remote host acknowledgment time-out

should be lengthened as described above.

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Wireless IP Modems

Sleep Mode Description

Sleep mode can be activated by sending the commands AT#ZZ=1, AT#ZZ=2 or deactivated by

the command AT#ZZ=0. Changes must be entered in program mode. The module should be

reset after changing the sleep mode activation since the module will have registered and informed

the network that it has sleep mode or not. The module will enter sleep mode, if activated, after the

inactivity timer has expired and a Network TEI notification message has been received by the

modem.

In areas with low signal strength or where the signal strength varies to a high degree, the unit may

not enter sleep mode in a regular fashion. The unit must have conditions where the unit can

decode the TEI notification messages from a reliable signal.

No notification message or signal is given to the host that sleep mode is engaged. The host must

assume that if the modem has been inactive for more than the number of seconds specified in the

inactivity timer that the modem has gone to sleep.

To wake the modem up from sleep mode, the wake-up signal can be asserted for a minimum of

10 ms or a break character of 20 ms in duration followed by a 2 ms pause or 2 character spaces

at 19200 bps can be sent. The module will de-assert CTS when entering sleep mode to inhibit the

host from sending data but will periodically assert CTS and check for incoming serial data from

the host to prevent any loss of data.

No indication is given to the module that the host is in sleep mode. The module will assume the

host is sleeping if the module is sleeping and send a break character to initialize communications

with the host.

There are two types of sleep mode implemented for this product:

i. Normal – in normal sleep mode, the modem will attempt to maximize its sleep time based

on the configuration of the network where it has registered. Practically, this means that if

the network supports a sleep time of 60 seconds, and allows 5 TEI notifications to be

missed without penalty, the modem could theoretically sleep for a minimum of 4 minutes.

ii. Short – in short sleep mode, the modem will attempt to sleep in short bursts of 5 seconds

and awaken to allow communication from the host. In this mode, CTS would normally be

deasserted so hosts would not normally attempt to send data until the CTS is asserted

again in 5 seconds when the modem wakes up for 400msec. This is the same operation

as in the NRM6812 products when AT#ZZ=2 and has been maintained for backward

compatibility.

Related Topics:

Sleep Mode Feature Enable/Disable

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Sleep Mode Feature Enable/Disable

Description:

This command permits the user to define what sleep mode the modem should use. Since various

applications and host computers have different requirements for communicating with a modem that

utilizes sleep mode, this command encompasses several different options that should satisfy any

application. If sleep mode does not appear to work with your application, please contact Novatel Wireless

for assistance. The default setting for this mode is off.

Format:

AT#ZZ? Sleep status query command

AT#ZZ=0 Disable sleep feature

AT#ZZ=1 Enable Long cycle sleep

AT#ZZ=2 Enable short cycle sleep

Validity:

Changes must be entered in program mode.

Other Considerations:

See the sleep mode description.

Related Topics:

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Out-of-service Sleep Mode

The modem must be registered and within a reliable coverage area before it can actually go to

sleep for standard sleep mode. This means that the modem cannot sleep and will be in a higher

battery discharge state at all times that the modem is outside of CDPD coverage. The Out-of-

service Sleep Mode allows the modem to go to sleep during periods of no coverage. The modem

will sleep for some (usually relatively long) period and wake occasionally to see if it has returned

to a coverage area. The goal is to give the modem a battery life approaching that of standard

sleep mode when within CDPD coverage.

Out-of-service sleep mode is activated by sending the AT#NSZZ=1 command or deactivated by

sending the AT#NSZZ=0 command. This change must be saved with the AT&W command, and

the module must be reset before this change will take effect.

Following a loss of signal, the modem will make several attempts to find service on the currently

registered side before deciding that it is no longer registered and that it must search both sides for

service. Once this has occurred, or following modem initialization under no service conditions, the

modem will continue to search for a valid CDPD signal for the complete scan period. If no service

is found the modem will sleep for the sleep cycle length less the time that it was awake for the

search. After this sleep interval, the modem will wake for a brief search. If no service is found, it

will sleep again for the sleep cycle length less the brief scan period. This cycle continues with one

scan period in each cycle count periods being a complete scan. If the modem finds service and

registers during one of the scans, the out-of-service sleep mechanism is reset and waits for the

next time that service is lost.

To prematurely wake the modem up from out-of-service sleep mode, the wake-up signal can be

asserted for a minimum of 10 ms. The module will de-assert CTS when entering sleep mode to

inhibit the host from sending data but will periodically assert CTS and check for incoming serial

data from the host to prevent any loss of data.

Description:

These commands permit the user to define what the parameters of out-of-service sleep mode and to

enable or disable the operation of this mode. If out-of-service sleep mode does not appear to work with

your application, please contact Novatel Wireless for assistance. The default setting for this mode is off.

Format:

AT#NSZZ Out-of-service Sleep status query command

AT#NSZZ=0 Disable out-of-service sleep feature

AT#NSZZ=1 Enable out-of-service sleep feature

AT#NSZZTM=p,b,c,n Configure out-of-service sleep feature

p = sleep cycle length in seconds. This is the interval

between successive wakeups.

b = brief scan period in seconds. This is the time that

the modem will be awake for most of its waking intervals.

It is intended to be a brief look at the hot list of the

preferred side.

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c = complete scan period in seconds. This is the time

that the modem will be awake once in each cycle count

sleep cycles. It is intended to be long enough for the

modem to register on the network if a channel is

available on either side; that is, time to completely search

the cellular environment for a channel to register on.

n = cycle counts in units. One waking interval in “cycle

count” wakeups will be a complete scan. All other

waking intervals will be a brief scan.

Validity:

Changes must be entered in program mode.

Other Considerations:

Related Topics:

UDP, Enter PPP Mode, Enter SLIP Mode, AT Command Mode

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Set Hardware Configuration

Command to set the hardware release version number, i.e. Rev 3.2, Rev 3.3, Rev SM-1 etc.. The

hardware configuration setting is set at the factory and should not normally be set by the user. The

hardware configuration version can only be set in Diagnostic mode.

ATI3 Query Hardware configuration

AT#NH=number Set Hardware configuration

AT#NH? Query Hardware configuration

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Profile Configuration Commands

Description:

Upon power-on/reset, the NRM issues a HELLO (verbose) or a 9 (terse) result code and proceeds to

CDPD mode.

These commands affect settings that are stored in the modems Non-Volatile Memory (NVM). These

commands are used by service personnel when the unit is installed and as required thereafter to update

service access information. Note that some configuration changes will not be permanently saved until

they have been written to Non-Volatile Memory (NVM) with the AT&W command.

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Program Mode

Description:

Program mode permits the user to change S register parameters that affect the modems operation.

Program mode was created as a means of protecting the configuration of the modem from spurious or

unwanted attempts to change them. The addition of the password protects the equipment from

unauthorized access and modification. While in program mode, the modem is disconnected from the

network. Data cannot be sent or received over the wireless link.

Format:

AT\APROG,NRM6812 Enter program mode

AT&W Save changes and exit program mode

ATZ Exit without saving changes

The password field is case sensitive. The modem will distinguish upper and lower case letters to be

different. In the above example, NRM6812 is the default password. NRM must be entered as capital

letters otherwise the password will not be accepted. Passwords should be more than six characters

however the software will accept any number of characters up to 8.

Validity:

The user can enter program mode while in AT Command mode.

Other Considerations:

Besides being used as the password for entry into Program mode, the password is also used as a qualifier

for the escape sequence used to exit data modes. Care should be used when changing passwords.

Related Topics:

Changing Password, Saving Settings, Soft Reset, S Registers,

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Local Echo

Description:

The Set Local Echo command permits the user to select whether the modem should echo the characters

sent to it back to the host. For some applications, local echo is not required as the host does not need to

confirm what has been sent to the modem. For terminal operation, local echo can be used to verify what

has been sent to the modem and aids in sending commands, since each keystroke is displayed on the

terminal.

Format:

ATE0 Disable Local Echo

ATE1 Enable Local echo

Validity:

Changes to the local echo setting are valid during program or AT command modes. Changes made while

not in program mode will be lost upon power down. Changes made and saved while in program mode will

be retained by the modem.

Other Considerations:

For a wide variety of applications, local echo is not required or desired. When using local echo with a

terminal, it is wise to keep in mind that the application being used may require local echo to be off rather

than on. Always ensure that the echo setting is set in the proper mode for the application when re-

installing a modem.

Related Topics:

Saving Settings, AT Command Mode

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Response Format

Description:

The Set Response Format command is used to define what manner the modem returns when commands

are sent to it. Responses can be defined to be either plain text messages or a single numeric digit.

Numeric control is better suited for machine applications while plain text is better for interpretation by

humans.

Terse

mode Verbose mode

(Plain Text) Description of Response

0 OK Command accepted.

1 CONNECT Connection established.

2 RING Network origination indication.

3 NO CARRIER Connection terminated, not established or command aborted.

4 ERROR Invalid command parameter/state (e.g. DTR must be active before ATD can be

accepted.)

5 NO SOCKETS No free TCP sockets within S7 seconds.

6 NO DIALTONE CDPD link not established.

7 BUSY Refused by destination or network, OR: Operation in progress.

8 NO ANSWER No response received from the destination within S7 seconds.

9 HELLO Issued at power on/reset.

Format:

ATV0 To enable the response to be in the numeric format

ATV1 To enable the response to be in plain text

Validity:

Changes to the Response Format setting are valid during program or AT command modes. Changes

made while not in program mode will be lost upon power down. Changes made and saved while in

program mode will be retained by the modem.

Other Considerations:

Some machine applications use the plain text response as it saves reformatting the information for

presentation to a human operator.

Related Topics:

Saving Settings, AT Command Mode

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Programmable I/O

Description:

Commands used to configure the General Purpose I/O lines for predefined functions. Any of these signals

can be associated with any of the GPIO pins on the interface. However, due to the nature of the power up

state of these pins, recommendations on which signals should be associated with which pins will be

provided.

Format:

All changes to the state of the GPIO signal associations will only be allowed while in Program Mode of the

modem. Also, any changes will only take place only upon device power up.

To enter program mode: at\aprog,<password>

ATIO1? To query the current setting of GPIO1

ATIO1=<code> To set the operating function of GPIO1

ATIO2? To query the current setting of GPIO2

ATIO2=<code> To set the operating function of GPIO2

ATIO3? To query the current setting of GPIO3

ATIO3=<code> To set the operating function of GPIO3

ATIO4? To query the current setting of GPIO4

ATIO4=<code> To set the operating function of GPIO4

ATIO5? To query the current setting of GPIO5

ATIO5=<code> To set the operating function of GPIO5

ATIO6? To query the current setting of GPIO6

ATIO6=<code> To set the operating function of GPIO6

To save the profile: at&w

Default Configuration:

OEM: Pin Type Signal

GPIO1 O RS232 Control

GPIO2 O Service Indication

GPIO3 O Ready

GPIO4 O RF All

GPIO5 I Power Boost

GPIO6 O Ring

Minstrel III: Pin Type Signal

GPIO1 O RS232 Control

GPIO2 O Service Indication

GPIO3 O Hot Sync / Alert

GPIO4 O Message Waiting Indication

GPIO5 I Power Down

GPIO6 O Low Battery Indication

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Selection Codes

Code Type Pins Description

0 -- --- Defaults by modem type

1OGPIO1-6 High

2 O GPIO1-6 Low

3 O GPIO1-6 Ready (binary, ON once registered, OFF if modem has to

hunt for service).

4 O GPIO1-6 Service (current flashing scheme for service detection).

5 O GPIO1-6 Alert (provides positive pulse if PUSH message queued).

6 O GPIO1,2,4,6 Ring (negative logic, OFF if RING, ON once data mode

started).

7OGPIO1-6 RF (Tx).

8OGPIO1-6 RF (Rx).

9 O GPIO1-6 RF (Rx or Tx).

10 O GPIO1-6 Low Battery Indication. Will be asserted when first threshold

in NVM is reached.

11 O GPIO1-6 Message Waiting (like Alert, ON if PUSH message queued,

OFF when last PUSH released).

12 O GPIO1,2,4,6 RS 232 Power Down (asserted when the unit is in sleep

mode, de-asserted during normal op).

100 I GPIO1-6 Power Down indication (when asserted, modem will de-

101 I GPIO1-6 Power Boost indication (when asserted, modem will enter

Power Boost mode ).

Validity:

If the register is set to zero, the modem will use the default setting.

Setting can be changed at any time by the host when in Program Mode but will not be saved unless a

AT&W is performed.

Other Considerations:

For additional information on the electrical characteristics of the pins and their placement on the

connector, please consult the Expedite Wireless IP Hardware Interface Specification.

Related Topics:

Host Interface/Power Connector, Program Mode, Low Battery Warnings, Power Boost feature,

Push Technology

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Soft Reset

Description:

The soft reset command is used to return the modem to the initial conditions upon power up. The Soft

Reset will return S Registers to their stored values, restart the channel scan process, clear all data buffers

including any pending data that is still contained within the modem. The modem will shut down any

existing stack in an orderly manner. A soft reset will de-register a modem from the CDPD network if

necessary.

In PROG mode, this command may be used to exit without saving any NVM changes.

Format:

ATZ To perform a modem soft reset

Validity:

Valid for AT Command and Program Modes.

Other Considerations:

Upon issuing a Soft Reset, the modem will disconnect from the CDPD Network and restart the channel

scan procedure. This results in a temporary lapse in the modem’s ability to send or receive data. Before

initiating a data mode session (PPP, SLIP, UDP or TCP) immediately following a soft reset, it is

recommended that the application verify that the modem is registered on the network.

Related Topics:

S Registers, Enter Program Mode, Saving Settings

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Side Preference

Description:

This command allows the user to specify the CDPD Service Side preference. Since there are two sides

within a CDPD service area this command makes it possible to specify one side over the other or simply

force the unit to either side only. Check with your carrier to determine on which cellular side CDPD

service is provided.

Format:

AT\N? To determine current setting use

AT\N1 To set the unit to A side only

AT\N2 To set the unit to B side only

AT\N3 To set the unit to A side Preferred

AT\N4 To set the unit to B side Preferred

Validity:

The AT\N command can be used at any time while the unit is in Command or Program Mode. The unit

does not need to be in Program Mode for this command to take effect. The setting is stored in NVM each

time the setting is changed.

Other Considerations:

Along with the side preference, it is often recommended that a user specify a Service Provider Identifier

(SPI) or Service Provider Network Identifier (SPNI) to direct the modem to search for a preferred carrier

as that carrier may not be on one side throughout the country.

Related Topics:

Setting SPI, SPNI, WASI; Setting Carrier Preference;

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Password

Description:

The set password command is used to change the alphanumeric password string used to secure the entry

to program mode and also as a qualifier for the activation of the escape sequence. The password can be

set to a string of alpha, the letters a to z in both upper and lower case and the numeric digits 0 to 9.

Spaces are not allowed. Upper and lower case alpha characters are distinguished as different characters.

A null string, one containing no alpha or numeric characters is considered valid. It is recommended that

the password string be 6 to 8 characters in length for optimal security.

Format:

AT\P=oldpwd,newpwd,newpwd To change the password the command

Example AT\P=NRM6812,NEW6812,NEW6812

In the above example, NRM6822 is the old password (set at the factory) while NEW6812 is the new

password being entered. Two copies are required as can be seen by the entry of NEW6812,NEW6812.

To enter a null string as a password the command would take the form of

AT\P=NRM6812,,

There is no way to read back and determine the password once it has been set.

Validity:

The change password command is valid for Program mode.

Other Considerations:

Care should always be exercised when changing the password. While not all applications warrant altering

the password, the need for additional security may be partly satisfied by configuring the password.

For users that make use of the Escape sequence, setting the password to the null string configures the

modem to operate in a manner similar to the Hayes modems. The NRM6812 escape sequence does not

support the idle time requirement. It simply scans the data stream for the escape characters followed by

the password. When the password is a null string, the modem operates similar to a Hayes Modem.

Related Topics:

Escape Sequence, Program Mode, Data Modes

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Escape Sequence

Description:

The Data Mode Escape sequence is used to discontinue use of the internal UDP or TCP stack. The

escape sequence does not cause any deviation to SLIP or PPP operation and would not normally be used

in this manner. Unless the modem has been set to use the TCP Suspend feature, once the escape

sequence is encountered by the modem it will terminate the current session, tear down the stack and

enter AT Command mode.

If the modem has been programmed to use the TCP Suspend feature, the modem will not tear down the

stack but will temporarily suspend the TCP session and enter AT Command mode. This would permit the

host time to access other parameters to alter the manner of communications.

The escape sequence consists of the string “+++” followed by the program mode password (normally

NRM6812). There is no requirement for a guard time or other special pauses before, after or in between

escape sequence characters. The string must be an exact match, matching both letter/number and case.

The password can be set to a string of alpha, the letters a to z in both upper and lower case and the

numeric digits 0 to 9. Spaces are not allowed. Upper and lower case alpha characters are distinguished

as different characters. A null string, one containing no alpha or numeric characters is considered valid. It

is recommended that the password string be 6 to 8 characters in length for optimal security.

Format:

+++<password> Escape Sequence

Example +++NRM6812 Default Password

Hayes Compatible +++ Password is set to null string

Validity:

The escape sequence can be used to exit the internal TCP or UDP data modes.

Other Considerations:

For users that make use of the Escape sequence, setting the password to the null string configures the

modem to operate in a manner similar to the Hayes modems. The NRM6812 escape sequence does not

support the idle time requirement. It simply scans the data stream for the escape characters followed by

the password. When the password is a null string, the modem operates similar to a Hayes Modem.

Related Topics:

Set Password, Program Mode, Data Modes

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Hardware Flow Control

Description:

The set flow control command is used to configure the modem to either respond to the hardware flow

control signal Request To Send (RTS) and generate Clear To Send (CTS) or ignore them and pass data

without regard to the RTS input. When flow control is turned off, CTS is set active.

Format:

AT\Q? Query current flow control setting

AT\Q0 Set flow control off (Default)

AT\Q2 Set Flow control on (Hardware)

Validity:

Flow control can be set while in AT Command Mode or Program Mode. Changes made to the flow control

setting take effect immediately. There is no need to enter program mode and save the settings.

Other Considerations:

Due to the asynchronous nature of sending and receiving data over a wireless channel, it is recommended

that flow control be set on so that the host and modem can eliminate data overflow problems. Should the

application require only sporadic data reception and transmission of short data packets, the use of

hardware flow control is considered optional.

Related Topics:

Data Mode, Program Mode, Hardware Interface.

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Disconnect (Hang-up)

Description:

The Disconnect or Hang-up Command is used to end a TCP or UDP session and possibly power the

modem off. When the ATH0-3 command is used, it ends the data mode session and puts the modem into

AT Command mode. When the ATH4 command is used, the data mode session is terminated, the

modem will perform a de-registration from the network and initiate a shutdown.

Format:

ATH0 Terminate session & return to AT Command mode

ATH1 Terminate session & return to AT Command mode

ATH2 Terminate session & return to AT Command mode

ATH3 Terminate session, de-register, and return to AT

Command mode

ATH4 Terminate session, de-register and shutdown

Validity:

Valid for TCP and UDP data modes.

Other Considerations:

Related Topics:

Data Mode, Program Mode, Hardware Interface.

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Restore Factory Defaults

Description:

The restore factory default command sets the following S registers to their default factory setting. The

settings are stored in RAM only and will not be saved unless a Save Settings command is issued before

power down or a soft reset.

Format:

AT&F Restore factory defaults

Validity:

This command is valid only in Program mode.

Other Considerations:

Not all registers are altered by the Restore factory default command. For a complete listing of S register

settings see the S Register summary.

Related Topics:

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Line Speed and Format

Description:

This command allows the user to specify the data bit rate or “line speed” and format of the host serial port

for all subsequent communications. Some applications have the need for operating at a different line

speed, other than 9600, because of existing or established wire-line software. The line speed change will

not take effect until the registers have been saved and the modem reset.

Format:

ATS23? To determine the current line setting

AT&L? To determine the current line setting

ATS23=<S>,<D><N> To change the serial port settings

AT&L<S>,<D><N> To change the serial port settings

Where: <S> = Baud rate in bits/second: [1200 | 2400 | 4800 | 9600 | 19200]

<D> = Number of data bits [7 | 8]

= Parity [O | E | N]

<N> = Number of stop bits [1 | 2]

Examples (all have 8 bits, no parity, 1 stop bit)

For 19200 enter AT&L19200,8N1

For 9600 enter AT&L9600,8N1

For 4800 enter AT&L4800,8N1

For 2400 enter AT&L2400,8N1

For 1200 enter AT&L1200,8N1

Default Setting 9600,8N1

Note:

When AT&L is entered the modem will interpret this as AT&L1200,7O1 (7 bits, odd parity, 1 stop)

Validity:

This command is valid only in Program Mode. Serial port change will not occur until settings are saved

and a soft reset occurs.

Other Considerations:

The NRM does not support the auto-baud detection function. Characters received with parity errors are

ignored by the NRM with no indication to the Host.

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Related Topics:

Software Reset

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View Active Profile

Description:

This command displays the current active configuration state of most NRM data registers.

Format:

AT&V View active profile

Validity:

Valid in AT Command and Program modes.

Other Considerations:

Related Topics:

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Save Current Profile

Description:

This command is used to save any changes made to register settings or configuration parameters. All

values are stored in the modems Non-Volatile Memory (NVM). Upon power-up or after a soft reset, the

configuration parameters are retrieved from NVM and used to determine the modem’s operation. A Soft

reset is generated automatically, once the values are stored in NVM. By performing the soft reset, the

modem will temporarily drop its connection to the network. The modem will then scan for channels and

reconnect to the network as soon as it has completed the registration process.

Format:

AT&W Save changes

Validity:

The Save Current Profile is valid only in Program mode.

Other Considerations:

Once executed, the profile parameters are saved and the modem exits Program Mode by doing a soft

reset. After Reset, the modem will first enter AT Command mode and may then carry on and enter a

default mode if configured accordingly.

Related Topics:

Soft Reset, Default Mode,

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Destination IP Address/Port

Description:

This command is used to store the default IP address for the remote host. When the modem is directed

to establish a session using TCP, or send UDP packets, without specifying an IP address, the IP address

specified by register S53 is used at the destination IP. The addition of a preceding “T” or “P” is used to

define a default mode of operation when one is not supplied with the ATD command. The ‘port value’ is

the TCP/UDP port number used to identify the application in the remote host to be used for the

connection-oriented service.

Format:

ATS53? Query destination IP Addr /Port

ATS53=T1.2.3.4/1 Set the destination IP Addr/Port

Where: <mode> = Optional access mode for remote host

T = TCP (default).

P = UDP

<address> = IP address: xxx.xxx.xxx.xxx

<port> = TCP/UDP port number [1 - 65535]

Example ATS53=166.140.73.2/2100

IP = 166.140.73.2

Port = 2100

Validity:

Valid in either AT Command or Program modes. The value specified is stored immediately in NVM.

Other Considerations:

If set to a non- zero string, this port number is attached to all transmitted packets in UDP-Data mode.

Related Topics:

TCP mode, UDP mode, Default mode,

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Debug Mode

Description:

This command sets the NRM into debug mode, sending debug information out the serial port. The debug

information is generated by the “Radio Resource Manager” (RRM) portion of the modem’s internal

software. This piece of code oversees the operation of the modem, monitoring the physical connection,

channel management and data transport. Debug information is generated only while the modem is in AT

Command mode. Once the modem enters a data mode, the debug information stream is suspended

since this would interfere with the data transfer operation.

An alternative to the debug mode is to use the MSCI protocol and monitor the modem’s operation

interactively. The MSCI protocol requires a PPP or SLIP link to be used and then sends special UDP

messages directly to the modem. The modem responds to the UDP messages returning the requested

modem operation data.

Format:

AT#X=1 Enter debug mode

AT#X=0 Exit debug mode

Validity:

Valid in AT Command mode only.

Other Considerations:

Debug mode cannot be entered in Program mode since the modem is disconnected from the network and

the RRM is not running.

Related Topics:

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Auto Answer (TCP Listen)

Description:

a remote server or another modem. The modem can remain in AT Command mode while the modem is

waiting for a session request to be received.

The session activation process begins when the host asserts DTR (if DTR operation is selected) to inform

the modem that it can accept the session request.

The modem will issue a “RING” string to the host to indicate that a session has been initiated. The

modem may also generate a CMOS and/or a RS-232 RING signal coincident with sending the RING string

if programmed to do so. The IP address port number, stored in register S53, is used as a qualifier for the

session request.

Format:

ATS0? Auto Answer Query

ATS0=1 Set Auto Answer mode ON

ATS0=0 Set Auto Answer mode OFF

Validity:

Auto answer mode can be set in either AT Command or Program mode. Setting changes to auto answer

are saved immediately.

Other Considerations:

Related Topics:

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Connection Establishment Time-out

Description:

When initiating a session request as a remote client, attempting to talk to a server, a time-out limit for

establishing the connection can be specified by setting register S7 to the appropriate value. When a TCP

session request is sent out by the modem, the server being called will respond with either an acceptance

or busy message. If the server does so before the time-out limit is reached, the modem will respond with

the acceptance string “CONNECT” or the declining string “BUSY. The server will usually return a “BUSY”

message when it is overloaded and cannot accept further sessions. If the server being called does not

respond in the time allowed, the modem will respond with an ERROR message to indicate that it could not

establish a session.

Format:

ATS7? Connection Timeout value

General Command format ATS7=<time-out>

Where: <time-out> = time-out value in seconds [0 - 255]

Default 60 seconds

Example command ATS7=45 programs a value of 45 seconds for the time-out

value.

Validity:

This command is valid only in Program mode. The value must be saved with the AT&W command.

Other Considerations:

Related Topics:

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Data Forwarding Idle Time-out

Description:

When using the internal stack either UDP or TCP, the data being sent to the modem is automatically

encapsulated in an IP packet using the preset protocol. The packet size may vary depending upon the

rate at which the data characters are received. If the data is received in a very sporadic manner, the

modem will assemble and send a packet after an idle period has elapsed, no data is received in this

interval. This keeps the data moving, retaining some time relevance instead of waiting for a specific

number or a full buffer. The modem will also send a packet if a return character is encountered in the

data stream.

The timer value is programmable from 0.1 to 25.5 seconds in 1/10th of a second resolution.

Format:

ATS50? Data Forwarding Idle Time-out

General command format ATS50=<time-out value>

Where: <time-out value> = Time-out value in 1/10th seconds [0 -

255]

Example command ATS50=15 the time out value is set to 1.5 seconds

Default factory setting is 0.5 seconds

Validity:

Other Considerations:

For most applications, data is sent in bursts, with each burst of data having relevance within the

application. To define the length of each packet, it is recommended to send the data in bursts followed by

a return. Packet length will vary as both UDP and TCP include overhead information in each packet.

Typically TCP will include a 40 byte header while UDP uses less than 20 bytes for header information.

UDP is generally used to reduce data transmission costs but requires the application to handle lost

packets and retries.

Related Topics:

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Data Forwarding Idle Character

Description:

When using the internal stack either UDP or TCP, the data being sent to the modem is automatically

encapsulated in an IP packet using the preset protocol. The packet size may vary depending upon the

rate at which the data characters are received. If the data is received in a very sporadic manner, the

modem will assemble and send a packet after a specific character is encountered in the data stream. A

normal idle character configuration would be a CR or NL character. This register will configure which idle

character to forward information on.

Format:

ATS51? Query Data Forwarding Idle Character

ATS51=0 Disabled Data Forwarding Idle Character

ASS51=aa Data Forwarding Idle Character values of 1-255

Validity:

Other Considerations:

Related Topics:

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UDP Half Open Mode

Description:

Once the modem is configured to operate in the half-open mode, it can accept AT commands from the

keyboard, it can also receive UDP packets through the RF channels for the duration specified by the user

without performing and ATD command.

The modem can accept UDP packets from any destination. But once it receives a packet, it locks onto

that destination and automatically goes into the regular UDP mode. It stays in that mode until either the

DTR is dropped, the escape sequence is sent or the Half-Open timer expires. The timer restarts every

time a packet is received or sent. For example, if the timer is set to 30, the Monitor will stay in the UDP

mode until 30 seconds after the last UDP packet is received or sent. Once the modem exits active UDP,

it returns to the Half-Open mode.

If the destination address is set to a nonzero value, everything will work the same as the above except that

it will only accept UDP packets from that specific destination and ignore the rest.

Format:

ATS82=0 regular mode

ATS82=1 not used (reserved)

ATS82=2 Half-Open mode enabled

Query: ATS82?

Command: ATS82=<mode>

Where <mode> 0 = Regular mode

1 = Not used (reserved)

2 = Half-Open mode

Validity:

This command can only be issued in command mode.

Other Considerations:

automatic UDP stack to remain active for that amount of time (measured in seconds).

ATS83? Query UDP Open Timeout

ATS83=60 Set UDP Open Timeout

sets the timer to 60 seconds.

Related Topics:

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Status Reporting

Description:

The CDPD Status Reporting feature provides a status code to be automatically issued each time the

modems connection status changes. The status message is encoded using a string of five letters. Each

letter position indicates the current status of a particular condition or phase in the modems operation.

A or I RSSI, received signal

strength intensity,

A = >-100 dBm

I = <-100 dBm

. “A” indicates a signal strength in excess of –100 dBm while an “I”

indicates a signal strength below –100 dBm. It is generally found that

modem operation is most reliable when the signal strength is above –

100 dBm.

B or J Current forward

channel error rate

B = < 3%

J = > 3%

The second letter is used to indicate the current error rate on the

forward channel (modem receiver). The letter “B” indicates an error rate

lower than 3%, which is considered acceptable in most applications

since it can be easily corrected within the Reed Solomon coding

scheme. The letter “J” is used to indicate an error rate above 3%.

Errors above 3% can cause delays in data reception and may require

retransmission of data between the modem and the base station.

C or K Found CDPD Service

C = Service found

K = No Service yet

The third letter is used to indicate that the modem has found a cellular

channel with CDPD service. The modem indicates the existence of the

available channel using a “C”. Until a channel is found the modem will

issue a “K” in the third letter position. Should the modem not establish a

connection it will hunt for another channel, putting out a “K” until a new

channel is found.

D or L Registration indicator

D = Registered

L = Not Registered

The fourth letter is the registration indicator. A “D” indicates that the

modem has successfully acquired a channel and registered with the

network. Data modes can then be used. An “L” in this position indicates

that the modem has not yet registered.

E or M Scan Mode

E = Set on Channel

M = Scanning

The fifth and final letter is used to indicate when the modem is scanning

and when the modem is fixed on a channel. An “E” indicates that the

modem is fixed on a channel while an “M” indicates the modem is

searching for channels. As defined within the CDPD specification the

modem will periodically scan other channels trying to find a stronger

signal or one that is not as heavily used.

Format:

ATS103? To determine the current setting

ATS103=1 To enable status reporting

ATS103=0 To disable status reporting

Validity:

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The status reporting can be enabled or disabled in either AT Command or Program modes. Changes

made in AT Command mode and not saved with the AT&W command in Program mode will not be

retained after power down.

Other Considerations:

Status reporting, if enabled, will continue to operate in PPP and SLIP modes but will be suspended in TCP

and UDP modes.

Related Topics:

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Local IP Address/Port

Description:

Since the modem connects directly to the Internet, it needs to have an IP address to define where data

destined for it can be sent. The two methods for defining IP addresses are static and dynamic. Dynamic

IP addresses are assigned to the modem each time the modem connects to the network. Dynamic IP

addressing poses several disadvantages with messaging services. These difficulties are overcome with

Static IP addressing which is used by the Expedite Wireless IP Modem. Register S110 is reserved for

specifying the IP address for the NRM. The optional ‘port extension’ is the TCP/UDP port number used to

further identify the Host application for the connection-oriented service.5

The IP address must be specified before the modem can register with the network. Please contact your

network provider to receive your IP address. This number is assigned to the modem and must remain

unique; you cannot load the same IP address into more than one modem and have them work. The IP

address cannot be ported or transferred to another modem without alerting your issuing carrier of the

change and the associated Electronic Identifier (EID) numbers of the modems.

Once registered on the Network, the EID and IP must remain in the same modem until the Network is told

to “Trust enable” the modem or “Reset Authentication Parameters” for the modem. During initial

registration of the modem, first time registration, the typical process has the Network accepting the

modem’s EID without checking it and henceforth using that value along with the IP and authentication

keys. This will remain in effect until the Network administrator is instructed to change the IP, EID or reset

the credentials.

Format:

ATS110? IP Address and Port

ATS110=<Address>/<port> To set the IP address

Where: <address> = IP address: xxx.xxx.xxx.xxx

<port> = TCP/UDP port number [1 - 65535]

Example command ATS110=207.107.0.35/2014

IP address is 207.107.0.35

Port number is 2014

This port number is used for “listening” in UDP-Data mode.

Validity:

The IP address can only be changed in Program mode.

Other Considerations:

An IP address consists of 4 numbers, 0 to 255, separated by dots (periods). For IP addresses that

contain zero as one of the numbers, you must enter the zero as part of the IP address as shown in the

example above. An IP address must have four numbers to be valid. Numbers must be limited to 0 to 255

in value. Check with your carrier before making any changes to your IP address setting.

5 This address/port combination is used when the NRM opens the TCP port for listening.

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Related Topics:

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Service ID Preference

Description:

In addition to being able to set the side preference, and specifying the cellular channel side used by the

modem, the user can also specify the preferred carrier that the connection should be made with. Parts of

the information broadcast by the network may include three pieces of information used to identify the

carrier. These identifiers are the Service Provider Identifier (SPI) the Service Provider Network Identifier

(SPNI) and the Wide Area Service Identifier (WASI).

All of these parameters do not need to be sent by the carrier. Each carrier configures their network to use

some or all of these to identify themselves in the various regions of the country where they operate. Some

settings are specific to each region while others are fixed for the entire country. Please contact your

carrier before setting these values.

The Service ID Preference settings work in conjunction with register S116. Unless register S116 is set

properly, the values of register 111 may not have the desired effect.

Format:

ATS111? Query Service ID Preferences

ATS111=<SPI>/<SPNI>/<WASI> Set Service ID Preferences

Acceptable range of values 0 to 65535

Don’t care value setting 0

Example ATS111=0/1206/12300

SPI = Don’t care

SPNI = 1206

WASI = 12300

Validity:

Other Considerations:

For version 1.0 networks (in the process of being phased out) the Service Provider Identifier should be set

to 0 if service provider ID preferences are used.

Related Topics:

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Channel Scan Mode

Description:

The Expedite Wireless IP Modem modems can be programmed to scan for available CDPD channels in

three different manners. Each manner has different operating characteristics and is targeted for specific

applications.

Channel scan mode 0 has the NRM performing an initial scan of all cellular channels associated with the

selected side preference (see AT\N). Service is initially obtained on the CDPD channel with the highest

RSSI. This mode was the first mode developed and was the default mode until mode 2 was developed.

New issue modems default to mode 2 operation.

Channel scan mode 1 has the NRM using only those cellular channels defined in the channel scan list,

regardless of which side they are on. Service is initially obtained on the CDPD channel with the highest

RSSI. This is useful in restricting the modem to obtaining service on only a selection of channels. Once

service is obtained, automatic handoffs may occur sending the modem to a channel not present in the

channel list. If the modem looses the channel, it will only re-scan those channels present in the channel

list.

Channel scan mode 2 has the NRM using the channel list as a “Hot List” scanning those channels first

before scanning outside the list. If service cannot be found on a channel contained in the channel list the

modem will perform a wide scan in an effort to located a suitable channel. If a channel is found which is

not present in the list, it is appended to the list for future use. The modem automatically updates and

maintains the channel list.

The addition of mode 2 operation also expanded the channel list from 16 to 32 entries. The use of the “Hot

List”, offers the advantage of faster connection times since there is a good chance that the channel list will

contain an active channel. Because the modem maintains this list itself, there is no need for the operator

to initialize the modem channel list, the modem will do this itself. When the modem has filled the 32

location list the software will overwrite the oldest entry in the list and continue rewriting old values with new

ones.

Format:

ATS112? To determine the current channel scan mode

ATS112=0 Any channel

ATS112=1 Hot List Only

ATS112=2 Hybrid

Validity:

The channel scan mode can only be altered in Program mode.

Other Considerations:

To optimize performance for mobile applications which use many channels and may roam from city to city,

it may be advantageous to clear the channel scan list when entering a new area. This would eliminate

channels that are not active in one city from affecting the operation of the modem. Doing this will result in

a longer time for primary initialization of the modem as it refills the channel list.

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Related Topics:

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Channel List

Description:

may use to search for CDPD service, depending on the setting of S112. Up to 32 channel numbers may

be entered. If no channel numbers are entered, the NRM will scan the entire CDPD channel set

associated with the side preference.

Format:

ATS113? Channel List query

ATS113=<chan1>,<chan2>,etc. Set channel list

Where: <chan1-32> = All valid CDPD channels [1-799, 991-1023]

To zero the channel list ATS113=

No value is entered

Validity:

The channel scan list can only be altered in Program mode.

Other Considerations:

A channel number of zero is not valid.

Related Topics:

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Service ID Preference

Description:

Format:

ATS116? Query Service ID preference

ATS116=0 To only use S111 service ID

ATS116=1 To prefer S111 service ID

ATS116=2 To not use S111 service ID

ATS116=3 To use any service ID

Default setting 3, use any service

Validity:

This command is valid in Program mode only.

Other Considerations:

Contact your carrier before altering this register value.

Related Topics:

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CDPD Operating Version

Description:

The CDPD specification has gone through two revisions; the first established version 1.0 networks using

dedicated channels. The second version introduced channel hopping and maintained dedicated channels.

Format:

ATS117? CDPD Operating Version

ATS117=10 To set it for Version 1.0

ATS117=11 To set it for Version 1.1

Validity:

This command is valid in Program mode only.

Other Considerations:

Version 1.0 systems are quickly being replaced with version 1.1 systems. Please check with your local

carrier before altering this value.

Related Topics:

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Wireline Compatibility

Description:

In order to accommodate certain host computer systems and their expected responses from the Expedite

Wireless IP Modem, a register is provided which enables the trailing line feed character to be stripped off.

The default setting for the modem is to send the line feed, which is contrary to what some wire-line

modems do. Standard modems operate in the same manner as the NRM. When set to suppress the line

feed character, the modem will send no leading line feed on terse responses and only one response for an

ATD command entry.

Format:

ATS210? Query Wireline Compatibility setting

ATS210=0 To enable the line feed character

ATS210=1 To suppress the line feed character

Validity:

This command is valid in Program mode only.

Other Considerations:

Related Topics:

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Set DTR Control

Description:

For applications or situations where hardware control of the modem is not possible, DTR control can be

over-ridden and the host can avoid the necessity of adding extra control lines. Negating DTR control

poses a problem for exiting a data mode as the normal manner is to de-assert DTR to exit. To exit a data

mode while DTR control is off, the escape sequence can be used.

Format:

ATS211? Query DTR control setting

ATS211=0 To set DTR control ON

ATS211=1 To set DTR control OFF

ATS211=2 Always assert DSR

ATS211=4 Dropping DTR gracefully powers off modem

ATS211=8 DSR Control asserted after registration

0: Default behavior (not 4)

1: Ignore DTR

2: Always assert DSR

4: Asserting DTR does nothing. Dropping DTR gracefully powers off modem.

8: Delay assertion of DSR (when entering data modes) until modem has registered.

Validity:

This command is valid in Program mode only.

Other Considerations:

As stated above, when DTR control is over-ridden, the only way to exit from a data mode is with the

escape sequence. When using TCP auto answer, once a session tear down command is received from

the remote host, the modem will revert to AT Command mode. This transition from data mode to AT

Command mode was initiated remotely, not locally.

Related Topics:

DTR Mode Setting, DSR Mode control

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DTR Mode Setting

Description:

The DTR control can be used to power off the modem in situations where it is desired. This setting is

similar to that of setting register S211 to 4. That is, when DTR is de-asserted, the modem will terminate

any current data mode session, perform a system de-registration and power itself off. This setting can

also configure the unit to ignore DTR, or identical to setting S211 to 1.

Format:

AT&D? Queries DTR mode setting

AT&D0 ignore DTR transitions ( S211 = 1 )

AT&D1 normal operation (default)

AT&D2 de-asserted DTR powers modem off ( S211 = 4 )

Validity:

Other Considerations:

Related Topics:

DTR Control

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DSR Control Setting

Description:

This setting provides more complete control of the DSR configuration. The DTR mode and control settings

provide inferred control of the DSR pin, but this control register allows more specific control of the DSR

configuration.

Format:

AT&S? To query the current DSR control setting

AT&S 0 No control of DSR. It is asserted all of the time

AT&S1 Control of DSR is enabled after modem registration.

AT&S2 Normal operation of DSR. Asserted when data mode.

Validity:

This register is available only in AT Command mode.

Other Considerations:

This register may perform corresponding configuration of the S211 register to reflect any changes

here. As an example, if the current S211 is 2 and this register is set to 1, the S211 will be returned to a

value of 8.

Related Topics:

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TCP Timer

Description:

When using TCP, a session is initiated by one party calling and the other party accepting or declining the

session request. Once a session is established, the two parties listen only to one another (unless multiple

sessions are permitted). After a session is completed and both parties want to disengage, a session tear

down message is sent from one to the other. Both parties tear down the stack and are then available to

set up another session with someone else. In the event that a tear down message is not received by a

modem, an idle timer is available which will tear down the session after a predetermined interval of

inactivity by either party. The values setting for this timer is specified in the TCP Timer register, TCPT.

Format:

ATTCPT? Query TCP Timer setting

ATTCPT=value [ 0 to 255 minutes] To set the timer value (minutes)

ATTCPT=0 To disable the timer

Validity:

Other Considerations:

A setting of 0 indicates the timer is not used. The minimum setting is 1 minute. It should be noted that

when using a sleep mode modem, care should be taken in the selection of an appropriate value, as sleep

intervals may create a longer interval of inactivity.

Related Topics:

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Identity Registers

Description:

The identity registers are used to identify the modem to the host. These read only registers present the

following information:

The modems Electronic Identifier Number (EID)

The Software Version, creation date and time

The copyright header

The modem manufacturer

The model and hardware revision number

Format:

ATI0 To determine the EID

ATI1 To determine sw version & copyright information

ATI2 To determine the manufacturer

ATI3 To determine the hardware version

Validity:

This command is valid in AT Command and Program modes.

Other Considerations:

Related Topics:

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Query Network Connection Status

Description:

The command to determine the current network connection status is used to determine is it is acceptable

for the host to go into a data mode and reliably exchange data over the CDPD network. The status

message returned is encoded using a string of five letters. Each letter position indicates the current status

of a particular condition or phase in the modems operation.

A or I RSSI, received signal

strength intensity,

A = >-100 dBm

I = <-100 dBm

. “A” indicates a signal strength in excess of –100 dBm while an “I”

indicates a signal strength below –100 dBm. It is generally found that

modem operation is most reliable when the signal strength is above –

100 dBm.

B or J Current forward

channel error rate

B = < 3%

J = > 3%

The second letter is used to indicate the current error rate on the

forward channel (modem receiver). The letter “B” indicates an error rate

lower than 3%, which is considered acceptable in most applications

since it can be easily corrected within the Reed Solomon coding

scheme. The letter “J” is used to indicate an error rate above 3%.

Errors above 3% can cause delays in data reception and may require

retransmission of data between the modem and the base station.

C or K Found CDPD Service

C = Service found

K = No Service yet

The third letter is used to indicate that the modem has found a cellular

channel with CDPD service. The modem indicates the existence of the

available channel using a “C”. Until a channel is found the modem will

issue a “K” in the third letter position. Should the modem not establish a

connection it will hunt for another channel, putting out a “K” until a new

channel is found.

D or L Registration indicator

D = Registered

L = Not Registered

The fourth letter is the registration indicator. A “D” indicates that the

modem has successfully acquired a channel and registered with the

network. Data modes can then be used. An “L” in this position indicates

that the modem has not yet registered.

E or M Scan Mode

E = Set on Channel

M = Scanning

The fifth and final letter is used to indicate when the modem is scanning

and when the modem is fixed on a channel. An “E” indicates that the

modem is fixed on a channel while an “M” indicates the modem is

searching for channels. As defined within the CDPD specification the

modem will periodically scan other channels trying to find a stronger

signal or one that is not as heavily used.

Format:

ATS57? To determine current network status

Validity:

This command is valid in AT Command mode only.

Other Considerations:

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Because the modem is disconnected from the network in Program mode, this command will return an

ERROR code if used in program mode.

Related Topics:

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Registration Process

Background

Registration involves 4 message exchanges, all of which have to be successful:

M-ES MD-IS

TEI REQ ->

<- TEI ASSIGN (MDLP TEI assignment)

SABME ->

<- UA (MDLP link reset)

<- IKE

EKE -> (SNDCP key exchange)

ESH ->

<- ISC (MNRP registration)

This is the system's response to a registration request, and is basically an accept or deny (refer to Table

507-6 in the CDPD specification for all possible responses). The modem will simply pass the information

("insufficient credentials" in this case) along to the user.

Different MD-IS manufacturers may treat the same condition differently, and may return different

responses in their ISC's. The CDPD specification provides a substantial amount of guidance but some

aspects are left to the discretion of the implementor.

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Last network registration error code

Description:

Should the modem fail to register within a sizable window of opportunity, typical times vary from 3 to 5

seconds for a “Hot List” match to 30 seconds for a “Wide Scan” match, it may have encountered a

network registration error. To determine if this is the case, the network registration error register can be

read to see if there is a non-zero value. If the value is zero, then the modem has yet to attempt to register

on a valid channel as it has yet to find a channel or form a link to the network.

For non-zero values consult the table below.

Response Meaning

1 No particular reason given

2 MD-IS not capable of handling the M-ES at this time

3 NEI is not authorized to use this subnetwork

4 M-ES gave insufficient authentication credentials

5 M-ES gave unsupported authentication credentials

6 NEI has exceeded usage limitations

7 Service denied on this subnetwork; service may be obtained on alternate Service

Provider network

8-255 Reserved

For further assistance if a non-zero value is present, please contact your carrier and provide them with this

information.

Format:

ATS200? To determine last registration error

Validity:

Valid for AT Command mode only.

Other Considerations:

Most Network Registration problems are due to a mismatch of the authentication credentials. These

values are stored in both the modem and the Network MDIS Information database. If these values get out

of sync, registration may not be possible. Problems can be experienced when trying to register on an

alternate carrier through an “interop” agreement link. Because the modems use the internet for

communications, information may be slow in arriving at the intended destination or may be lost along the

way. Interop links introduce additional delays in delivering registration information that can result in

temporary failure to register. This situation should typically not persist for more than 2 minutes.

Related Topics:

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Authentication Parameter

Description:

The Authentication Parameters can be set to zero using the AUTH command. This command is only

used if the network equipment requires the modem to start service using a zero key value. If this

command is entered after the modem has successfully registered on the network, the authentication

parameters will not match the value stored on the network and the modem will not be able to re-register

with the network.

Format:

ATAUTH To reset authentication keys to zero

Validity:

This command id valid for AT Command mode only.

Other Considerations:

Related Topics:

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Query Current RSSI Value

Description:

To determine the current Receive Signal Strength Intensity, RSSI, value for the current channel being

scanned, register S202 can be read. The RSSI value is presented as the relative signal strength above

the modem noise floor. The absolute value is determined by adding the relative value from register S202

to the noise floor value of –115 dBm.

It is important to remember that the modem can be scanning while this inquiry is made, thus the value

read back may not be valid for the channel that is later retrieved from the current channel register.

Format:

ATS202? To determine the current RSSI value

Validity:

This command id valid for AT Command mode only.

Other Considerations:

Related Topics:

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Query Current Block Error Rate (BLER)

Description:

The modem maintains statistics on its performance and operation. One of the parameters measured and

maintained is the block error rate. This measurement is derived by examining the Reed Solomon

algorithm, that part of the modem’s software that can detect and correct errors in the data stream. Data

errors that cannot be corrected result in a re-transmission of the bad segment while errors that can be

corrected do not result in data re-transmissions. The modem measures the errors and, based upon an

error rate threshold, then uses this measurement to decide when to change channels. The block error

rate can rise to 3% before the effect becomes noticeable by the user. The block error rate is updated

approximately every second or two when the modem is connected to the network.

Format:

ATS203? To determine the current Block Error Rate

The response will be in the form of a percentage [ 0 to 100%]

Validity:

This command is valid for AT Command mode. For use in data modes, the MSCI protocol is preferred.

Other Considerations:

Related Topics:

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Current RF Channel in use

Description:

To determine the current channel that the modem is currently locked to, the contents of register S204 can

be read. This value represents the cellular channel number and does not, by itself, indicate that this is a

CDPD channel, a voice channel or even if there is any RF signal being received. Because the modem

periodically scans for better channels trying to improve service, the channel number returned may not be a

valid CDPD channel. The modem will eventually scan all channels on the desired side or sides, even

those which are not CDPD enabled. This results in the channel value being returned by the modem may

have been one which was being scanned when the command was accepted by the modem. This means

that the user must take care in interpreting the channel number as being a CDPD channel as it may not

be.

Format:

ATS204? To determine the current channel

Validity:

This command is valid in AT Command mode only.

Other Considerations:

Frequency and Channel Assignments

Mobile Transmit Base Transmit Channel Use Band

824.04 – 825.00 869.04 - 870.00 991 - 1023 Voice A

825.03 – 834.36 870.03 - 879.36 1 - 312 Voice A

834.39 – 834.99 879.39 - 879.99 313 - 334 Control A

835.02 – 835.62 880.02 - 880.62 335 - 356 Control B

835.65 – 844.98 880.65 - 889.98 357 - 666 Voice B

845.01 – 846.48 890.01 - 891.48 667 - 716 Voice A

846.51 – 848.97 891.51 - 893.97 717 - 799 Voice B

Related Topics:

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Cell Site ID in Use

Description:

The CDPD Network is composed of a multitude of cellular towers transmitting their signals over a portion

of the total coverage area. By reusing frequencies, a greater density of coverage can be maintained and

more calls supported. To make each tower identifiable to remote terminals (modems), an identifying ID

number is sent in the forward data stream. This number, [0 to 65535] is useful in reporting problems to

the cellular carrier when the cellular signal is in question.

Format:

ATS205? To determine the current Cellular ID

Validity:

This command is valid in AT Command mode only.

Other Considerations:

Related Topics:

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Area Color Code in Use

Description:

The CDPD Network is composed of a multitude of cellular towers transmitting their signals over a portion

of the total coverage area. By reusing frequencies, a greater density of coverage can be maintained and

more calls supported. To distinguish the same channel frequency used on two towers, carriers assign

each one a different color code. The color code is a number from zero to seven. This information assists

the network in routing the information being sent to the modem through the right cell site tower.

Format:

ATS206? To determine the current color code

Validity:

Other Considerations:

Related Topics:

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Power Level Query

Description:

The Power Level query will return the current transmit power level being used by the modem on the

current CDPD system. This power level is a product of the proposed power level and received signal

strength values at the modem.

Format:

ATS207? To determine the current power level

Validity:

Other Considerations:

Related Topics:

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Symbol Error Rate Query

Description:

A percentage rate of symbol errors encountered by the modem on the Forward channel is provided to

assist in identifying sub-optimal signal conditions. The value returned is a percentage representing the

number of symbol errors per 100.

Format:

ATS208? To query the current Symbol Error Rate.

Validity:

Other Considerations:

Related Topics:

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Power Product

Description:

The Power Product is a CDPD system parameter that ultimately determines the power level used by the

modem for transmissions. This value is transmitted by the CDPD system and can reported in this register.

Format:

ATS209? To query the current power product

Validity:

This register is read-only.

Other Considerations:

Related Topics:

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Authentication Failures Query

Description:

The number of authentication failures is available here in a register. The concept is to track the number of

times that the authentication credentials were invalid since the last known point as a means of identifying

any unusual behavior of the modem firmware, or failures in the EE device. There are set and query

commands that can be used to “reset” the count back to zero at the factory if problems have been

encountered.

Format:

ATAF? Query the authentication failures.

ATAF=0 To reset the register to zeros.

Validity:

Other Considerations:

Related Topics:

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Dial (Connection Setup)

Description:

In wire-line modems a connection s made when the modem is instructed to dial a telephone number for

the desired computer service. This dial command ATD provides the user with the means of using either

tone dialing, ATDT, or pulse dialing, ATDP. For wireless Internet modems using CDPD technology, the

ATD command is used to initiate a session with a remote Internet server using either TCP/IP or UDP.

Instead of a phone number, an IP address is used instead. It is here that the use of the Internet makes

CDPD easy to use as there are no area codes, no country codes, no need to access an outside line. All

IP addresses currently use a fixed length series of four numbers separated by dots.

The Dial Connection Setup command causes the NRM to establish a connection with the host at the

specified IP address/port. For any fields that are left blank, values are taken from those stored in the

default destination register. The NRM will not process this command if the DTR line is not asserted (i.e.

an ERROR response is issued). It is recommended that the host application make sure the modem is

connected to the network before issuing a Dial command.

Format:

ATDT<IPaddress>/<port#> To initiate a TCP Session

ATDP<IPaddress>/<port#> To initiate a UDP Connection

ATDN<Ipaddress> To initiate a Telnet Session. Port 23 is assumed.

ATD To use the Default Register

IPaddress format XXX.XXX.XXX.XXX

where XXX is a number [0 to 255]

port# format XXXXX

where XXXXX is a number [0 to 65535]

Examples

TCP Connect ATDT166.1.109.3 (no port given, 0 assumed)

IP = 166.1.109.3

Port = 0

UDP Connect ATDP166.1.109.3/55000 (Port number specified)

IP = 166.1.109.3

Port = 55000

Default Connection ADT (S53=P166.1.109.3/55000)

Same effect as above

Validity:

This command is valid for AT Command mode only.

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Other Considerations:

Related Topics:

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ADC Monitoring

Description:

It is anticipated that many of the users of the Expedite Wireless IP Modem will wish to do so in a mobile

environment, and thus one where the supply voltage may not be constant. To that end, a power condition

control system has been provided.

A block diagram of the battery/power condition system is shown below. It contains:

a. A method of voltage measurement on the modem. This is represented by the AN_IN input, which is

routed on the board to the input of ADC channel 1.

b. A method of reading the voltage measurement from the modem. This is effectively the reading of the

ADC channel 1.

c. A method of identifying when the measurement crosses a threshold. The ability to read the voltage is

matched with the entry in the EE device representing a warning ADC value. If the voltage read from

the ADC is lower than this EE warning value, the warning indication is asserted.

d. A method of specifying the hysteresis associated with the measurements. Once the warning indication

has been asserted, it will only be de-asserted once the ADC measurement is >= Warning +

Threshold.

e. A method of modem shutdown when a critical voltage measurement is reached. If the voltage read

from the ADC is lower than the EE shutdown value, the modem will initiate a de-registration and shut

off.

f. A method of enabling/disabling this monitoring feature. All of these features can be enabled/disabled

with an entry in the EE.

Given that the monitoring functions have been enabled, the signals associated with these functions can be

selectively enabled on any of the GPIO pins on the interface connector. Obviously, if the associated

signals with this feature are not provided on the interface, external devices will not see any of the warnings

and must simply identify when the modem has shutdown.

Signal Name : Low Battery Indication

Asserted when the first threshold is reached. After assertion, it will be de-asserted only if

the voltage measurement is >= low battery threshold + hysteresis count

AN_IN

GPIOn

ADC

CPU

Low Battery Indication

Power Fail Indication

Tx Power Fail

Warning

Shutdown

Hysteresis

Enable

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Format:

AT#ADM? Queries the current ADC monitoring mode setting

AT#ADM=0 No ADC monitoring

AT#ADM=1 Enable ADC monitoring mode

AT#ADT? Query ADC monitoring thresholds

AT#ADT=x,y Set the thresholds for the ADC monitor.

AT#ADH=x Sets the hysteresis value

AT#ADN=x,y,z Sets the hysteresis count values.

AT#ADC? Queries the current AN_IN reading.

AT#ADV=r Sets a calibration voltage of the ADC.

For the most part, all ADC measurements will be provided in volts. The idea is that once the ADC readings

have been calibrated such that the firmware knows what ADC value represents what actual input voltage,

all other ADC measurements can now be converted to voltage.

The ADV command forces calibration of the ADC to the currently applied voltage to its input and

associates the parameter voltage to this ADC reading. For instance, a 4.10 volt reference voltage could be

applied to the AN_IN pin and then the following command “AT#ADV=4.10” would be sent in program

mode. Upon receipt of this command, the raw ADC reading would be sampled and averaged for 10

readings and the result saved and associated with the voltage of 4.10 volts. All other ADC functions can

now use voltage values based on this calibrated point and a mathematical relationship.

In the case of the thresholds, the values entered will represent the ADC voltage at which the Low Battery

Indication(x) and the modem shutdown(y) will occur, respectively. The hysteresis value entered is a

representation of how much the voltage reading must rise once the Low Battery Indication has been given

before the Low Battery Indication will be de-asserted. The counts indicate the number of measurements

(with a 1 second period) over the three transition points that must be observed before a valid transition is

identified . This ensures that minor transgressions are not identified as failures until they have been

qualified through the use of the counts. The three counts represent the additional qualification of

transitions from good->low (x), low->off (y), and low->good (z) in the command “AT#AND=x,y,z”.

There will be cases where the AN_IN measurement would be useful to customers/users as an extra ADC

measurement block, but where the power condition monitoring use of the readings are not desired. In this

case, the configuration would be to disable the ADC monitoring mode ( AT#ADM=0 ) but still use the

AT#ADC? queries to identify the voltage at the ADC directly. The host software is then free to use this

reading however they wish.

Example:

As an example of how this may be used, we will assume the following conditions:

• the supply voltage on the board is externally connected to the AN_IN pin on the connector

• an LED is connected to GPIO 2, which we want to use for Low Voltage indications.

• we wish for the Low Voltage indication to trigger at 3.5V, from a regulated 4.OV regulator.

• we wish to initiate a shutdown of the modem if the modem identifies a voltage of 3.3V.

• we wish to de-assert any Low Voltage indication if the voltage rises to 3.6V.

• we wish for 5 counts of each voltage to be observed before we accept the transition.

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Configuration:

In order to use these features, we must perform some configuration of the system to reflect our desires.

The order of events to configure the system is as follows:

AT\APROG,NRM6812 *enter program mode

AT#ADV=4.0 *assumes that the voltage input currently is 4.0 volts

AT#ADV=3.5,3.3 * configures the warning and shutdown thresholds

AT#ADH=0.10 * configures the hysteresis to be 3.6V-3.5V or 0.10V

AT#ADN=5,5,5 * configures the hysteresis counts to be 5 readings

AT#ADM=1 * enables the low voltage monitor

ATIO2=10 * enables the Low Battery Indication signal on GPIO2.

AT&W * saves all settings.

This completes all configuration functions associated with the desired power monitoring system that we

defined. The system will now perform the following monitoring:

If voltage is >= 3.5V, no indications

If voltage is 3.3V <= v <= 3.5 for 5 counts, low battery indication is given and LED lights

If voltage rises above 3.6V for 5 counts then, low battery indication is removed and LED turns off

If voltage falls below 3.3V, unit powers off.

Validity:

This command is valid for AT Command mode only.

Once the monitoring functions have been enabled, the shutdown functions will operate. However, the

signals associated with the warnings will only appear on the interface if the Programmable GPIO pins

have been configured to report the associated signals.

Other Considerations:

The voltage measurement is also available through MSCI commands.

Related Topics:

General Purpose IO, Program Mode, Save Profile command

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Ping Command

Description:

The Ping command causes the modem to transmit a single ICMP packet of the specified size to the

ICMP/PING entity of the specified address. The data sent is a simple random pattern that the targeted

destination will return in the same format as it was sent. If the packet is returned, then the path from the

modem to the destination address location is intact. If the message is not returned then the path may not

be intact or the destination address may not be able to respond. The Ping command is a very useful tool

in trouble shooting problems and confirming the modems operation.

Upon issuing the Ping command the modem will send the ICMP Ping message to the destination address.

The modem will wait for a return message. If the destination address returns the Ping message before 20

seconds has elapsed, an OK result code is emitted. If the Ping message is not returned in less than 20

seconds, an ERROR result code is emitted. Additional PING commands must not be issued if a PING

command is already in progress, you must wait for either the OK or the ERROR response.

The ping command can be used to send messages up to 128 bytes in length by adding a forward slash

and a number, 1 to 128, afterwards. If no forward slash is included the Ping message will be 32 bytes in

length.

Format:

ATPING<XXX.XXX.XXX.XXX>/<Length> To send a ICMP Ping message

IPaddress format XXX.XXX.XXX.XXX

where XXX is a number [0 to 255]

Length value range [1 to 128]

Validity:

Other Considerations:

In earlier versions of the modem software a BUSY result code was emitted upon transmitting the ICMP

Ping message. There is currently no trace route function within the modem. This function is resident in

Windows 95 and can be run using PPP or SLIP and the external stack.

Related Topics:

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Power Boost

Description:

This feature provides support for an external 3watt booster.

Format:

ATAC? To query the configuration

ATAC=0 To turn off 3 watt booster support

ATAC=1 Configuration for 3 watt booster compatible antenna

Validity:

Other Considerations:

There is also an input signal that can be configured to provide this selection as well.

Related Topics:

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Message Waiting

Description:

This command turns on the Message Waiting signal if it exists.

Format:

ATMW? To query the state of the signal

ATMW=1 To turn on the Message Waiting signal

ATMW=0 To turn off the Message Waiting signal

Validity:

Obviously, this feature is only valid if there is an output pin associated with this signal.

Other Considerations:

Related Topics:

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Internal MRU Setting

Description:

This feature defines the maximum negotiated MRU size during a PPP session. In many host systems, the

host stack will configure a default MRU size from its own defaults, but this may not be the optimum size

for the CDPD network. Further, some implementations of host TCP/IP stack do not allow the modification

of this default by the users. Therefore, in order to properly support these stacks in a wireless CDPD

environment, the ability to dictate the negotiated MRU size to an optimum value regardless of host

configuration will be supported in this register.

Format:

AT#MRU? To query the current setting

AT#MRU=xxx Set the MRU value

By default, the MRU recommended by the CDPD system is approximately 512 bytes.

To set the default MRU size to 512, you would enter the following:

AT\APROG,NRM6812 - enter PROGRAM mode of operation

AT#MRU=512 - set the value to 512

AT&W - to save it

Validity:

This value is configurable in PROGRAM mode only.

Other Considerations:

Related Topics:

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TCP Suspension Enable

Description:

This allows any TCP session to be suspended.

Format:

AT#TCPX? Query TCP suspend enable

AT#TCPX=0 Disable TCP suspend feature

AT#TCPX=1 Enable TCP suspend feature

Validity:

Other Considerations:

Related Topics:

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Call Progress Result Mode

Description:

Format:

ATX? Query the call progress selection

ATX=xx Set the call progress selection

Validity:

Other Considerations:

Related Topics:

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Answer

Description:

This feature represents of the normal ATA answer command. In this system, the ATA will be sent by the

host to release any pending push messages, which would have asserted the Ring Indication line of the

modem interface.

Format:

ATA To answer a Ring Indication

Validity:

Other Considerations:

Related Topics:

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Telnet Echo

Description:

A command to assist in Telnet terminal emulation. This command and the associated S register

determine how characters are echoed, either locally, remotely or with no echo.

Format:

ATS60? Queries echo mode

ATS60=0 No echo

ATS60=1 Local echo (default)

ATS60=2 Remote echo

Validity:

Other Considerations:

Related Topics:

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Modem Identification

Description:

This feature allows another AT command to query the Modem ID or EID value.

Format:

ATI Queries modem EID

ATI0 Queries modem EID

Validity:

Other Considerations:

Related Topics:

The ATI0 command can be used for the same function.

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Friends Mode

Description:

In “Friends” mode, the modem can be configured to reject all messages received that do not originate

from a “friendly” IP address. Up to 10 “friendly” IP addresses can be entered. Once a series of “friendly” IP

addresses or ranges have been entered, enabling “Friends” mode will block reception of data except from

IP addresses in the list. If a message arrives that is not from a “friend” and “Friends” mode has been

enabled, the message will be silently discarded.

Format:

ATFM=0 “Friends” mode disabled

ATFM=1 “Friends” mode enabled

ATFM? Queries the “Friends” mode setting

ATFn=a.b.c.d Sets entry n in “Friends” list to be IP address a.b.c.d

ATF? Queries all 10 entries in the “Friends” list.

In the “Friends” list, entries are indexed from 0 so valid entry positions are 0-9.

When defining IP addresses, 255 can be used as a wildcard.

As an example, suppose that you wish to only accept messages from IP 125.125.125.128 and from any IP

in the 210.180.45 subnet. This could be configured with the following commands:

ATF1=125.125.125.128

ATF2=210.180.45.255

ATF?

0=125.125.125.128

1=210.180.45.255

2=0.0.0.0

3=0.0.0.0

4=0.0.0.0

5=0.0.0.0

6=0.0.0.0

7=0.0.0.0

8=0.0.0.0

9=0.0.0.0

ATFM=1

Validity:

This security feature is only available in the TCP and UDP PAD modes, and the AT command mode. This

security feature is NOT available when a PPP or SLIP data mode is used.

The “Friends” mode feature can be configured in both AT mode or Program mode. Modifications to the

“Friends” list are saved immediately, regardless of mode.

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Other Considerations:

Related Topics:

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Stack Check

Description:

This feature allows users to query the number of unused bytes on the stack. This query is useful in

diagnosing stack related problems. It is assumed that this command will not be normally used by users,

but may be useful for Customer Service personnel. The value returned is a decimal representation of the

number of unused bytes on the stack.

Format:

ATSC? Queries the number of bytes unused in the stack.

Validity:

Other Considerations:

Related Topics:

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Quiet Mode

Description:

This feature allows for Quiet mode of AT operation. In this mode, there are no responses sent to the host

for any AT command entered.

Format:

ATQ? Queries the current setting of Quiet Mode

ATQ0 Disables Quiet Mode (normal responses)

ATQ1 Enables Quiet Mode

Validity:

The “Quiet” mode setting can be set in either AT or Program mode. However, if set in AT mode, the

setting is temporary and will be reset at the next power cycle.

Other Considerations:

Related Topics:

Echo and Verbose Mode of AT Responses.

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Registration Mode

Description:

This feature allows control of whether or not the modem will attempt to register upon initialization and to

control when it will attempt registration at other times.

When registration mode is set to automatic, the modem will begin attempting to become registered on the

CDPD network as soon as it is initialized. When registration mode is manual, the modem will wait until

commanded to register before making such attempts. The modem can be commanded to register directly

by executing the ATO command, or by entering one of PPP or SLIP data modes (AT\APPP or AT\ASLIP

respectively). The modem can be commanded to deregister if registered and to cease attempting to

it started to register because it entered the data mode, it will stop trying to register when it leaves that

mode.

Format:

ATREGMD? Queries the current setting of Registration Mode

ATREGMD=0 Sets automatic registration mode

ATREGMD=1 Sets manual registration mode

ATREGST? Queries current registrations status:

0 = not currently attempting to register, 1 = currently

registered, or attempting to register

ATO Begin attempting to register if not already doing so

ATH3 Deregister if registered and cease further attempts to

Validity:

ATREGMD can only be changed in program mode and only has effect at modem initialization time. The

other commands are only effective in AT mode.

Other Considerations:

Related Topics:

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Fixed Parameters

The following behaviors are fixed for the NRM.

BEHAVIOR SETTING Equivalent

AT command

Online Mode Echo Disabled ATF0

Extended Result

Codes Enable all ATX2

Transmit Control Automatic timed AT\T1

Subscriber Identity NRM supports only one NEI. AT\S0

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Unsupported Commands

The following commands (listed in CDPD Part 2014) are not supported by the NRM. If these commands,

or any other AT command not described above, are received, the NRM will return an ERROR response.

ATF Online Mode Echo

AT\F Set Data Forwarding Operation

AT\M Manual Transmit Control

AT\R Network Registration Control6

AT\S Set Subscriber Identity

AT\T Automatic Transmit Control

AT&C DCD mode

Unsupported Functions

The following functions (listed in CDPD Part 2014) are not supported by the NRM. The commands are

supported such that if they are received during operation, an OK response will be returned but they

perform no real functions. These commands are primarily supported to ensure backward compatibility with

previously released AT Command sets of our product.

ATS102 Pending Data Disposition

ATS114 Set Channel Quality Override Mode

ATS115 Set Channel Quality Override Parameters

6 The NRM automatically registers with the CDPD network upon power on/reset.

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Appendix A: AT Command Set Quick Reference

ATS250? Query Wake Up Protocol State 15

ATS250=1 Enable Push Technology 15

ATS250=0 Disable Push Technology 15

ATS251? Query Number of Pending Messages 15

ATS252? Query First Push Message 15

ATS253? Query Type of First Push Message 15

ATS254=1 Discard Current Message 15

AT\ASLIP The command to enter SLIP mode 16

AT\APPP The command to enter PPP Mode 17

AT#ZZ? Sleep status query command 21

AT#ZZ=0 Disable sleep feature 21

AT#ZZ=1 Enable Long cycle sleep 21

AT#ZZ=2 Enable short cycle sleep 21

AT#NSZZ Out-of-service Sleep status query command 22

AT#NSZZ=0 Disable out-of-service sleep feature 22

AT#NSZZ=1 Enable out-of-service sleep feature 22

AT#NSZZTM=p,b,c,n Configure out-of-service sleep feature 22

ATMD0 For AT Command mode at power-up 25

ATMD1 For SLIP Data mode at power-up 25

ATMD2 For PPP Data mode at power-up 25

ATMD3 For UDP Data mode at power-up 25

ATMD83 UDP with no IP address verify on incoming packets 25

ATI3 Query Hardware configuration 26

AT#NH=number Set Hardware configuration 26

AT#NH? Query Hardware configuration 26

AT\APROG,NRM6812 Enter program mode 28

AT&W Save changes and exit program mode 28

ATZ Exit without saving changes 28

ATE0 Disable Local Echo 29

ATE1 Enable Local echo 29

ATV0 To enable the response to be in the numeric format 30

ATV1 To enable the response to be in plain text 30

ATIO1? To query the current setting of GPIO1 31

ATIO1=<code> To set the operating function of GPIO1 31

ATIO2? To query the current setting of GPIO2 31

ATIO2=<code> To set the operating function of GPIO2 31

ATIO3? To query the current setting of GPIO3 31

ATIO3=<code> To set the operating function of GPIO3 31

ATIO4? To query the current setting of GPIO4 31

ATIO4=<code> To set the operating function of GPIO4 31

ATIO5? To query the current setting of GPIO5 31

ATIO5=<code> To set the operating function of GPIO5 31

ATIO6? To query the current setting of GPIO6 31

ATIO6=<code> To set the operating function of GPIO6 31

ATZ To perform a modem soft reset 33

AT\N? To determine current setting use 34

AT\N1 To set the unit to A side only 34

AT\N2 To set the unit to B side only 34

AT\N3 To set the unit to A side Preferred 34

AT\N4 To set the unit to B side Preferred 34

AT\P=oldpwd,newpwd,newpwd To change the password the command 35

+++<password> Escape Sequence 36

AT\Q? Query current flow control setting 37

AT\Q0 Set flow control off (Default) 37

AT\Q2 Set Flow control on (Hardware) 37

ATH0 Terminate session & return to AT Command mode 38

ATH1 Terminate session & return to AT Command mode 38

ATH2 Terminate session & return to AT Command mode 38

ATH3 Terminate session, de-register, and return to AT Command mode 38

ATH4 Terminate session, de-register and shutdown 38

AT&F Restore factory defaults 39

ATS23? To determine the current line setting 40

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AT&L? To determine the current line setting 40

ATS23=<S>,<D><N> To change the serial port settings 40

AT&L<S>,<D><N> To change the serial port settings 40

AT&V View active profile 42

AT&W Save changes 43

ATS53? Query destination IP Addr /Port 44

ATS53=T1.2.3.4/1 Set the destination IP Addr/Port 44

AT#X=1 Enter debug mode 45

AT#X=0 Exit debug mode 45

ATS0? Auto Answer Query 46

ATS0=1 Set Auto Answer mode ON 46

ATS0=0 Set Auto Answer mode OFF 46

ATS7? Connection Timeout value 47

ATS50? Data Forwarding Idle Time-out 48

ATS51? Query Data Forwarding Idle Character 49

ATS51=0 Disabled Data Forwarding Idle Character 49

ASS51=aa Data Forwarding Idle Character values of 1-255 49

ATS82=0 regular mode 50

ATS82=1 not used (reserved) 50

ATS82=2 Half-Open mode enabled 50

ATS83? Query UDP Open Timeout 50

ATS83=60 Set UDP Open Timeout 50

ATS103? To determine the current setting 51

ATS103=1 To enable status reporting 51

ATS103=0 To disable status reporting 51

ATS110? IP Address and Port 53

ATS110=<Address>/<port> To set the IP address 53

ATS111? Query Service ID Preferences 55

ATS111=<SPI>/<SPNI>/<WASI> Set Service ID Preferences 55

ATS112? To determine the current channel scan mode 56

ATS112=0 Any channel 56

ATS112=1 Hot List Only 56

ATS112=2 Hybrid 56

ATS113? Channel List query 58

ATS113=<chan1>,<chan2>,etc. Set channel list 58

ATS116? Query Service ID preference 59

ATS116=0 To only use S111 service ID 59

ATS116=1 To prefer S111 service ID 59

ATS116=2 To not use S111 service ID 59

ATS116=3 To use any service ID 59

ATS117? CDPD Operating Version 60

ATS117=10 To set it for Version 1.0 60

ATS117=11 To set it for Version 1.1 60

ATS210? Query Wireline Compatibility setting 61

ATS210=0 To enable the line feed character 61

ATS210=1 To suppress the line feed character 61

ATS211? Query DTR control setting 62

ATS211=0 To set DTR control ON 62

ATS211=1 To set DTR control OFF 62

ATS211=2 Always assert DSR 62

ATS211=4 Dropping DTR gracefully powers off modem 62

ATS211=8 DSR Control asserted after registration 62

AT&D? Queries DTR mode setting 63

AT&D0 ignore DTR transitions ( S211 = 1 ) 63

AT&D1 normal operation (default) 63

AT&D2 de-asserted DTR powers modem off ( S211 = 4 ) 63

AT&S? To query the current DSR control setting 64

AT&S 0 No control of DSR. It is asserted all of the time 64

AT&S1 Control of DSR is enabled after modem registration. 64

AT&S2 Normal operation of DSR. Asserted when data mode. 64

ATTCPT? Query TCP Timer setting 65

ATTCPT=value [ 0 to 255 minutes] To set the timer value (minutes) 65

ATTCPT=0 To disable the timer 65

ATI0 To determine the EID 66

ATI1 To determine sw version & copyright information 66

ATI2 To determine the manufacturer 66

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ATI3 To determine the hardware version 66

ATS57? To determine current network status 67

ATS200? To determine last registration error 70

ATAUTH To reset authentication keys to zero 71

ATS202? To determine the current RSSI value 72

ATS203? To determine the current Block Error Rate 73

ATS204? To determine the current channel 74

ATS205? To determine the current Cellular ID 75

ATS206? To determine the current color code 76

ATS207? To determine the current power level 77

ATS208? To query the current Symbol Error Rate. 78

ATS209? To query the current power product 79

ATAF? Query the authentication failures. 80

ATAF=0 To reset the register to zeros. 80

ATDT<IPaddress>/<port#> To initiate a TCP Session 81

ATDP<IPaddress>/<port#> To initiate a UDP Connection 81

ATDN<Ipaddress> To initiate a Telnet Session. Port 23 is assumed. 81

ATD To use the Default Register 81

AT#ADM? Queries the current ADC monitoring mode setting 84

AT#ADM=0 No ADC monitoring 84

AT#ADM=1 Enable ADC monitoring mode 84

AT#ADT? Query ADC monitoring thresholds 84

AT#ADT=x,y Set the thresholds for the ADC monitor. 84

AT#ADH=x Sets the hysteresis value 84

AT#ADN=x,y,z Sets the hysteresis count values. 84

AT#ADC? Queries the current AN_IN reading. 84

AT#ADV=r Sets a calibration voltage of the ADC. 84

ATPING<XXX.XXX.XXX.XXX>/<Length> To send a ICMP Ping message 86

ATAC? To query the configuration 87

ATAC=0 To turn off 3 watt booster support 87

ATAC=1 Configuration for 3 watt booster compatible antenna 87

ATMW? To query the state of the signal 88

ATMW=1 To turn on the Message Waiting signal 88

ATMW=0 To turn off the Message Waiting signal 88

AT#MRU? To query the current setting 89

AT#MRU=xxx Set the MRU value 89

AT#TCPX? Query TCP suspend enable 90

AT#TCPX=0 Disable TCP suspend feature 90

AT#TCPX=1 Enable TCP suspend feature 90

ATX? Query the call progress selection 91

ATX=xx Set the call progress selection 91

ATA To answer a Ring Indication 92

ATS60? Queries echo mode 93

ATS60=0 No echo 93

ATS60=1 Local echo (default) 93

ATS60=2 Remote echo 93

ATI Queries modem EID 94

ATI0 Queries modem EID 94

ATFM=0 “Friends” mode disabled 95

ATFM=1 “Friends” mode enabled 95

ATFM? Queries the “Friends” mode setting 95

ATFn=a.b.c.d Sets entry n in “Friends” list to be IP address a.b.c.d 95

ATF? Queries all 10 entries in the “Friends” list. 95

ATSC? Queries the number of bytes unused in the stack. 97

ATQ? Queries the current setting of Quiet Mode 98

ATQ0 Disables Quiet Mode (normal responses) 98

ATQ1 Enables Quiet Mode 98

ATREGMD? Queries the current setting of Registration Mode 99

ATREGMD=0 Sets automatic registration mode 99

ATREGMD=1 Sets manual registration mode 99

ATREGST? Queries current registrations status: 99

ATO Begin attempting to register if not already doing so 99

ATH3 Deregister if registered and cease further attempts to register. 99

ATF Online Mode Echo 101

AT\F Set Data Forwarding Operation 101

AT\M Manual Transmit Control 101

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AT\R Network Registration Control 101

AT\S Set Subscriber Identity 101

AT\T Automatic Transmit Control 101

AT&C DCD mode 101

ATS102 Pending Data Disposition 101

ATS114 Set Channel Quality Override Mode 101

ATS115 Set Channel Quality Override Parameters 101

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Index of AT Commands

+++.......................................................................... 36

AT#ADC................................................................. 84

AT#ADH................................................................. 84

AT#ADM................................................................ 84

AT#ADN................................................................. 84

AT#ADT................................................................. 84

AT#ADV................................................................. 84

AT#MRU................................................................ 89

AT#NH ................................................................... 26

AT#NSZZ ............................................................... 22

AT#NSZZTM ......................................................... 22

AT#TCPX............................................................... 90

AT#X ...................................................................... 45

AT#ZZ .................................................................... 21

AT&C ................................................................... 100

AT&D ..................................................................... 63

AT&F...................................................................... 39

AT&L...................................................................... 40

AT&S...................................................................... 64

AT&V ..................................................................... 42

AT&W .............................................................. 28, 43

ATA ........................................................................ 92

ATAC...................................................................... 87

ATAF...................................................................... 80

AT\APPP ................................................................ 17

AT\APROG............................................................. 28

AT\ASLIP ............................................................... 16

ATAUTH................................................................ 71

ATD ........................................................................ 81

ATDN ..................................................................... 81

ATDP...................................................................... 81

ATDT...................................................................... 81

ATE......................................................................... 29

AT\F...................................................................... 100

ATF................................................................. 95, 100

ATFM ..................................................................... 95

ATH ........................................................................ 38

ATH3 ...................................................................... 98

ATI.............................................................. 26, 66, 94

ATIO....................................................................... 31

AT\M .................................................................... 100

ATMD..................................................................... 25

ATMW.................................................................... 88

AT\N ....................................................................... 34

ATO ........................................................................ 98

AT\P........................................................................ 35

ATPING.................................................................. 86

AT\Q ....................................................................... 37

ATQ ........................................................................ 97

AT\R ..................................................................... 100

ATREGMD............................................................. 98

ATREGST .............................................................. 98

AT\S...................................................................... 100

ATS0....................................................................... 46

ATS102................................................................. 100

ATS103................................................................... 51

ATS110................................................................... 53

ATS111................................................................... 55

ATS112................................................................... 56

ATS113................................................................... 58

ATS114................................................................. 100

ATS115................................................................. 100

ATS116................................................................... 59

ATS117................................................................... 60

ATS200................................................................... 70

ATS202................................................................... 72

ATS203................................................................... 73

ATS204................................................................... 74

ATS205................................................................... 75

ATS206................................................................... 76

ATS207................................................................... 77

ATS208................................................................... 78

ATS209................................................................... 79

ATS210................................................................... 61

ATS211................................................................... 62

ATS23..................................................................... 40

ATS250................................................................... 15

ATS251................................................................... 15

ATS252................................................................... 15

ATS253................................................................... 15

ATS254................................................................... 15

ATS50..................................................................... 48

ATS51..................................................................... 49

ATS53..................................................................... 44

ATS57..................................................................... 67

ATS60..................................................................... 93

ATS7....................................................................... 47

ATS82..................................................................... 50

ATS83..................................................................... 50

ATSC ...................................................................... 96

AT\T...................................................................... 100

ATTCPT ................................................................. 65

ATV ........................................................................ 30

ATX ........................................................................ 91

ATZ................................................................... 28, 33

Novatel Wireless NRM-3800 CDPD Data Transceiver User Manual Vespa AT Command Set Reference Guide 0 1

Novatel Wireless, Inc. CDPD Data Transceiver Vespa AT Command Set Reference Guide 0 1

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