Temperature Humidity Data Logger Commands API 2.4
User Manual: Temperature-Humidity-Data-Logger-Commands-API-2.4
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TEMPERATURE, HUMIDITY & DEW POINT
SENSOR AND LOGGER
API AND COMMAND BOOKLET
Version 2.4
September 2017
Temperature & Humidity Sensor API and Command Guide 2.4
BLUE MAESTRO’S STANDARD LICENSE AND DISCLAIMER
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document belong exclusively to Blue Maestro Limited and no permission to use, copy, modify, and distribute this software or this doc-
umentation is permitted unless with the express prior written authorisation of Blue Maestro Limited. The license to use the software
to which this document relates is granted so long as such software resides in hardware provided by Blue Maestro Limited.
No claims, representations or warranties, whether expressed or implied, including but not limited to warranties of merchantability,
fitness for a particular purpose, of title, or of noninfringement of third party rights, are made by Blue Maestro as to the safety, reliabil-
ity, durability or performance of Blue Maestro’s products. Blue Maestro is not responsible for any liabilities resulting from negligence,
misuse, modification, or alterations to the product by the user. Furthermore, Blue Maestro accepts no liability whatsoever for the
safety, reliability, durability or performance of any of its products. IN NO EVENT, REGARDLESS OF CAUSE, SHALL BLUE MAESTRO BE
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User assumes responsibility for correct operation of the product and any software associated with it. User assumes responsibility for
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ing results obtained from product use.
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Temperature & Humidity Sensor API and Command Guide 2.4
Quick start
1. Download the free iOS or Android App: Tempo Utility App
To get the links to the latest apps, please visit www.bluemaestro.com/support
2. Turn on
The soft touch colour rubber on top of the Device is a button. Depress gently to turn it on. The LED indi-
cator will blink two times to confirm that it is on. Please note it should not be depressed with excessive
force, since this may damage the Device.
3. Turn off
The Device can be turned by depressing the button and holding it down for a period of 5 seconds. It will
blink rapidly to indicate it is turned off.
4. Entering Commands
Type *(star) followed by command name in the command line in the Command Console screen and press
send. The command name and examples are contained further on in this document.
For example type “*bur” into the command console and then send to see streaming temperature,
humidity and dew point up dated every 0.5 seconds.
You will now see temperature, humidity and dew point data shown in the app window.
PLEASE NOTE THIS API DOCUMENT IS FOR FIRMWARE VERSIONS 23 AND ABOVE
Temperature & Humidity Sensor API and Command Guide 2.4
Introduction
This document sets out the specifications, API and the commands of the Blue Maestro Temperature & Hu-
midity Tempo Disc™ Bluetooth® Low Energy Sensor and Data Logger (the “Device”).
The Device uses the nRF52 Bluetooth Low Energy System on Chip from Nordic Semiconductor and a high
quality temperature and humidity sensor from Silicon Instruments. The Device utilises Bluetooth 4.1.
The Device adopts “ad-hoc” pairing where as much information is passed from Device to receiver (smart-
phone, iPad, Bluetooth enabled computer or Gateway) without pairing/bonding being required as possi-
ble. This is done through encoding information within the advertisement packets of the Device. Pairing is
reserved for the passing of commands from receiver to Device or for the extraction of data from the Device
where this cannot be achieved in the advertisement packet (such as logged data, for example).
There has been a great deal of flexibility introduced into the Device to allow settings to be changed. How-
ever care must be taken to ensure that settings are changed correctly. For example if certain undefined/
out of scope variables are input into settings the Device may not perform as desired and, possibly, lock-up
such it may only be able to be recovered by removing and then applying power.
There is a button and LED in the Device. The button is a software button that will cause the Device to con-
sume an ever so small amount of current, even when turned off. To maximise battery life in transportation
and storage it is suggest that the battery is removed/not placed and is only inserted when the Device is to
be deployed.
Temperature & Humidity Sensor API and Command Guide 2.4
BLUETOOTH VERSION 4.1
BLUETOOTH SYSTEM ON
CHIP
Nordic Semiconductor nRF52832
MEMORY 64k RAM, 512k Flash
PROCESSOR ARM Cortex M4 32-bit
BATTERY CR2032, changeable
TEMPERATURE SENSOR
(SILICON LABS SI7020-
AGM)
+/- 0.4 Degrees Celsius (max) with
an operating range of -20 to +75
Degrees Celsius
HUMIDITY SENSOR
(SILICON LABS SI7020-
AGM)
+/- 4% Relative Humidity (max).
Full range 0% - 100% Relative
Humidity
DEW POINT Dew point is calculated from Tem-
perature and Humidity
ANTENNA Johannson Technology
2450AT18D0100 omni-direction-
al chip antenna with matching
tuning circuitry
RANGE up to 75 meters/245 feet line of
sight
HARDWARE FEATURES Polycarbonate exterior with TPE
soft touch button and LED indi-
cator
ENERGY CONSUMPTION OF
NRF52832 RX/TX
nRF52832 Peak TX (0dBm) 5.3 mA;
running from Flash 58 µA for radio
transmissions
ESTIMATED BATTERY LIFE* In excess of 18 months in Logging
Mode (continuous logging and
Bluetooth transmission when
downloading log) and up to 9 - 12
months in Continuous Mode (con-
tinuous logging and Bluetooth
transmission).
SETTINGS FEATURES The following represent some
of the settings that can be
changed using the Command
Console:
Transmit Power, Advertising
Timeout, Name of Device, Rate
of Logging, Password Protect,
Reset Device, Device Informa-
tion, Flight Safe Mode, Thresh-
old Alarms for Temperature,
Humidity or Dew Point (x2)
FREQUENCY OF LOGGING Configurable from every 2
seconds to every 24 hours.
Default is hourly
NUMBER OF LOGS 18,000 data points with 6,000
each of Temperature, Humid-
ity and Dew Point. Log is on
a continuous rotation FIFO
basis and stored in non-volatile
memory
REAL TIME CLOCK Device can be set with time
and date for accurate times-
tamping of logged data.
FLIGHT SAFE MDOE The Device can be put into air-
plane mode such that it logs
data but does not transmit ra-
dio signals. When the button
is depressed, the Device will
advertise for 5 minutes and it
can be taken out of airplane
mode.
IP RATING IP62
REGULATORY EC/FC/RoHS compliant
COUNTRY OF MANUFACTURE United Kingdom
Specifications
The following is the specification for the Tempo Disc unit. For physical dimensions and form see further in
this document.
* Battery life is estimated only can vary depending on device age, use case and
operating temperature. Battery life will be diminished when Disc is operated
continously at temperatures below 0°C.
Temperature & Humidity Sensor API and Command Guide 2.4
Advertisement Data Structure
The following represents the advertisement packet for the sensor. The first 30 bytes is the standard Adver-
tisement payload and the second 30 bytes is the Scan Response payload. They are represented in bytes
with an offset beginning with Blue Maestro’s Bluetooth SIG company identifier 0x33 0x01. This is usually
located at the 16th byte in the full observed advertisement packet. The data structure is little endian.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
0x33 0x01 0x17 0x64 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
0x61 0x09 0x08 0xXX 0xXX 0xXX 0xXX 0xXX 0xXX 0xXX 0xXX 0x00 0x00 0x00 0x00
Blue Maestro’s
SIG identifier
2 bytes
Version No.
uint8_t
Battery lvl in
% of voltage
uint8_t
Stored log count
uint16_t
Current Temp
Int16_t
Current Humidity
Int16_t
Time interval for
logging uint16_t
Current Dew Point
Int16_6
Name of Device
8 bytes
31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
0x33 0x01 0x74 0x53 0x61 0x66 0x65 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
Breach Count
uint8_t
Highest Tempera-
ture Recorded
int16_t
46 47 48 49 50 51 52 53 54 55 56 57
0x61 0x69 0x74 0x53 0x61 0x66 0x65 0x00 0x00 0x00 0x00 0x00
Mode
Int8_t
Name Identifier
0x09
Length of Name
Reserved
4 bytes
Blue Maestro’s
SIG identifier
2 bytes
Highest Humidity
Recorded
int16_t
Lowest Humidity
Recorded
int16_t
Lowest Temperature
Recorded
int16_t
Highest Temper-
ature over last 24
hours - int16_t
Highest Humidity
over last 24 hours -
int16_t
Lowest Temperature
over last 24 hours
int16_t
Lowest Humidity
over last 24 hours -
int16_t
Average Temper-
ature over last 24
hours - int16_t
Average Humidity
over last 24 hours -
int16_t
Global Identifier
uint8_t
Reference Date
uint32_t
Temperature & Humidity Sensor API and Command Guide 2.4
1. UART over BLE Communication
The following are a list of the command line syntax and field requirements to allow settings in the Device
to be changed.
The application includes one service: the Nordic UART Service. The 128-bit vendor-specific UUID of the Nor-
dic UART Service is 6E400001-B5A3-F393-E0A9-E50E24DCCA9E (16-bit offset: 0x0001).
This service exposes two characteristics: one for receiving and one for transmitting (as seen from the nRF5
application).
TX Characteristic (UUID: 6E400002-B5A3-F393-E0A9-E50E24DCCA9E)
If the peer has enabled notifications for the TX Characteristic, the application can send data to the peer as
notifications. The application will transmit all data received over UART as notifications.
RX Characteristic (UUID: 6E400003-B5A3-F393-E0A9-E50E24DCCA9E)
The peer can send data to the device by writing to the RX Characteristic of the service. ATT Write Request
or ATT Write Command can be used. The received data is sent on the UART interface.
All commands and responses are ascii characters unless otherwise stated. The parameter fields of com-
mands and responses are indicated by ‘X’. It is important that the correct number of fields in the parame-
ters are complied with.
If a command is not recognised, the message “Unknown Command” will be transmitted. If a command is
recognised a “Command Recognised” will be transmitted. However even though the command is recog-
nised the parameter may still be incorrect/out of bounds and the Device will not pass any indication.
Where a command is recognised the Device will disconnect and recommence advertising after process-
ing the command. Where a password is entered incorrectly the Device will disconnect and recommence
advertising.
2. Transmission Strength [ *txpX]
This sets the transmission strength of the radio from a choice of three settings of -4dBm, 0dBm and
+4dBm. This can be useful for extending the battery life of the Device but has a negative impact on range.
The default setting is +4dBm.
Parameters:
000 sets to +4dBm
001 sets to 0dBm
003 sets to -4dBm
Temperature & Humidity Sensor API and Command Guide 2.4
3. Logging Interval [*lintX]
This sets the logging interval in seconds. The logging interval represents how frequently the sensor values
are stored in memory. The default is 3600 seconds which represents one hour. When changed, the cur-
rent recorded data will be erased and logging will commence afresh. The minimum is 60 seconds and the
maximum is 43,200 seconds (or 12 hours).
Parameters: x in seconds (default is 3600 = 1 hourly logging interval)
4. Sensor Interval [*sintX]
This sets the sensor interval in seconds. The sensor interval represents how fequently the sensors take read-
ings. The advertisement packets of the device are updated with the latest sensor readings. The defaut is 10
seconds. The minimum is 2 seconds and the maximum is 43,200 seconds (or 12 hours).
Parameters: x in seconds (default is 3600 = 1 hourly logging interval)
5. Password Protect [*pwdXXXX]
This locks the Device from receiving commands or having its log accessed. The Device is not password pro-
tected on shipping. Entering a password will lock the Device until the password is re-entered whereby the
Device will be unlocked until a password is again entered.
Parameters: 4 characters or numbers.
6. Change Name [*namXXXXXXXX]
This changes the Device name from its default. Please note that for some models of smartphone (both iOS
and Android) the name change will not necessarily be recognised until Bluetooth is turned off and back
on in the smartphone settings.
Parameters: 8 characters
7. Advertising Timeout [*atoXXX]
This sets the timeout parameters where advertising will cease after a button push. In all of these cases
advertising will commence in “fast mode” for 180 seconds and then in “slow mode” for a further number of
seconds as defined in this command. The default is 300 seconds or 5 minutes. It is important to note that
without advertising, the Device is not able to be connected to per Bluetooth 4.x protocols.
Parameters: XXX in seconds
Temperature & Humidity Sensor API and Command Guide 2.4
8. Information [*info]
This gives you a list of the current setting including the devices name , version number etc
Parameters: None
9. Telemetrics [*tell]
This gives you a list of the devices telemetrics including sensor frequency, log frequency, number of re-
cords, current temperature and the last 24hours metrics and other key data.
Parameters: None
10. Units of Measure [*unitsf] [*unitsc]
This will convert temperature measurements into either fahrenheit or celsius.
Parameters: None
11. Battery level [*batt]
This gives you the battery level as a percentage of voltage level. As the Device is powered by a CR2032 coin
cell, the voltage begins at 3.00 volts (100%). As the coin cell loses its charge, the voltage will drop. It is advi-
seable to change that the coin cell once the voltage drops to 2.1 volts (70%).
12. Alarm one and two [*alrmUYZXXX]
There are two alarms which track how many times a sensor reading goes below or above a set threshold.
The occurrence of these alarms form part of the advertisement packet and when scanned by a smart-
phone or other receiving device can set off an “alarm”. The Device itself does not alarm.
The alarms can be set for temperature, humidity or dew point. Since there are two, you can set them for
any combination of these.
Parameters: U is the alarm number, either 1 or 2. So *alrm1t>25 sets alarm 1 for temperature over a thresh-
old of 25 Celsius (if this is the units sets for the Device at the time)
Y is the sensor which the threshold applies, either t for temperature, h for humidity or d for dew point. For
example *alrm2h>50 sets alarm 2 for humidity over a threshold of 50% relative humidity.
XXX is the threshold to apply. It is in round numbers, so no decimal points can be specified. For example
*alrm2d<10 sets alarm 2 for dew point below 10 Celsius (if this is the units set for the Device at the time).
Temperature & Humidity Sensor API and Command Guide 2.4
13. Clear alarms [*alrmclr]
This clears the settings for the alarms.
Parameters: None
14. Alarm information [*alrmi]
This provides informations on the alarms, such as settings and how many times the sensor has breached
any thresholds.
Parameters: None
15. Air mode on [*airon]
This sets the air mode on. This causes the Device to log information but not transmit, ideal for transpor-
tation by air. Once this command is entered, the Device will continue to transmit for a further 5 minutes
before ceasing. Depressing the Device’s button will cause the Device to transmit for a further 5 minutes.
Parameters: None
16. Air mode off [*airoff]
This sets the air mode off and the Device will continue to continuously transmit as normal.
Parameters: None
17. Download log in readable form [*loggert] [*loggerh] [*loggerd]
Either of these commands will download the relevant log for temperature, humidity or dew point for
analysis. Note using these commands does not store the data in the smartphone, for this use the specific
download button on the smartphone.
18. Disable Button [*bd]
This command will prevent the button from turning the device on or off. It will still cause the LED to blink
and will cause the device to transmit if it is in airplane mode. This command works on a toggle basis, to
enable the button if it has been disabled pass the command [*bd] again.
19. Calibrate Temperature [*ctXX]
This command will apply an offset to temperature readings to the value of XX. This needs to be integers
(no decimal points) and can be negative. This value needs to conform to the units of measure currently
selected for the device.
Parameters: Integer (can be negative)
Temperature & Humidity Sensor API and Command Guide 2.4
20. Calibrate Humidity [*chXX]
This command will apply an offset to humidity readings to the value of XX. This needs to be integers (no
decimal points) and can be negative.
Parameters: Integer (can be negative)
21. Reference Date & Time [*dXXXXXXXXXX]
This command sets the reference date and time for timestamping the logs. This date and time should
represent when the device was first activated since the device immediately records a log. The reference
date and time can be entered at any time and can be changed subsequently.
The format is a 10 digit number representing Year, Month, Day, Hour, Minute. No seconds are referenced.
For example 11:05pm 23 March 2017 would be represented as 1703232305. To set the date and time to
this the command would be *d1703232305. This value is part of the advertisement packet from the de-
vice.
Parameters: 10 digit number represeting xx[year]xx[month]xx[day]xx[hour]xx[minute].
22. Global Identifier [*idX]
This provides a uint8_t number (0-255) that will be advertised in the Devices advertising packets for iden-
tification, classification or grouping purposes. This can be useful in scanning for Devices where a filter can
be applied based on the global identifier so that only certain devices are picked up in the app.
Parameters: Integer (can be negative)
23. Clear Memory [*clr]
This command will erase the stored logs in the device. However it does not affect the logging interval,
name, global identifier, reference date or the like.
24. Reset to Factory Settings [*rboot]
This command will perform a full reboot of the device and will clear all memory and settings.
Temperature & Humidity Sensor API and Command Guide 2.4
INTENTIONALLY BLANK
Temperature & Humidity Sensor API and Command Guide 2.4
Dimensions and form
The following represents the dimensions and form of the temperature & humidity sensor and logger.
9.5 mm
0.37 inch
33 mm
1.30 inch
