Appendix A - Mantracourt T24-BSi Technical Manual

Appendix A

Communications Software Overview
Every T24 module has a unique 3 byte ID. This is represented by a 6 character hexadecimal number on its yellow
label.
Acquisition modules also have a Data Tag which is a 2 byte identifier and defaults to the last 2 bytes of the ID (or
the last 4 hexadecimal digits). This Data Tag is used to identify data that is transmitted by the modules in their
operational mode.
Operational Modes
Acquisition devices that supply data have 3 main modes of operation:
Deep sleep
The module is effectively off and draws negligible power from the battery but cannot be communicated with
(Except to wake it).
Default Running
This default mode is how the module operates when power is applied initially. The module transmits its
measured value at a specified interval and can optionally operate in Low Power Mode where the module enters
a temporary deep sleep between transmissions.
Paused
This mode is required when you want to configure or calibrate the module. In this mode the module will
neither return to deep sleep because of its internal SleepDelay nor will it transmit its Data Provider packets.
Operation
The T24 range of acquisition modules are designed so that once configured they would operate autonomously
supplying data to all other modules that require it. There would be minimal interaction with the modules and
would normally only include sending a module to deep sleep or waking a module from deep sleep.
Configuration
When initially setting up a module the T24 Toolkit is used to connect to a module and allows simple configuration
or calibration.
As can be seen from the 3 operational modes listed above this is not always easy as the module may be asleep or
operating in low power mode where communications cannot take place.
The T24 range of modules support PAIRING. This is supported by the T24 Toolkit software and is also available
through the documented radio protocol. It is initiated by power supply removal and replacement so is not suitable
for all occasions such as when the module batteries are not accessible. PAIRING has a distinct advantage in that
forehand information about the target module is not required. PAIRING ensures that the radio channels are
matched between the base station and the module and the ID of the module is not needed to be known
beforehand. Also pairing can be used to make the module enter the PAUSED mode so it can be communicated
with (As in the case of the T24 Toolkit) or just identified and then made to continue with its default run mode.
If pairing is not employed then a manual means of connecting to the module is required. NOTE: this is only
required for configuration as once configured you would just consume the Data Provider packets and possibly
wake/sleep so would not need to pair or otherwise connect to the module.
To configure a device that is in Deep Sleep it is first woken. This can be achieved by using a broadcast wake
where ALL modules on the current radio channel will wake, or wake by ID where just the specific module is
woken. This is preferred otherwise with multiple modules woken and in default running mode there may be lots
of traffic from Data Providers being transmitted which will interfere with the connection/configuration process.
Once the module has been woken it will enter its default running mode and will be transmitting data provider
packets. If the module is not running in low power mode then you could communicate directly using read/write
packets to perform the configuration. It is recommended though to issue a Pause command to stop the module
transmitting data providers and also stopping it going back to sleep after the SleepDelay time has elapsed if that
is enabled.
If the module was operating in low power mode you cannot communicate using the usual read/write commands as
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