Digital Matter I2C Temperature Probe Pinout
Several of our devices have an I2C interface, for connecting sensors. For a list of currently supported sensors, see
Sensors need to be integrated into device firmware before they can be used - but this is typically not a difficult process. Speak to us if you have specific requirements.
We manufacture a 2m long temperature probe - which is a convenient solution for many users. However certain applications will have specific requirements, or perhaps other lengths of probe. In this case, options are:
- Check the list of supported sensors, and use a sensor from this list (will work immediately)
- Source a sensor of choice, and speak to us about integration - will require firmware development (time and cost potentially involved)
- Build a sensor using a TMP75 Chip. This is the same chip used in our 2m probe - so if built in the correct way, custom lengths can be made and work out of box, with no additional integration required.
DM Temp Probe Construction
Our temp probe uses the TMP75 chip. This IC has address pins, and depending on how they are connected, allows various addresses to be set on the probe.
The Falcon, Eagle and SensorNode LoRaWAN will attempt to read from the following addresses when configured to read the 'DM Temp Sensor' in parameters (Falcon & Eagle - Temperature Sensor Setup)
- 146 - 0x92
- 150 - 0x96
- 154 - 0x9A
- 158 - 0x9E
So if we build a probe using a layout that gives it one of these addresses, it will work with our devices.
All of our devices have internal pullups - so they aren't required as part of the probe.
SDA, SCL and GND connected to the relevant connections on the device.
V+, A0 and A1 are connected to VCC
A2 is connected to the green wire on our probe (address select line) - then, when wiring in,
Connecting this wire to GND gives the sensor address 150 (0x96), Temp Probe 1
Connecting it to 3V3 gives the sensor address 158 (0x9E), Temp Probe 2
So up to 2 probes can be used per Falcon/Eagle/SensorNode.