Overview and steps:
Note: This solution is suitable for Lorawan-Gateway based on RaspberryPi3b+ with chi2-PCB and IMST-iC880a-SPI Board, balena.cloud operated with Draseks´ fork of this repository to use a multi-container configuration. Also see repo before for technical documentation and layout of the PCB) This is a step by step description how to upgrade your ttn lorawan gateway with environmental sensor (Bosch BME280) and digital voltmeter for monitoring input voltage supply.
- BME280 Sensor
- LED Voltage meter 2.5-30VDC
- Optional 1x 4p female connector for I2C Bus
(detailed descripton see bom.txt file with linked suppliers / shops)
- Shutdown power-supply from gateway, remove power supply and antenna-connections
- Open your station-box (or the housing from your system)
- Disconnect any wiring from your device, also the pigtail antenna from the IMST-IC880A board and the LAN-Cable from the RaspberryPi3, power supply from PCB-board
- Remove the complete gateway-unit out of the housing
- Seperate the IMST-IC880A from the PCB --- be careful as this concentrator board is EMD sensitive (and expensive, too) – discharge yourself before touching it or use ESD equipment
- Remove the screws that are fixing the PCB with the RaspberryPi3 to disconnect the two boards
After all preparation were done we can start with the upgrade steps
VOLTMETER With hot-glue you can mount the voltmeter display on to the upper-left corner of the PCB board, just see my sample picture. The wiring can be placed below the PCB by using on oft he prepared holes
Next step is to solder the voltmeter-cables to the power-supply connectors from the PCB from backside ! Ist located next tot he DC barrel connector, marked with „DC input“ Red cable is soldered to the DC input VIN (voltage in) and Black cable is soldered to the DC input GND. You will be able to measure the input-voltage now
Remark: its also possible to use any other Voltage connector for monitoring power supply - maybe you want to read voltage from the output of the step-down converter soldered on the backside of the ch2i-PCB. Just solder it on place you want to read. the GND is always GND anywhere on the PCB.
BME280 Sensor Within the delivery of the sensor is a 6-male connector - we will only use 4-males of this to solder it from the backside to the sensor. So cut it to four pins . Solder it to 3V3, GND, SCL, SDA connectors from the sensor (CSB, SD0 are not used). Next step is to solder the 4p female connector on the PCB board – use one of the I2C Bus connectors from your choice (keep in mind not to cover some screws when the sensor is installed). I used the first position from the I2C bus on the upper middle part from the board. Now you can easyly plug in the sensor module on the I2C bus (watch for the correct pin orientation of 3V3, GND, SCL, SDA).
*Remark: it is also possible to use some dupont-cables (jumper cables male/female) to place the sensor somewhere else inside of your station box if needed. Just plug this extensions between board and sensor if you want to.
After all hardware upgrades are finished you can remount all parts together. Just reverse the description mentioned before
- Place the PCB board on top of the RapsberryPi3 – fix it with the screws as before
- Place the concentrator Board carefully on top of the PCB board
- Remount the Gateway unit inside of the housing
- Reconnect all wiring including antenna (never power the device without antenna !!)
- Power it up again and wait some minutes until it will be online in balena.cloud
After all hardware upgrades are finished we have to do some changes in the balena.cloud to activate the Sensor module BME280.
Therefor login to your balena account with your personal credentials, open the Application where your gateway is located and then open your gateway to reconfigure.
Select the „Device Service Variables“ from the left side-bar. Click on the blue colored button to add new variables. Now you have to configure following variables with values (each time just repeat the step „add new variable“):
Service: Variable Name: Variable.Value:
collectd GW_BME280 true
collectd GW_BME280_ADDR 0x76
collectd GW_BME280_SMBUS 1
Now the configuration is done and the gateway must be restarted to activate changes. Just click on the „restart“ button located in the device summary screen. Some minutes later the gateway should be restarted and active again – in the summary screen you can see that gateway and collectd are marked as „running“
We can check the new sensor - working and measuring environmental data directly from balena.cloud very easy:
Select your application and the device of your balena cloud. From the summary screen start a new terminal session by selecting „collectd“ as target, now start terminal session -- some seconds later you will be connected to your device shell, please type
cd collectd-python-plugins
and ENTER to change the folder ... then type
python bme280.py
and ENTER again to execute the integrated python command
Temperature: 34.63°C
Pressure: 1008.74hPa
Humidity: 19.75%
Congratulations – your sensor is installed properly and reading data !
To finish all the works for this upgrade check all wiring inside of your gateway again and close the box. Install the gateway on its original location and restart power connection.
- ch2i for the PCB (Raspberry PI iC880A and LinkLab Lora Gateway Shield)
- Amedee Bulle for the explanations and his help with sensor integration
- Caspar Armster for support during all the hours of testing