This PMOD connects the Bosch BME280 humidity, pressure and temperature sensor over I2C, using Digilent's PMOD interface type 6A per PMOD specification v1.3.1. The PMOD module can be chained to add additional I2C devices to the bus. The I2C pull-up resistors can be enabled/disabled using DIP switches, and switch 2 toggles the sensors I2C address between 0x76 and 0x77.
This design is registered under the OSHWA Open Source Hardware Self-Certification:
| Pin | Label | Description | Pin | Label | Description |
|---|---|---|---|---|---|
| 1 | - | Not connected | 7 | - | Not connected |
| 2 | - | Not connected | 8 | - | Not connected |
| 3 | SCL | I2C clock | 9 | - | Not connected |
| 4 | SDA | I2C data | 10 | - | Not connected |
| 5 | GND | ground | 11 | GND | ground |
| 6 | 3V3 | 3.3V | 12 | 3V3 | 3.3V |
All pins are passed through from connector J1 to J2, allowing to chain multiple type 6/6A PMODs.
Above shows the BME280 PMOD, connected to a PMOD2RPI interface board. When connected through the PMOD4 connector, the module can be controlled from the Raspberry Pi 4 Linux, running the pi-bme280 control program.
Without any changes, we can run BME280 sample code such as the BMx280_I2C example program from the BMx280MI library provided by Gregor Christandl. The BME280 PMOD module is connected to the PMOD2RPI interface board. On port PMOD1, the module communicates over I2C with the onboard Seeedstudio XIAO Cortex-M0 MCU.
