Having added a Serial Peripheral Interface (SPI) driver, it was tested with a widely available and inexpensive board module that uses the Bosch BMP280 barometric pressure / temperature sensor. Here is a link for a typical example, but there are many alternative sources: Amazon link. You may also need some suitable cabling, such as female-to-female ribbon cable (example here) and a soldering iron to connect the pin header.
If this sensor is connected, the uboot-driver-example test application will use it (see Using the U-Boot Driver Library).
The wiring connections using the MaaXBoard's 40-pin GPIO connector are as follows, accompanied by some reference photographs.
| GPIO Pin | Sensor Pin |
|---|---|
| 17 | VCC |
| 19 | SDA (MOSI) |
| 20 | GND |
| 21 | SDO (MISO) |
| 23 | SCL |
| 24 | CSB (SSO) |
