Hi,
I am trying to setup a CM3I module to work with one of our products. The board we are trying to design requires the CM3I to drive GPIO114 in order to control an external module.
For initial testing, I seat the CM3I on its IO board, make sure GPIO114 is not exported by default, and attempt to drive GPIO114 to low:
echo 114 > /sys/class/gpio/export
echo out > /sys/class/gpio/gpio114/direction
cat /sys/class/gpio/gpio114/value
# 1
echo 0 > /sys/class/gpio/gpio114/value
cat /sys/class/gpio/gpio114/value
# 1
After exporting the gpio, the module fails to drive the pin as instructed and its value is stuck at 1.
The module is running the cm3i xfce_b4 image found here with no overlays enabled.
| PIN Number | Raspberry Pi CM4 | Radxa CM3I | Function 0 | Function 1 | Function 2 | Function 3 | Function 4 | Function 5 |
|---|---|---|---|---|---|---|---|---|
| 49 | GPIO18 | SPI1_MISO_M1 | GPIO3_C2_d | LCDC_VSYNC | VOP_BT1120_D14 | SPI1_MISO_M1 | UART5_TX_M1 | I2S1_SDO3_M2 |