Compute Module • Re: CAM1 not working on a custom board with a CM4

i2c-10 would normally be on GPIOs 44&45.
Prove your wiring by attaching an oscilloscope to those 2 GPIOs, and using "pinctrl set 44,45 op dh", and "pinctrl set 44,45 op dl" to set it high and low respectively.

If proved, then after an "i2cdetect -y 10" I would expect "pinctrl get 44,45" to return SDA and SCL (I've not got a Pi4 booted to give the exact text).

The oscilloscope has some waves on 44 and 45 but changing high to low doesn't change anything.
i2cdetect -y 10 returns all --.

Code:

44: op -- pn | lo // SDA0/GPIO44 = output45: op -- pn | lo // SCL0/GPIO45 = output

and

Code:

44: op -- pn | hi // SDA0/GPIO44 = output45: op -- pn | hi // SCL0/GPIO45 = output

I'd investigate that further. If you can't get it act reliably as an output, then there is something quite wrong.
Do the waves you're seeing actually correspond to I2C traffic, or is it random?

schematic.zip

Statistics: Posted by alessandro.cursoli — Thu Nov 28, 2024 7:55 pm