GPIO signal excitation

I want to connect Basler aca4112-30uc camera with Nvidia Jetson Xavier NX board. Here is schematic:

If i configure basler as output and jetson as input - it works. Jetson determines booth states 0 and 1 correctly. Here is 0 to 1 transition diagram:

But if i configure basler as input and jetson as output and put line to low (0) - i see abnormal 3V in line:

If i put line high (1), i see “trash” in line:


Please remove the R1 to try again. Before that, you should make sure the pinmux sheet is configured correctly too.

removing R1 is not help. i use command line to control gpio, so i just write out to /sys/class/gpio/gpio268/direction to configure pin as output.

Hi,

Could you share what steps you have done to enable this gpio as output?

Hello Wayne.
Here are steps:
echo 268 > /sys/class/gpio/export
echo out > /sys/class/gpio/gpio268/direction
echo 1 > /sys/class/gpio/gpio268/value

PS: i have tried to use official python lib, but it not work, maybe i could not correctly determine gpio num for it.

Hi,

Could you loop this output pin to other GPIO input pin on 40 pin headers and see if it can observe the signal on NX directly?

I have connect this pin with gpio421 (pin 29) and everything works well. There is no signal excitation on line.

hello dinartal,

besides the GPIO pin configuration in post #7,
may I know had you also refer to Configuring the 40-Pin Expansion Header by using Jetson-IO for configuration.
thanks

No, I haven’t.