6i25+7i77 CR16 staying red

Any help will be helpful as I'm completely stuck.

Can you try starting the card from the command line?
You _should_ see something change on the 7i77 when you type"start" as that should start petting the watchdog.

The "show pin" will show if the 7i77 is being detected at all.

Hello andypugh, here's the output:

When "start" command is entered, nothing happen. Leds doesn't change color
Analog side on 7i77 is found ... and that's all
I can turn on/off led CR1 and 2 on 6i25 with "setp hm2_5i25.0.led.CR01 0/1"

Thanks for helping me,
Best regards, Romain.

I think we are back to "sserial device 0.0 (GPIO) is broken" as you concluded some time ago.

I think that a replacement from Mesa might be the answer, though it might actually be cheaper (because of shipping) to buy a new one from eusurplus.

Yes, I think issue is with the communication.
I was hoping to get some schematics to see where RS232 is going after leaving the GPIO.
I will do UART decoding with a picoscope at work to see if I can get information on communication.
Thanks for helping me anyway.