MCU Timeout on connect

[erik.zweigle]

I got to thinking that when I connected the TX/RX pins from SKR PICO to the Pi4B I also attached a GND pin. Looking at the other GPIO pins I saw another GND/5V pair going to the 5V PSU. That PSU shares a GND to the frame, as does the 24V PSU. The Umbilical PCB has +/- to the 24V PSU, but no GND to the Pi4B anymore since I removed the accelerometer hat. So I added a jumper GND connecting Pi4B and Umbilical. Testing again.

 

[erik.zweigle]

Nope. Still mcu timeout. Maybe I'll try removing the HDMI display next. I don't understand how it can print for 20, 40, 90 minutes and then crash. It is never the same amount of time.

 

[erik.zweigle]

Three consecutive successful prints with the HDMI cable and Screen power cable unplugged.

Revisiting the display vendor's wiki it looks like I never added these three lines to my /boot/firmware/config.txt file.

hdmi_group=2
hdmi_mode=87
hdmi_cvt 800 480 60 6 0 0 0

The display draws 400mA during normal operation which does not seem excessive. Continuing to test with the display re-enabled.