Troubleshooting • Re: [Raspberry Pi5 regression] disabled by hub (EMI?), re-enabling

Port disable events occur due to "port babble" - your UPS is doing something weird when in the process of switching between mains/battery operation. The hub is just more tolerant of whatever it's doing.

Can you do the following on a Pi 5:
1. Unplug all USB devices, connect remotely (UART console or SSH)
2. Run the following commands and check the output matches:

Code:

pi@raspberrypi:~$ sudo busybox devmem 0x1f0020c11c0x8106198Api@raspberrypi:~$ sudo busybox devmem 0x1f0030c11c0x8106198A

3. Run the following commands:

Code:

pi@raspberrypi:~$ sudo busybox devmem 0x1f0020c11c 32 0x8106198bpi@raspberrypi:~$ sudo busybox devmem 0x1f0030c11c 32 0x8106198b

4. Run step 2 again and confirm the two values have a "b" at the end.
5. Connect the UPS and test again.

Statistics: Posted by sblantipodi — Fri Jan 19, 2024 2:52 pm