While tying to migrate the Oberon System 3 to the P4-PC board I have hit the following road blocks (not sure whether this is the right place for this or it was already reported elsewhere):
Rev.C, behaviour reproduced on two separate boards
Not using any of your software or drivers
# 1. USB Serial/JTAG interface drops and re-enumerates continuously
Only started after several flashes and tests
/dev/ttyACM* node then appears and disappears every few seconds for some time with stable phases (~10 minutes) in between
# 2. LT8912B I2C interface strange behaviour when HDMI is connected
The LT8912B is on GPIO7/SDA + GPIO8/SCL
Once a monitor is attached, the LT8912B cannot be (re)configured
If the monitor is attached/detached after a working init, the LT
often loses its HDMI transmitter state and the display stays blue until the LT is re-initialized
What is the hardware revision of the board that you use?