I have serial debugging enabled on COM1 (by pulling the mode pin low) and have the 3.6" Display attached to SPI1 on a Panda I.
When debugging over serial, my display doesn’t show anything. If I switch back to debugging over USB the display works fine.
Is this a known issue/limitation that both COM1 and SPI1 can’t be used together or am I missing something here?
Greetings
How debugging is related to a display connected on SPI bus? 
check your power…step in coder…
Gus, wiring is fine because the display works perfectly when the Panda is connected over USB.
It doesn’t work when I debug over serial. In both cases I’m using an external power supply.
So I can’t see why my wiring should be wrong. In both cases, the display lights up, only when debugging over serial, nothing is drawn on the screen.
Stepping into the code doesn’t reveal anything. It behaves the exact same way as when connected with USB. I’m puzzled.
Very strange! I do not have an explanation
Problem solved.
Was powering the display with 5V instead of 3.3V :-[