as we've talked about, I had issues with the LCD not being reset properly (PCB v2.0) and having the LCD show only random pixels. I tried to solve this by soldering a capacitor (100nF) between LCD reset and GND. For fast-rising power supplies, this keeps the reset line low for long enough to properly reset the LCD.
My power bank, however, has a slightly higher rise time for the output voltage, so this didn't work and I had to resort to soldering a bodge wire from one of the GPIO pins (A10) to the LCD reset line (not very fun when the PCBs are already soldered together :wink: ).
Since all pins of the 10 pin header are already used, I suggest we connect the GPIO pin of the STUSB chip to the LCD reset. That way, we can reset the LCD via I²C and not use any additional connections between the PCBs.
Also I'd change all passives on the top PCB to 0402, since it uses the same values as the bottom PCB anyways.
Hi Jan,
as we've talked about, I had issues with the LCD not being reset properly (PCB v2.0) and having the LCD show only random pixels. I tried to solve this by soldering a capacitor (100nF) between LCD reset and GND. For fast-rising power supplies, this keeps the reset line low for long enough to properly reset the LCD. My power bank, however, has a slightly higher rise time for the output voltage, so this didn't work and I had to resort to soldering a bodge wire from one of the GPIO pins (A10) to the LCD reset line (not very fun when the PCBs are already soldered together :wink: ).
Since all pins of the 10 pin header are already used, I suggest we connect the GPIO pin of the STUSB chip to the LCD reset. That way, we can reset the LCD via I²C and not use any additional connections between the PCBs.
Also I'd change all passives on the top PCB to 0402, since it uses the same values as the bottom PCB anyways.
Cheers!