Very weird LCD problem...

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Joined: 31/12/2012
Location: New Zealand
Posts: 9171
Posted: 12:02am 19 Apr 2024      

  Turbo46 said  Is the capacitor the correct value, not reversed, faulty?

Can you run a "hello world" program without the LCD plugged in?


Yes, I have full access to the MM2 chip via the 1455 and USB just fine, but just the LCD that won't co-operate.  Thanks for the idea though.

@ Volhort - This is a 2.2" LCD.  There is no touch controller on it.

MM2 manual, page 18, says that you can use any free pins for D/C and RESET, and CS is permanently connected to ground, so the LCD is always enabled.

VR is old faithful MCP1703A-33.  I've used hundreds of those, and you can suck up to 200mA out of them, but this circuit is way below that, and the LED backlight is connected via it's resistor to 5v, so it is not a load on the VR.

@ phil99 - According to the SPI capture I posted above, the LCD is spitting data back on MISO, but you're right - there is no touch and I am not using the SD socket on the back of the LCD, so I will try your idea of pulling MISO high.  Prepared to try just about anything at this point!  

@ PheonixRising - yes, these forums are wonderful, full of people willing to help.  This place is my 2nd home.  
Edited 2024-04-19 10:10 by Grogster