Hey! I've got a red ili9341. I've got it hooked up to a mega 2560 r3. Pinout is below. When I run the graphicstest example from the Adafruit_ILI9341 library using the software spi constructor and defining all of the pins it works, but very slowly. I want to be able to use the hardware spi constructor, but the display refuses to do anything but display white, and sometimes flicker. When using hwspi graphicstest returns 0x0 for all of its test results and appears to run very quickly even though the screen does nothing. I'm using voltage dividers on the SCK, MOSI, DC, RESET, and CS pins with resistances of 22k and 47k, set up as follows. Mega pin -> 22k -> display -> 47k -> GND
This is what I've tried:
Tying the reset pin to the arduino reset pin and removing TFT_RST from the hwspi constructor, doing the manual reset digitalWrite and delay(10) thing everyone always suggests because of the white screen sleep mode, and switching to ILI9341_AS. Also tried voltage dividing MISO haha.
Display -> Mega 2560 pin
MISO -> 50
LED -> 100ohms -> 5V
MOSI -> VD -> 51
SCK -> VD -> 52
CS -> VD -> 53
DC -> VD -> 49
RESET -> VD -> 48
GND to GND
Vcc to 5V, 100 uF capacitor across the power pins of the display
Ultimately I'm trying to use the Adafruit_imagereader library to load and draw bmps from a microsd card also tied to hwspi. When I tried to just go for that, the white screening began. I figured that since the library made a big deal about both the sd and display needing hwspi I should figure out why that constructor isn't working for me. Let me know if you need my code, but I didn't change anything from the base Adafruit_ILI9341 library and example except to specify the mega hwspi pins and my cs/dc/rst pins.
Update: also tried connecting VCC to 3.3V instead. Still whitescreen. Here's the display: 2.2inch SPI Module ILI9341 SKU:MSP2202 - LCD wiki