Compatibility problems with AVR Dx series microcontrollers.

[Guy1000]

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• Arduino board: AVR128DB28 with DxCore

• Arduino IDE version (found in Arduino -> About Arduino menu): 1.8.13

• List the steps to reproduce the problem below (if possible attach a sketch or
  copy the sketch code in too): **Using SPI1 mapped to portc to use the internal level shifter it doesn't work but works when using spi0 mapped to porta. Everything compiles just fine but when the tft.begin() function is called the microcontroller freezes and becomes unresponsive. Other libraries appear to all operate properly with the spi interface on portc except for this one.

#include <SPI.h>
#include "Adafruit_GFX.h"
#include "Adafruit_ILI9341.h"

#define TFT_DC PIN_PA3
#define TFT_CS PIN_PA7
//#define TFT_RST PIN_PF1 //tied high with resistor
#define TFT_MOSI PIN_PC0
#define TFT_CLK PIN_PC2
#define TFT_MISO PIN_PC1

Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC);

void setup() {
SPI.swap(SPI1_SWAP0); //Swaps to the portc MVIO to use internal level shifters
SPI.begin();
Serial.begin(9600);
Serial.println("STARTED"); //Before function is called the print is successful
tft.begin(); //gets stuck somewhere in here
Serial.println("SUCCESSFUL"); //This print never occurs
}

void loop{ //do nothing

}**