Published March 19, 2021 © GPL3+

Tutorial for ILI9341 TFT LCD SD and Arduino MEGA (part 1)

This is a tutorial for the full functionality of ILI9341 connected to a Mega

AdvancedWork in progress18,532

Tutorial for ILI9341 TFT LCD SD and Arduino MEGA (part 1)

Things used in this project

Hardware components

Arduino Mega 2560

ILI9341 2.8 TFT LCD SD

Jumper wires (generic)

Story

At some point, I needed to move from Arduino UNO to MEGA for a project including pictures sounds and some kepads, the problem was there is no library or good explanation about how to connect all the functions of this inexpensive LCD to a MEGA... So here it comes..

I'm using the library <ILI9341_kbv.h> https://github.com/prenticedavid/ILI9341_kbv

but I made some changes to it.

To the file serial_kbv.h

I had to fin the place where defines the pins for each board and change the entire thing for this:

#if 0

#else

#define CD_PIN 48 //DC

#define CS_PIN 53

#define RESET_PIN 49

#define SD_PIN 47 //sd-cs

#define MOSI_PIN 51

#define SCK_PIN 52

#endif

My recommendation is to make a copy of the file with a different name before you do any changes

Code

// EDITED TO WORK ON THE ARDUINO MEGA


#if defined(__AVR_ATmega328P__) && defined(ILI9488_KBV_H_) 
//#define USE_SERIAL_COMPLEX     //optimised C code for Uno, Xmega, ...
#endif
#if defined(__STM32F1__)
#define DMA__STM32F1__         //special feature of MAPLE CORE
#endif
//#define MY_BLUEPILL
// MAPLE core has SPI.write(block, n)
// ST core has only got SPI.transfer(block, n)
// SAMD core might have SPI.transfer(block, n)
// SAM core has got SPI.transfer(block, n)
// so it is probably safest to have a moderate stack buffer and use transfer

//ST core is ok for ILI9341 but not for ST7735X

#define CD_COMMAND PIN_LOW(CD_PORT, CD_PIN)
#define CD_DATA    PIN_HIGH(CD_PORT, CD_PIN)
#define CD_OUTPUT  PIN_OUTPUT(CD_PORT, CD_PIN)
#define CS_ACTIVE  PIN_LOW(CS_PORT, CS_PIN);
#define CS_IDLE    PIN_HIGH(CS_PORT, CS_PIN);
#define CS_OUTPUT  PIN_OUTPUT(CS_PORT, CS_PIN)
#define RESET_ACTIVE  PIN_LOW(RESET_PORT, RESET_PIN)
#define RESET_IDLE    PIN_HIGH(RESET_PORT, RESET_PIN)
#define RESET_OUTPUT  PIN_OUTPUT(RESET_PORT, RESET_PIN)
#define SD_ACTIVE  PIN_LOW(SD_PORT, SD_PIN)
#define SD_IDLE    PIN_HIGH(SD_PORT, SD_PIN)
#define SD_OUTPUT  PIN_OUTPUT(SD_PORT, SD_PIN)
 // bit-bang macros for SDIO
#define SCK_LO     PIN_LOW(SPI_PORT, SCK_PIN)
#define SCK_HI     PIN_HIGH(SPI_PORT, SCK_PIN)
#define SCK_OUT    PIN_OUTPUT(SPI_PORT, SCK_PIN)
#define MOSI_LO    PIN_LOW(SPI_PORT, MOSI_PIN)
#define MOSI_HI    PIN_HIGH(SPI_PORT, MOSI_PIN)
#define MOSI_OUT   PIN_OUTPUT(SPI_PORT, MOSI_PIN)
#define MOSI_IN    PIN_INPUT(SPI_PORT, MOSI_PIN)
#define LED_LO     PIN_LOW(LED_PORT, LED_PIN)
#define LED_HI     PIN_HIGH(LED_PORT, LED_PIN)
#define LED_OUT    PIN_OUTPUT(LED_PORT, LED_PIN)

#if defined(USE_SERIAL_COMPLEX)
#include "serial_complex.h"
#elif defined(__AVR_ATxmega32A4U__) || defined(__AVR_ATxmega128A4U__)
#include "serial_xmega.h"
#define xchg8(x)     xchg8_1(x)
#define WriteCmd(x)  { CD_COMMAND; xchg8_1(x); CD_DATA; }
#define wait_ms(ms)  delay(ms)
#define write16(x)   { write16_N(x, 1); }
#define write24(x)   { write24_N(x, 1); }
#define WriteData(x) { write16(x); }

#else

#include <SPI.h>                //include before write16() macro
#warning Using Arduino SPI methods

#if defined(NINEBITS)
#define xchg8(x)     readbits(8)
#define WriteCmd(x)  { SDIO_OUTMODE(); MOSI_LO; SCK_HI; SCK_LO; write_8(x); }
#define WriteDat8(x) { MOSI_HI; SCK_HI; SCK_LO; write_8(x); }
#define INIT()  { CS_IDLE; RESET_IDLE; SETDDR; }
#define SDIO_INMODE()  MOSI_IN;SCK_OUT    //no braces
#define SDIO_OUTMODE() {MOSI_OUT;SCK_OUT;}
#else
#define xchg8(x)     xchg8_1(x)
#define WriteCmd(x)  { CD_COMMAND; xchg8_1(x); CD_DATA; }
#define INIT()  { CS_IDLE; RESET_IDLE; SETDDR; SPI.begin(); SPI.beginTransaction(settings); }
#define SDIO_INMODE()  SPI.endTransaction(); MOSI_IN;SCK_OUT    //no braces
#define SDIO_OUTMODE() {MOSI_OUT;SCK_OUT;SPI.beginTransaction(settings);}
#endif

#define wait_ms(ms)  delay(ms)
#define write16(x)   { write16_N(x, 1); }
#define write24(x)   { write24_N(x, 1); }
#define WriteData(x) { write16(x); }

static uint8_t spibuf[16];

#if 0
#else
#define CD_PIN     48 //DC
#define CS_PIN     53
#define RESET_PIN  49
#define SD_PIN     47 //sd-cs
#define MOSI_PIN   51
#define SCK_PIN    52
#endif

#define SETDDR  { CS_OUTPUT; CD_OUTPUT; RESET_OUTPUT; PIN_HIGH(SD_PORT, SD_PIN); PIN_OUTPUT(SD_PORT, SD_PIN); }

#define PIN_LOW(p, b)        digitalWrite(b, LOW)
#define PIN_HIGH(p, b)       digitalWrite(b, HIGH)
#define PIN_OUTPUT(p, b)     pinMode(b, OUTPUT)
#define PIN_INPUT(p, b)      pinMode(b, INPUT_PULLUP)
#define PIN_READ(p, b)       digitalRead(b)

#define FLUSH_IDLE { CS_IDLE; }

static SPISettings settings(8000000, MSBFIRST, SPI_MODE0);

static inline void write_8(uint8_t val)
{
    for (uint8_t i = 0; i < 8; i++) {   //send command
        if (val & 0x80) MOSI_HI;
	    else MOSI_LO;
		SCK_HI;
		SCK_LO;
        val <<= 1;
    }
}

static inline uint8_t xchg8_1(uint8_t x)
{
#if defined(DMA__STM32F1__)
    uint8_t ret;
	SPI.dmaTransfer(&x, &ret, 1);
	return ret;
#else
	return SPI.transfer(x);
#endif
}

static uint32_t readbits(uint8_t bits)
{
	uint32_t ret = 0;
	while (bits--) {
		ret <<= 1;
		if (PIN_READ(SPI_PORT, MOSI_PIN))
		    ret++;
		SCK_HI;
		SCK_LO;
	}
	return ret;
}

static inline void write16_N(uint16_t color, int16_t n)
{
#if defined(NINEBITS)
	uint8_t hi = color >> 8, lo = color;
	while (n-- > 0) {
		WriteDat8(hi);
		WriteDat8(lo);
	}
#elif defined(ESP8266) || defined(ESP32)
    uint8_t hilo[2];
	hilo[0] = color >> 8;
	hilo[1] = color;
	SPI.writePattern(hilo, 2, (uint32_t)n);
#elif defined(DMA__STM32F1__)
  SPI.setDataSize (SPI_CR1_DFF); // Set SPI 16bit mode
    SPI.dmaSend(&color, n, 0);
  SPI.setDataSize (0);
#elif defined(__STM32F1__)
    uint8_t buf[64];
	int cnt = (n > 32) ? 32 : n;
	uint8_t *p = buf;
	while (cnt--) { *p++ = color >> 8; *p++ = color; }
	while (n > 0) {
		cnt = (n > 32) ? 32 : n;
		SPI.write(buf, cnt << 1);
		n -= cnt;
	}
#elif 1
    uint8_t buf[64];
	while (n > 0) {
    	uint8_t *p = buf;
    	int cnt = (n > 32) ? 32 : n;
    	while (cnt--) { *p++ = color >> 8; *p++ = color; }
		cnt = (n > 32) ? 32 : n;
		SPI.transfer(buf, cnt << 1);
		n -= cnt;
	}
#else
	uint8_t hi = color >> 8, lo = color;
	while (n-- > 0) {
		SPI.transfer(hi);
		SPI.transfer(lo);
	}
#endif
}

static inline void write24_N(uint16_t color, int16_t n)
{
#if defined(NINEBITS)
	uint8_t r = color >> 8, g = (color >> 3), b = color << 3;
	while (n-- > 0) {
		WriteDat8(r);
		WriteDat8(g);
		WriteDat8(b);
	}
#elif defined(ESP8266) || defined(ESP32)
    uint8_t rgb[3];
	rgb[0] = color >> 8;
	rgb[1] = color >> 3;
	rgb[2] = color << 3;
	SPI.writePattern(rgb, 3, (uint32_t)n);
#else
	uint8_t r = color >> 8, g = (color >> 3), b = color << 3;
	while (n-- > 0) {
		SPI.transfer(r);
		SPI.transfer(g);
		SPI.transfer(b);
	}
#endif
}

static inline void write8_block(uint8_t * block, int16_t n, uint8_t bigend = 0)
{
#if defined(NINEBITS)
    while (n-- > 0) WriteDat8(*block++);
#elif defined(ESP8266) || defined(ESP32)
	SPI.writeBytes(block, (uint32_t)n);
#elif defined(DMA__STM32F1__)
    SPI.dmaSend(block, n, 1);
#elif defined(__STM32F1__)
	SPI.write(block, (uint32_t)n);
#elif defined(__SAMD21G18A__)
    Sercom *s = SERCOM1; 
	if (bigend) {
        n >>= 1;
        while (n--) {
	        uint8_t l = *block++, h = *block++;
			while (s->SPI.INTFLAG.bit.DRE == 0) ;
            s->SPI.DATA.bit.DATA = h;
			while (s->SPI.INTFLAG.bit.DRE == 0) ;
            s->SPI.DATA.bit.DATA = l;
        }	
	}
    else {	
	while (n--) {
	    while (s->SPI.INTFLAG.bit.DRE == 0) ;
        s->SPI.DATA.bit.DATA = *block++;
	}
    }
	while (s->SPI.INTFLAG.bit.TXC == 0) ;
    s->SPI.DATA.bit.DATA;
    s->SPI.DATA.bit.DATA;
#else
	SPI.transfer(block, n);
#endif
}

#if defined(__SAMD21G18A__)
static inline void spi_pattern(uint8_t * txbuf, uint16_t * rxbuf, int16_t n, int16_t rpt = 0)
{
    Sercom *s = SERCOM1;
	uint8_t cmd, reply;
    do {	
	    for (int i = n; i--; ) {
	        cmd = (txbuf == NULL) ? 0 : *txbuf++; 
			while (s->SPI.INTFLAG.bit.DRE == 0) ;
            s->SPI.DATA.bit.DATA = cmd;
			if (s->SPI.INTFLAG.bit.RXC) {
				reply = s->SPI.DATA.bit.DATA;
			    if (rxbuf) *rxbuf++ = reply;
            }
        }
	} while (--rpt > 0);
    while (s->SPI.INTFLAG.bit.TXC == 0) ;
    reply = s->SPI.DATA.bit.DATA;
    if (rxbuf) *rxbuf++ = reply;
}
#endif

#endif

//Screeen
#include <ILI9341_kbv.h>
ILI9341_kbv tft;
#define vali0 0   





//COLORS
#define  BLACK   0x0000
#define BLUE    0x001F
#define RED     0xF800
#define GREEN   0x07E0
#define CYAN    0x07FF
#define MAGENTA 0xF81F
#define YELLOW  0xFFE0
#define WHITE   0xFFFF

void setup()
          {
    
            tft.begin();
            tft.setRotation(1);// Landscape
            tft.fillScreen(TFT_PINK);// set color iitial screen 
 
          }
          



 
        
void loop(){

  //Some text to see on the screen 
      tft.setCursor(0, 0);
      tft.fillScreen(TFT_BLUE);
      tft.setTextColor(YELLOW); 
      tft.setTextSize(2);
      tft.print("YELLOW");
      tft.setTextSize(4);
      tft.setTextColor(RED); 
      tft.setTextSize(3);
      tft.print("RED");
      tft.setCursor(50, 50);
      tft.setTextColor(BLACK);    
      tft.setTextSize(8);
      tft.print("TEST");
      delay(3000);


  

}

Credits

roger_marin

6 projects • 13 followers

Tutorial for ILI9341 TFT LCD SD and Arduino MEGA (part 1)

Things used in this project

Hardware components

Story

Schematics

Connections

connections

Connections

Code

The Modify libray

The Program

Credits

roger_marin

Comments

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Tutorial for ILI9341 TFT LCD SD and Arduino MEGA (part 1)

Tutorial for ILI9341 TFT LCD SD and Arduino MEGA (part 1)

Things used in this project

Hardware components

Story

Schematics

Connections

connections

Connections

Code

The Modify libray

The Program

Credits

roger_marin

Comments