'XP' was not declared in this scope

My code is this,(Highlighted where I think the problem is)

#include <stdint.h>
#include <TouchScreen.h>
#include <TFT.h>
#include <SPI.h>

#ifdef SEEEDUINO
#define YP A2 // must be an analog pin, use "An" notation!
#define XM A1 // must be an analog pin, use "An" notation!
#define YM A0 // can be a digital pin, this is A0
#define XP A3 // can be a digital pin, this is A3
#endif

#ifdef MEGA
#define YP A2 // must be an analog pin, use "An" notation!
#define XM A1 // must be an analog pin, use "An" notation!
#define YM 54 // can be a digital pin, this is A0
#define XP 57 // can be a digital pin, this is A3
#endif

//Measured ADC values for (0,0) and (240-1,320-1)
//TS_MINX corresponds to ADC value when X = 0
//TS_MINY corresponds to ADC value when Y = 0
//TS_MAXX corresponds to ADC value when X = 240 -1
//TS_MAXY corresponds to ADC value when Y = 320 -1

#define TS_MINX 140
#define TS_MAXX 900

#define TS_MINY 120
#define TS_MAXY 940

#define XMARK 1
#define OMARK 0
#define NOMARK -1
#define DRAW -2

int Board[10];
int turndicator = OMARK;

// For better pressure precision, we need to know the resistance
// between X+ and X- Use any multimeter to read it
// The 2.8" TFT Touch shield has 300 ohms across the X plate

TouchScreen ts = TouchScreen(XP, YP, XM, YM, 300);
void setup()
{
Tft.init(); //init TFT library
DrawSplash();
delay(3000);
ResetGame();
}

void DrawSplash() {
DrawBoard();
drawX(5);
delay(500);
drawO(1);
delay(500);
drawX(4);
delay(500);
drawO(3);
delay(500);
drawX(6);
Tft.drawString ("TIC-TAC-TOE", 30,152,2, WHITE);
}

void loop() {
int MapX1 = 239;
int MapX2 = 0;
int MapY1 = 319;
int MapY2 = 0;

// a point object holds x y and z coordinates
Point p = ts.getPoint();

p.x = map(p.x, TS_MINX, TS_MAXX, MapX1, MapX2);
p.y = map(p.y, TS_MINY, TS_MAXY, MapY1, MapY2);

// we have some minimum pressure we consider 'valid'
// pressure of 0 means no pressing!
if (p.z > ts.pressureThreshhold)
{
//p.x;
//p.y;
//p.z;

int pos = GetFingerPos(p.x,p.y);
if (Board[pos] == -1) {
if (turndicator == OMARK ) {
drawO(pos);
Board[pos] = turndicator;
turndicator = XMARK;
} else {
drawX(pos);
Board[pos] = turndicator;
turndicator = OMARK;
}
int winner = CheckWinner();
if (winner != NOMARK) {
if (winner == XMARK) { Tft.drawString ("X WINS", 20,152,4, BLUE); }
if (winner == OMARK) { Tft.drawString ("O WINS", 22,152,4, BLUE); }
if (winner == DRAW) { Tft.drawString ("DRAW", 35,152,5,BLUE); }
delay(2000);
ResetGame();
}
}
// Tft.fillCircle(p.x,p.y,2,GREEN);
}
}

int CheckWinner() {

int winner = NOMARK;
//Surely there is a better way?

//Across
if (Board[1] == Board[2] && Board[1] == Board[3] && winner == NOMARK) {winner=Board[1]; }
if (Board[4] == Board[5] && Board[4] == Board[6] && winner == NOMARK) {winner=Board[4]; }
if (Board[7] == Board[8] && Board[7] == Board[9] && winner == NOMARK) {winner=Board[7]; }

//down
if (Board[1] == Board[4] && Board[1] == Board[7] && winner == NOMARK) {winner=Board[1]; }
if (Board[2] == Board[5] && Board[2] == Board[8] && winner == NOMARK) {winner=Board[2]; }
if (Board[3] == Board[6] && Board[3] == Board[9] && winner == NOMARK) {winner=Board[3]; }

//diagonal
if (Board[1] == Board[5] && Board[1] == Board[9] && winner == NOMARK) {winner=Board[1]; }
if (Board[3] == Board[5] && Board[3] == Board[7] && winner == NOMARK) {winner=Board[3]; }

// finally, check and see if all of the spaces are occupied..
if (winner == NOMARK && Board[1] > -1 && Board[2] > -1 && Board[3] > -1 && Board[4] > -1 && Board[5] > -1 && Board[6] > -1 && Board[7] > -1 && Board[8] > -1 && Board[9] > -1 ) { winner = DRAW; }

return winner;
}

void ResetGame() {
DrawBoard(); // Draw the board
for (int i=0;i<10;i++) { Board = NOMARK; }
}
void DrawBoard() {
// I draw the game board First, blank the screen Then draw the board
// X blocks are 80px wide
// y blocks are 106px wide
*// x's and o's are 75% of block width, so call it 60x60 square. *

  • Tft.fillRectangle(0,0,239,319,BLACK);*
  • Tft.drawLine(0,106,239,106,GREEN); *
  • Tft.drawLine(0,212,239,212,GREEN); *
  • Tft.drawLine(80,0,80,319,GREEN); *
  • Tft.drawLine(160,0,160,319,GREEN); *
    }
    int GetFingerPos(int x, int y) {
  • int row =0;*
  • int col =0;*
  • col = x/80;*
  • row = y/106;*
    _ int pos = row * 3 + col +1 ;_
    return pos;
    }
    void drawX(int pos) {
    // I draw an X at an arbitrary position on the screen
  • Tft.drawLine(getCenterX(pos)-30,getCentery(pos)-30, getCenterX(pos)+30, getCentery(pos)+30,RED);*
  • Tft.drawLine(getCenterX(pos)+30,getCentery(pos)-30, getCenterX(pos)-30, getCentery(pos)+30,RED);*
    }
    void drawO(int pos) {
  • Tft.drawCircle(getCenterX(pos),getCentery(pos), 30 ,RED);*
    }
    int getCenterX( int pos ) {
    // I return the center x position for a given spot on the board.
    if (pos == 1) return 40;
    if (pos == 4) return 40;
    if (pos == 7) return 40;
    if (pos == 2) return 120;
    if (pos == 5) return 120;
    if (pos == 8) return 120;
    if (pos == 3) return 200;
    if (pos == 6) return 200;
    if (pos == 9) return 200;
    }
    int getCentery ( int pos ) {
    // I return the center y position for a given spot on the board.
    if (pos == 1) return 53;
    if (pos == 2) return 53;
    if (pos == 3) return 53;
    if (pos == 4) return 159;
    if (pos == 5) return 159;
    if (pos == 6) return 159;
    if (pos == 7) return 265;
    if (pos == 8) return 265;
    if (pos == 9) return 265;
    }
    for some reason the reply I get when I am compiling it is 'XP' was not declared in this scope
    Tic_Tac_Toe.ino (5.67 KB)

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Please always do a Tools > Auto Format on your code before posting it. This will make it easier for you to spot bugs and make it easier for us to read. If you're using the Arduino Web Editor you will not have access to this useful tool. I recommend you to use the standard IDE instead.

It seems clear that the problem is neither SEEEDUINO or MEGA are defined. Where do you expect these macros to be defined? Maybe you're thinking of the board identification macros that are commonly defined by Arduino hardware packages? For example if you select Tools > Board > Arduino/Genuino Mega or Mega 2560 and Tools > Processor > ATmega2560 then ARDUINO_AVR_MEGA2560 will be defined. If you select Tools > Board > Arduino/Genuino Mega or Mega 2560 and Tools > Processor > ATmega1280 then ARDUINO_AVR_MEGA will be defined. There will be something similar defined in the Seeduino hardware package.