Step 1: Scetch

#include // Core graphics library

#include // Hardware-specific library #include

#define YP A1 // must be an analog pin, use "An" notation! #define XM A2 // must be an analog pin, use "An" notation! #define YM 7 // can be a digital pin #define XP 6 // can be a digital pin

#define TS_MINX 150 #define TS_MINY 120 #define TS_MAXX 920 #define TS_MAXY 940

// For better pressure precision, we need to know the resistance // between X+ and X- Use any multimeter to read it // For the one we're using, its 300 ohms across the X plate TouchScreen ts = TouchScreen(XP, YP, XM, YM, 300);

// Assign human-readable names to some common 16-bit color values: #define BLACK 0x0000 #define BLUE 0x001F #define RED 0xF800 #define GREEN 0x07E0 #define CYAN 0x07FF #define MAGENTA 0xF81F #define YELLOW 0xFFE0 #define WHITE 0xFFFF

SWTFT tft;

#define BOXSIZE 40 #define PENRADIUS 3 int oldcolor, currentcolor;

void setup(void) { Serial.begin(9600); Serial.println(F("Paint!")); tft.reset(); uint16_t identifier = tft.readID();

Serial.print(F("LCD driver chip: ")); Serial.println(identifier, HEX);

tft.begin(identifier);

tft.fillScreen(BLACK);

tft.fillRect(0, 0, BOXSIZE, BOXSIZE, RED); tft.fillRect(BOXSIZE, 0, BOXSIZE, BOXSIZE, YELLOW); tft.fillRect(BOXSIZE*2, 0, BOXSIZE, BOXSIZE, GREEN); tft.fillRect(BOXSIZE*3, 0, BOXSIZE, BOXSIZE, CYAN); tft.fillRect(BOXSIZE*4, 0, BOXSIZE, BOXSIZE, BLUE); tft.fillRect(BOXSIZE*5, 0, BOXSIZE, BOXSIZE, MAGENTA); // tft.fillRect(BOXSIZE*6, 0, BOXSIZE, BOXSIZE, WHITE); tft.drawRect(0, 0, BOXSIZE, BOXSIZE, WHITE); currentcolor = RED; pinMode(13, OUTPUT); }

#define MINPRESSURE 10 #define MAXPRESSURE 1000

void loop() { digitalWrite(13, HIGH); // Recently Point was renamed TSPoint in the TouchScreen library // If you are using an older version of the library, use the // commented definition instead. Point p = ts.getPoint(); // TSPoint p = ts.getPoint(); digitalWrite(13, LOW);

// if sharing pins, you'll need to fix the directions of the touchscreen pins //pinMode(XP, OUTPUT); pinMode(XM, OUTPUT); pinMode(YP, OUTPUT); //pinMode(YM, OUTPUT);

// we have some minimum pressure we consider 'valid' // pressure of 0 means no pressing!

if (p.z > MINPRESSURE && p.z < MAXPRESSURE) { /* Serial.print("X = "); Serial.print(p.x); Serial.print("\tY = "); Serial.print(p.y); Serial.print("\tPressure = "); Serial.println(p.z); */ if (p.y < (TS_MINY-5)) { Serial.println("erase"); // press the bottom of the screen to erase tft.fillRect(0, BOXSIZE, tft.width(), tft.height()-BOXSIZE, BLACK); } // scale from 0->1023 to tft.width p.x = tft.width()-(map(p.x, TS_MINX, TS_MAXX, tft.width(), 0)); p.y = tft.height()-(map(p.y, TS_MINY, TS_MAXY, tft.height(), 0)); /* Serial.print("("); Serial.print(p.x); Serial.print(", "); Serial.print(p.y); Serial.println(")"); */ if (p.y < BOXSIZE) { oldcolor = currentcolor;

if (p.x < BOXSIZE) { currentcolor = RED; tft.drawRect(0, 0, BOXSIZE, BOXSIZE, WHITE); } else if (p.x < BOXSIZE*2) { currentcolor = YELLOW; tft.drawRect(BOXSIZE, 0, BOXSIZE, BOXSIZE, WHITE); } else if (p.x < BOXSIZE*3) { currentcolor = GREEN; tft.drawRect(BOXSIZE*2, 0, BOXSIZE, BOXSIZE, WHITE); } else if (p.x < BOXSIZE*4) { currentcolor = CYAN; tft.drawRect(BOXSIZE*3, 0, BOXSIZE, BOXSIZE, WHITE); } else if (p.x < BOXSIZE*5) { currentcolor = BLUE; tft.drawRect(BOXSIZE*4, 0, BOXSIZE, BOXSIZE, WHITE); } else if (p.x < BOXSIZE*6) { currentcolor = MAGENTA; tft.drawRect(BOXSIZE*5, 0, BOXSIZE, BOXSIZE, WHITE); }

if (oldcolor != currentcolor) { if (oldcolor == RED) tft.fillRect(0, 0, BOXSIZE, BOXSIZE, RED); if (oldcolor == YELLOW) tft.fillRect(BOXSIZE, 0, BOXSIZE, BOXSIZE, YELLOW); if (oldcolor == GREEN) tft.fillRect(BOXSIZE*2, 0, BOXSIZE, BOXSIZE, GREEN); if (oldcolor == CYAN) tft.fillRect(BOXSIZE*3, 0, BOXSIZE, BOXSIZE, CYAN); if (oldcolor == BLUE) tft.fillRect(BOXSIZE*4, 0, BOXSIZE, BOXSIZE, BLUE); if (oldcolor == MAGENTA) tft.fillRect(BOXSIZE*5, 0, BOXSIZE, BOXSIZE, MAGENTA); } } if (((p.y-PENRADIUS) > BOXSIZE) && ((p.y+PENRADIUS) < tft.height())) { tft.fillCircle(p.x, p.y, PENRADIUS, currentcolor); } } }