// * Project Name:
//     TouchPanel (Demo for working with TouchPanel Controller)
// * Target Platform:
//     PIC
// * Copyright:
//     (c) mikroElektronika, 2007.
// * Revision History:
//     20071225:
//       - Initial release.
// * Description:
//     this code in intended to work with TouchPanel and GLCD
//     Target devices are PIC16 and PIC18 family MCU's, any speed.
// * Test configuration:
//     MCU:             PIC16F887
//     Dev.Board:       EasyPic5
//     Oscillator:      HS, 8.000MHz
//     Ext. Modules:    TouchPanel, GLCD
//     SW:              mikroC v8.0
// * NOTES:
//     - Turn off PORTA LEDs, 7Seg Display Switches, ADC jumpers and PORTA pull-up/down resistors.
//     - Turn on GLCD backlight and TouchPanel Contoller switches on EasyPIC5 board.


char write_erase, pen_size;
unsigned int x_coord, y_coord;
long         x_coord128, y_coord64;                       // scaled x-y position
int          cal_x_min, cal_y_min, cal_x_max, cal_y_max;  // calibration constants
char write_msg[] = "WRITE";                               // GLCD menu messages
char clear_msg[] = "CLEAR";
char erase_msg[] = "ERASE";
const unsigned int ADC_THRESHOLD = 900;                   // Threshold value for press detecting

// returns 1 if TouchPanel is pressed, 0 otherwise
char PressDetect() {
  unsigned adc_rd;
  char result;

  // PRESS detecting
  PORTC.F0 = 0;         // DRIVEA = 0 (LEFT drive off, RIGHT drive off, TOP drive on)
  PORTC.F1 = 0;         // DRIVEB = 0 (BOTTOM drive off)
  Delay_us(3500);

  adc_rd = ADC_read(1);                                   // Read RA1 (READ-Y)

  result = (adc_rd > ADC_THRESHOLD);                      // if logical one is detectet
  
  //debouncing, repeat detecting after 2ms
  Delay_ms(2);
  adc_rd = ADC_read(1);
  result = result & (adc_rd > ADC_THRESHOLD);
  return result;
}

unsigned int GetX() {
  unsigned int result;
  //reading X
  PORTC.F0 = 1;         // DRIVEA = 1 (LEFT drive on, RIGHT drive on, TOP drive off)
  PORTC.F1 = 0;         // DRIVEB = 0 (BOTTOM drive off)

  Delay_ms(5);
  result = ADC_read(0); // reading X value from RA0 (BOTTOM)
  return result;
}

unsigned int GetY() {
  unsigned int result;
  //reading Y
  PORTC.F0 = 0;         // DRIVEA = 0 (LEFT drive off, RIGHT drive off, TOP drive on)
  PORTC.F1 = 1;         // DRIVEB = 1 (BOTTOM drive on)

  Delay_ms(5);
  result = ADC_read(1); // reading Y value from RA1 (from LEFT)
  return result;
}

void Calibrate() {

  Glcd_Dot(0,63,1);
  Glcd_Write_Text("TOUCH BOTTOM LEFT",10,3,1);

  while (!PressDetect());
  
  // get calibration constants (reading and compensating TouchPanel nonlinearity)
  cal_x_min = GetX() - 10;
  cal_y_min = GetY() - 10;
  Delay_ms(1000);

  Glcd_Fill(0);
  Glcd_Dot(127,0,1);
  Glcd_Write_Text("TOUCH UPPER RIGHT",10,4,1);
  while (!PressDetect()) ;

  // get calibration constants (reading and compensating TouchPanel nonlinearity)
  cal_x_max = GetX() + 5;
  cal_y_max = GetY() + 5;
  Delay_ms(1000);
}


void main() {
  PORTA  = 0x00;
  TRISA  = 0x03;                               // RA0 i RA1 are analog inputs
  ANSEL  = 0x03;
  
  ANSELH = 0;                                  // Configure other AN pins as digital I/O

  PORTC  = 0 ;
  TRISC  = 0 ;                                 // PORTC is output

  Glcd_Init(&PORTB, 0, 1, 2, 3, 5, 4, &PORTD); // Glcd_Init_EP5, see Autocomplete

  Glcd_Fill(0);
  Glcd_Set_Font(FontSystem5x8, 5, 8, 32);
  Glcd_Write_Text("CALIBRATION", 24, 3, 1);
  Delay_ms(1500);

  Glcd_Fill(0);
  Calibrate();
  Glcd_Fill(0);

  Glcd_Write_Text("WRITE ON SCREEN", 24, 4, 1) ;
  Delay_ms(1000);
  Glcd_Fill(0);
  
  Glcd_Fill(0);
  Glcd_V_Line(0,7,0,1);
  Glcd_Write_Text(clear_msg,1,0,0);
  Glcd_V_Line(0,7,97,1);
  Glcd_Write_Text(erase_msg,98,0,0);

  //Pen Menu:
  Glcd_Rectangle(41,0,52,9,1);
  Glcd_Box(45,3,48,6,1);
  Glcd_Rectangle(63,0,70,7,1);
  Glcd_Box(66,3,67,4,1);
  Glcd_Rectangle(80,0,86,6,1);
  Glcd_Dot(83,3,1);

  write_erase = 1;
  pen_size = 1;
  
  while (1) {
  
    if (PressDetect()) {
      // after a PRESS is detected read X-Y and convert it to 128x64 space
      x_coord = GetX() - cal_x_min;
      y_coord = GetY() - cal_y_min;

      x_coord128 = (x_coord * 128l) / (cal_x_max - cal_x_min);
      y_coord64 = (64 -(y_coord *64) / (cal_y_max - cal_y_min));

      if ((x_coord128 < 0) || (x_coord128 > 127))
         continue;
      if ((y_coord64 < 0) || (y_coord64 > 63))
         continue;


      //if clear is pressed
      if ((x_coord128 < 31) && (y_coord64 < 8)) {

         Glcd_Fill(0);

         //Pen Menu:
         Glcd_Rectangle(41,0,52,9,1);
         Glcd_Box(45,3,48,6,1);
         Glcd_Rectangle(63,0,70,7,1);
         Glcd_Box(66,3,67,4,1);
         Glcd_Rectangle(80,0,86,6,1);
         Glcd_Dot(83,3,1);

         Glcd_V_Line(0,7,0,1);
         Glcd_Write_Text(clear_msg,1,0,0);
         Glcd_V_Line(0,7,97,1);
         if (write_erase)
           Glcd_Write_Text(erase_msg,98,0,0);
         else
           Glcd_Write_Text(write_msg,98,0,0);
         }
         
      //if write/erase is pressed
      if ((x_coord128 > 96) && (y_coord64 < 8)) {
         if (write_erase) {
           write_erase = 0;
           Glcd_Write_Text(write_msg,98,0,0);
           Delay_ms(500);
           }
         else {
           write_erase = 1;
           Glcd_Write_Text(erase_msg,98,0,0);
           Delay_ms(500);
           }
         }
         
      //if pen size is selected
      if ((x_coord128 >= 41) && (x_coord128 <= 52) && (y_coord64 <= 9))
         pen_size = 3;

      if ((x_coord128 >= 63) && (x_coord128 <= 70) && (y_coord64 <= 7))
         pen_size = 2;

      if ((x_coord128 >= 80) && (x_coord128 <= 86) && (y_coord64 <= 6))
         pen_size = 1;

      if (y_coord64 < 11)
         continue;

      switch (pen_size) {
         case 1 : Glcd_Dot(x_coord128, y_coord64, write_erase); break;
         case 2 : Glcd_Box(x_coord128, y_coord64, x_coord128 + 1, y_coord64 + 1, write_erase); break;
         case 3 : Glcd_Box(x_coord128-1, y_coord64-1, x_coord128 + 2, y_coord64 + 2, write_erase); break;
         }
         
      }
    }
}