Accum-Tester/board/gmouse_lld_ADS7843_board.h

/*
 * This file is subject to the terms of the GFX License. If a copy of
 * the license was not distributed with this file, you can obtain one at:
 *
 *              http://ugfx.io/license.html
 */

#ifndef _GINPUT_LLD_MOUSE_BOARD_H
#define _GINPUT_LLD_MOUSE_BOARD_H

// Resolution and Accuracy Settings
#define GMOUSE_ADS7843_PEN_CALIBRATE_ERROR      8
#define GMOUSE_ADS7843_PEN_CLICK_ERROR          6
#define GMOUSE_ADS7843_PEN_MOVE_ERROR           4
#define GMOUSE_ADS7843_FINGER_CALIBRATE_ERROR  14
#define GMOUSE_ADS7843_FINGER_CLICK_ERROR      18
#define GMOUSE_ADS7843_FINGER_MOVE_ERROR       14

// How much extra data to allocate at the end of the GMouse structure for the board's use
#define GMOUSE_ADS7843_BOARD_DATA_SIZE          0

#define T_CS_HIGH    palSetPad(GPIOC, 13)
#define T_CS_LOW     palClearPad(GPIOC, 13)
#define T_SCK_HIGH   palSetPad(GPIOB, 0)
#define T_SCK_LOW    palClearPad(GPIOB, 0)
#define T_MOSI_HIGH  palSetPad(GPIOF, 11)
#define T_MOSI_LOW   palClearPad(GPIOF, 11)
#define T_MISO_LVL   palReadPad(GPIOB, 1)

/**
 * @brief   Initialise the board for the touch.
 *
 * @notapi
 *
 * ADS7843 (clone chip) is connected to this pins:
 * T_CS    GPIOC_PIN13
 * T_SCK   GPIOB_PIN0
 * T_MISO  GPIOB_PIN2
 * T_MOSI  GPIOF_PIN11
 * T_PEN   GPIOB_PIN1
 */
static gBool init_board(GMouse* m, unsigned driverinstance) {
  (void)m;
  (void)driverinstance;
/*
  palSetPadMode(GPIOC, 13, PAL_MODE_OUTPUT_PUSHPULL);
  palSetPadMode(GPIOB,  0, PAL_MODE_OUTPUT_PUSHPULL);
  palSetPadMode(GPIOB,  2, PAL_MODE_INPUT_PULLUP);
  palSetPadMode(GPIOF, 11, PAL_MODE_OUTPUT_PUSHPULL);
  palSetPadMode(GPIOB,  1, PAL_MODE_INPUT);
  * GPIO config must be done by board.h 
*/
  T_CS_HIGH;
  T_SCK_LOW;
  return true;
}

/**
 * @brief   Check whether the surface is currently touched
 * @return	TRUE if the surface is currently touched
 *
 * @notapi
 * PB1 is connected to TP_IRQ (low active).
*/
static GFXINLINE gBool getpin_pressed(GMouse* m) {
  (void)m;
  return (!palReadPad(GPIOB, T_PEN));
}

/**
 * @brief   Aquire the bus ready for readings
 *
 * @notapi
 * PC13 is connected to TP_CS (low active):
 */
static GFXINLINE void aquire_bus(GMouse* m) {
  (void)m;
  T_CS_LOW;
  T_SCK_LOW;
}

/**
 * @brief   Release the bus after readings
 *
 * @notapi
 */
static GFXINLINE void release_bus(GMouse* m) {
  (void)m;
  T_CS_HIGH;
}

/**
 * @brief   Write a value to touch controller
 * @return	none
 *
 * params[in] value	The value to be write.
 *
 * @notapi
 */
static GFXINLINE void write_value(GMouse* m, gU16 value) {
  (void)m;
  int i;

  for (i=8; i>0; i--) {
    T_SCK_LOW;
    if (value & 0x0080) {
      T_MOSI_HIGH;
    } else {
      T_MOSI_LOW;
    }
    asm("nop");
    value <<= 1;
    T_SCK_HIGH;
  }
}

/**
 * @brief   Read a value from touch controller
 * @return	The value read from the controller
 *
 * params[in] port	The controller port to read.
 *
 * @notapi
 */
static GFXINLINE gU16 read_value(GMouse* m, gU16 port) {
  (void)m;
  int i;
  gU16 data = 0;

  write_value(m, port);
  gfxSleepMicroseconds(6); //The conversion time of ADS7846 is up to 6us

  T_SCK_LOW;
  asm("nop"); // or gfxSleepMicroseconds(1) ?
  T_SCK_HIGH; //Give 1 clock, clear BUSY
  asm("nop");

  //Read 16-bit data, only the upper 12 bits are valid
  for (i=16; i>0; i--) {
    T_SCK_LOW;
    data <<= 1;
    asm("nop");
    T_SCK_HIGH;
    if (T_MISO_LVL) {
      data ++;
    }
  }

  data >>= 4;
  return data;
}

#endif /* _GINPUT_LLD_MOUSE_BOARD_H */