1 files changed, 145 insertions, 0 deletions
diff --git a/Display/XPT2046.cpp b/Display/XPT2046.cpp
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+++ b/Display/XPT2046.cpp
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+//******************************************************************************
+//  @file XPT2046.cpp
+//  @author Nicolai Shlapunov
+//
+//  @details DevCore: XPT2046 Low Level Driver Class, implementation
+//
+//  @copyright Copyright (c) 2016, Devtronic & Nicolai Shlapunov
+//             All rights reserved.
+//
+//  @section SUPPORT
+//
+//   Devtronic invests time and resources providing this open source code,
+//   please support Devtronic and open-source hardware/software by
+//   donations and/or purchasing products from Devtronic.
+//
+//******************************************************************************
+
+// *****************************************************************************
+// ***   Includes   ************************************************************
+// *****************************************************************************
+#include <XPT2046.h>
+
+// *****************************************************************************
+// ***   Init touchscreen   ****************************************************
+// *****************************************************************************
+void XPT2046::Init(void)
+{
+  // Pull down CS
+  HAL_GPIO_WritePin(TOUCH_CS_GPIO_Port, TOUCH_CS_Pin, GPIO_PIN_RESET);
+  // Send ON command
+  SpiWrite(TON);
+  // Send empty byte for skip answer
+  SpiWrite(EMP);
+  // Send empty byte for skip answer
+  SpiWrite(EMP);
+  // Pull up CS
+  HAL_GPIO_WritePin(TOUCH_CS_GPIO_Port, TOUCH_CS_Pin, GPIO_PIN_SET);
+}
+
+// *****************************************************************************
+// ***   If touched - return true.   *******************************************
+// *****************************************************************************
+bool XPT2046::IsTouch(void)
+{
+  // Check T_IRQ input and return state
+  return(HAL_GPIO_ReadPin(T_IRQ_GPIO_Port, T_IRQ_Pin) == GPIO_PIN_RESET);
+}
+
+// *****************************************************************************
+// ***   Get X and Y coordinates. If touched - return true.   ******************
+// *****************************************************************************
+bool XPT2046::GetRawXY(int32_t& x, int32_t& y)
+{
+  // Return value
+  bool ret = false;
+  // If touch present
+  if(HAL_GPIO_ReadPin(T_IRQ_GPIO_Port, T_IRQ_Pin) == GPIO_PIN_RESET)
+  {
+    // Pull down CS
+    HAL_GPIO_WritePin(TOUCH_CS_GPIO_Port, TOUCH_CS_Pin, GPIO_PIN_RESET);
+    // Request X coordinate
+    SpiWrite(CHX);
+    // Receive High byte for X
+    x = SpiWriteRead(EMP) << 8;
+    // Receive Low byte for X
+    x |= SpiWriteRead(EMP);
+    // Shift, because result have only 12 bits, 3 because answer started from
+    // second rise edge
+    x >>= 3;
+    // Pull up CS
+    HAL_GPIO_WritePin(TOUCH_CS_GPIO_Port, TOUCH_CS_Pin, GPIO_PIN_SET);
+
+    // Pull down CS
+    HAL_GPIO_WritePin(TOUCH_CS_GPIO_Port, TOUCH_CS_Pin, GPIO_PIN_RESET);
+    // Request Y coordinate
+    SpiWrite(CHY);
+    // Receive High byte for Y
+    y = SpiWriteRead(EMP) << 8;
+    // Receive Low byte for Y
+    y |= SpiWriteRead(EMP);
+    // Shift, because result have only 12 bits, 3 because answer started from
+    // second rise edge
+    y >>= 3;
+    // Pull up CS
+    HAL_GPIO_WritePin(TOUCH_CS_GPIO_Port, TOUCH_CS_Pin, GPIO_PIN_SET);
+
+    // Touch present
+    ret = true;
+  }
+  // Return result
+  return ret;
+}
+
+// *****************************************************************************
+// ***   Get X and Y coordinates. If touched - return true.   ******************
+// *****************************************************************************
+bool XPT2046::GetXY(int32_t& x, int32_t& y)
+{
+  // Return value
+  bool ret = GetRawXY(x, y);
+  // If touch present
+  if(ret)
+  {
+    // Calculate X
+    x = ((x * COEF) / kx) + bx;
+    // Calculate Y
+    y = ((y * COEF) / ky) + by;
+  }
+  // Return touch state
+  return ret;
+}
+
+// *****************************************************************************
+// ***   SetCalibrationConsts   ************************************************
+// *****************************************************************************
+void XPT2046::SetCalibrationConsts(int32_t nkx, int32_t nky, int32_t nbx, int32_t nby)
+{
+  // Save calibration constants
+  kx = nkx;
+  ky = nky;
+  bx = nbx;
+  by = nby;
+}
+
+// *****************************************************************************
+// ***   Write byte to SPI   ***************************************************
+// *****************************************************************************
+inline void XPT2046::SpiWrite(uint8_t c)
+{
+  // Call HAL function for send byte by SPI
+  (void) HAL_SPI_Transmit(hspi, &c, sizeof(c), 1U);
+}
+
+// *****************************************************************************
+// ***   Write and read byte to/from SPI   *************************************
+// *****************************************************************************
+inline uint8_t XPT2046::SpiWriteRead(uint8_t c)
+{
+  // Temporary variable for receive byte
+  uint8_t rcv;
+  // Call HAL function for send/receive byte by SPI
+  (void) HAL_SPI_TransmitReceive(hspi, &c, &rcv, sizeof(uint8_t), 1U);
+  // Return received byte
+  return rcv;
+}