/**
  ******************************************************************************
  * @file    gde021a1.c
  * @author  MCD Application Team
  * @version V1.0.2
  * @date    02-December-2014
  * @brief   This file includes the driver for GDE021A1 EPD (E Paper Display).
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT(c) 2014 STMicroelectronics</center></h2>
  *
  * Redistribution and use in source and binary forms, with or without modification,
  * are permitted provided that the following conditions are met:
  *   1. Redistributions of source code must retain the above copyright notice,
  *      this list of conditions and the following disclaimer.
  *   2. Redistributions in binary form must reproduce the above copyright notice,
  *      this list of conditions and the following disclaimer in the documentation
  *      and/or other materials provided with the distribution.
  *   3. Neither the name of STMicroelectronics nor the names of its contributors
  *      may be used to endorse or promote products derived from this software
  *      without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "gde021a1.h"

/** @addtogroup BSP
  * @{
  */ 

/** @addtogroup Components
  * @{
  */ 

/** @addtogroup GDE021A1
  * @brief      This file provides a set of functions needed to drive the
  *             GDE021A1 EPD (E Paper Display).
  * @{
  */

/** @defgroup GDE021A1_Private_TypesDefinitions
  * @{
  */ 
/**
  * @}
  */ 

/** @defgroup GDE021A1_Private_Defines
  * @{
  */
/**
  * @}
  */ 

/** @defgroup GDE021A1_Private_Macros
  * @{
  */
/**
  * @}
  */  

/** @defgroup GDE021A1_Private_Variables
  * @{
  */

/* Look-up table for the epaper (90 bytes) */
const unsigned char WF_LUT[]={
  0x82,0x00,0x00,0x00,0xAA,0x00,0x00,0x00,
  0xAA,0xAA,0x00,0x00,0xAA,0xAA,0xAA,0x00,
  0x55,0xAA,0xAA,0x00,0x55,0x55,0x55,0x55,
  0xAA,0xAA,0xAA,0xAA,0x55,0x55,0x55,0x55,
  0xAA,0xAA,0xAA,0xAA,0x15,0x15,0x15,0x15,
  0x05,0x05,0x05,0x05,0x01,0x01,0x01,0x01,
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
  0x41,0x45,0xF1,0xFF,0x5F,0x55,0x01,0x00,
  0x00,0x00,};

EPD_DrvTypeDef   gde021a1_drv =
{
  gde021a1_Init,
  gde021a1_WritePixel,
  gde021a1_SetDisplayWindow,
  gde021a1_RefreshDisplay,
  gde021a1_CloseChargePump,
  gde021a1_GetEpdPixelWidth,
  gde021a1_GetEpdPixelHeight,
  gde021a1_DrawImage,
};

/**
* @}
*/

/** @defgroup GDE021A1_Private_FunctionPrototypes
  * @{
  */
/**
* @}
*/ 

/** @defgroup GDE021A1_Private_Functions
  * @{
  */

/**
  * @brief  Initialize the GDE021A1 EPD Component.
  * @param  None
  * @retval None
  */
void gde021a1_Init(void)
{ 
  uint8_t nb_bytes = 0;

  /* Initialize the GDE021A11 */
  EPD_IO_Init();

  EPD_IO_WriteReg(EPD_REG_16);  /* Deep sleep mode disable */
  EPD_IO_WriteData(0x00);
  EPD_IO_WriteReg(EPD_REG_17);  /* Data Entry Mode Setting */
  EPD_IO_WriteData(0x03);
  EPD_IO_WriteReg(EPD_REG_68);  /* Set the RAM X start/end address */
  EPD_IO_WriteData(0x00);       /* RAM X address start = 00h */
  EPD_IO_WriteData(0x11);       /* RAM X adress end = 11h (17 * 4pixels by address = 72 pixels) */
  EPD_IO_WriteReg(EPD_REG_69);  /* Set the RAM Y start/end address */
  EPD_IO_WriteData(0x00);       /* RAM Y address start = 0 */
  EPD_IO_WriteData(0xAB);       /* RAM Y adress end = 171 */
  EPD_IO_WriteReg(EPD_REG_78);  /* Set RAM X Address counter */
  EPD_IO_WriteData(0x00);
  EPD_IO_WriteReg(EPD_REG_79);  /* Set RAM Y Address counter */
  EPD_IO_WriteData(0x00);
  EPD_IO_WriteReg(EPD_REG_240); /* Booster Set Internal Feedback Selection */
  EPD_IO_WriteData(0x1F);
  EPD_IO_WriteReg(EPD_REG_33);  /* Disable RAM bypass and set GS transition to GSA = GS0 and GSB = GS3 */
  EPD_IO_WriteData(0x03);
  EPD_IO_WriteReg(EPD_REG_44);  /* Write VCOMregister */
  EPD_IO_WriteData(0xA0);
  EPD_IO_WriteReg(EPD_REG_60);  /* Border waveform */
  EPD_IO_WriteData(0x64);
  EPD_IO_WriteReg(EPD_REG_50);  /* Write LUT register */
  
  for (nb_bytes=0; nb_bytes<90; nb_bytes++)
  {
    EPD_IO_WriteData(WF_LUT[nb_bytes]);
  }
}

/**
  * @brief  Writes 4 dots.
  * @param  HEX_Code: specifies the Data to write.
  * @retval None
  */
void gde021a1_WritePixel(uint8_t HEX_Code)
{
  /* Prepare the register to write data on the RAM */
  EPD_IO_WriteReg(EPD_REG_36);

  /* Send the data to write */
  EPD_IO_WriteData(HEX_Code);
}

/**
  * @brief  Sets a display window.
  * @param  Xpos: specifies the X bottom left position.
  * @param  Ypos: specifies the Y bottom left position.
  * @param  Width: display window width.
  * @param  Height: display window height.
  * @retval None
*/
void gde021a1_SetDisplayWindow(uint16_t Xpos, uint16_t Ypos, uint16_t Width, uint16_t Height)
{
  /* Set Y position and the height */
  EPD_IO_WriteReg(EPD_REG_68);
  EPD_IO_WriteData(Ypos);
  EPD_IO_WriteData(Height);
  /* Set X position and the width */
  EPD_IO_WriteReg(EPD_REG_69);
  EPD_IO_WriteData(Xpos);
  EPD_IO_WriteData(Width);
  /* Set the height counter */
  EPD_IO_WriteReg(EPD_REG_78);
  EPD_IO_WriteData(Ypos);
  /* Set the width counter */
  EPD_IO_WriteReg(EPD_REG_79);
  EPD_IO_WriteData(Xpos);
}

/**
  * @brief  Gets the EPD pixel Width.
  * @param  None
  * @retval The EPD Pixel Width
  */
uint16_t gde021a1_GetEpdPixelWidth(void)
{
  return GDE021A1_EPD_PIXEL_WIDTH;
}

/**
  * @brief  Gets the EPD pixel Height.
  * @param  None
  * @retval The EPD Pixel Height
  */
uint16_t gde021a1_GetEpdPixelHeight(void)
{
  return GDE021A1_EPD_PIXEL_HEIGHT;
}

/**
  * @brief  Writes to the selected EPD register.
  * @param  EPD_Reg: Address of the selected register.
  * @param  EPD_RegValue: value to write to the selected register.
  * @retval None
  */
void gde021a1_WriteReg(uint8_t EPD_Reg, uint8_t EPD_RegValue)
{
  EPD_IO_WriteReg(EPD_Reg);
  
  EPD_IO_WriteData(EPD_RegValue);
}

/**
  * @brief  Reads the selected EPD Register.
  * @param  EPD_Reg: address of the selected register
  * @retval EPD Register Value
  */
uint8_t gde021a1_ReadReg(uint8_t EPD_Reg)
{
  /* Write 8-bit Index (then Read Reg) */
  EPD_IO_WriteReg(EPD_Reg);
  
  /* Read 8-bit Reg */
  return (EPD_IO_ReadData());
}

/**
  * @brief  Activates display update sequence.
  * @param  None
  * @retval None
  */
void gde021a1_RefreshDisplay(void)
{
  /* Write on the Display update control register */
  EPD_IO_WriteReg(EPD_REG_34);
  
  /* Display update data sequence option */
  EPD_IO_WriteData(0xC4);

  /* Launching the update: Nothing should interrupt this sequence in order
     to avoid display corruption */
  EPD_IO_WriteReg(EPD_REG_32);
}

/**
  * @brief  Disables the clock and the charge pump.
  * @param  None
  * @retval None
  */
void gde021a1_CloseChargePump(void)
{
  /* Write on the Display update control register */
  EPD_IO_WriteReg(EPD_REG_34);

  /* Disable CP then Disable Clock signal */  
  EPD_IO_WriteData(0x03);

  /* Launching the update: Nothing should interrupt this sequence in order
     to avoid display corruption */
  EPD_IO_WriteReg(EPD_REG_32);
}

/**
  * @brief  Displays picture..
  * @param  pdata: picture address.
  * @param  Xpos:  Image X position in the EPD
  * @param  Ypos:  Image Y position in the EPD
  * @param  Xsize: Image X size in the EPD
  * @note   Xsize have to be a multiple of 4 
  * @param  Ysize: Image Y size in the EPD
  * @retval None
  */
void gde021a1_DrawImage(uint16_t Xpos, uint16_t Ypos, uint16_t Xsize, uint16_t Ysize, uint8_t *pdata)
{
  uint32_t i, j = 0;
  uint8_t pixels_4 = 0;
  uint8_t pixels_4_grey[4] = {0};
  uint8_t nb_4_pixels, data_res = 0;
  
  /* Prepare the register to write data on the RAM */
  EPD_IO_WriteReg(EPD_REG_36);
  
  /* X size is a multiple of 8 */
  if ((Xsize % 8) == 0)
  {
    for (i= 0; i< ((((Ysize) * (Xsize/4)))/2) ; i++)
    {
      /* Get the current data */
      pixels_4 = pdata[i];
      if (pixels_4 !=0)
      {
        /* One byte read codes 8 pixels in 1-bit bitmap */
        for (nb_4_pixels = 0; nb_4_pixels < 2; nb_4_pixels++)
        {
          /* Processing 8 pixels */
          /* Preparing the 4 pixels coded with 4 grey level per pixel
             from a monochrome xbm file */
          for (j= 0; j<4; j++)
          {
            if (((pixels_4) & 0x01) == 1)
            {
              /* Two LSB is coding black in 4 grey level */
              pixels_4_grey[j] &= 0xFC;
            }
            else
            {
              /* Two LSB is coded white in 4 grey level */
              pixels_4_grey[j] |= 0x03;
            }
            pixels_4 = pixels_4 >> 1;	
          }
          
          /* Processing 4 pixels */
          /* Format the data to have the Lower pixel number sent on the MSB for the SPI to fit with the RAM 
             EPD topology */
          data_res = pixels_4_grey[0] << 6 | pixels_4_grey[1] << 4 | pixels_4_grey[2] << 2 | pixels_4_grey[3] << 0;
          
          /* Send the data to the EPD's RAM through SPI */
          EPD_IO_WriteData(data_res);
        }
      }
      else
      {	
        /* 1 byte read from xbm files is equivalent to 8 pixels in the 
           other words 2 bytes to be transferred */
        EPD_IO_WriteData(0xFF);
        EPD_IO_WriteData(0xFF);
      }
    }
  }
  
  /* X size is a multiple of 4 */
  else  
  {
    for (i= 0; i< ((((Ysize) * ((Xsize/4)+1))/2)) ; i++)
    {
      /* Get the current data */
      pixels_4 = pdata[i];
      if (((i+1) % (((Xsize/4)+1)/2)) != 0)
      {
        if (pixels_4 !=0)
        {
          /* One byte read codes 8 pixels in 1-bit bitmap */
          for (nb_4_pixels = 0; nb_4_pixels < 2; nb_4_pixels++)
          {
            /* Processing 8 pixels */
            /* Preparing the 4 pixels coded with 4 grey level per pixel
               from a monochrome xbm file */
            for (j= 0; j<4; j++)
            {
              if (((pixels_4) & 0x01) == 1)
              {
                /* Two LSB is coding black in 4 grey level */
                pixels_4_grey[j] &= 0xFC;
              }
              else
              {
                /* Two LSB is coded white in 4 grey level */
                pixels_4_grey[j] |= 0x03;
              }
              pixels_4 = pixels_4 >> 1;
            }
            
            /* Processing 4 pixels */
            /* Format the data to have the Lower pixel number sent on the MSB for the SPI to fit with the RAM 
               EPD topology */
            data_res = pixels_4_grey[0] << 6 | pixels_4_grey[1] << 4 | pixels_4_grey[2] << 2 | pixels_4_grey[3] << 0;
            
            /* Send the data to the EPD's RAM through SPI */
            EPD_IO_WriteData(data_res);
          }
        }
        else if (pixels_4 == 0)
        {
          /* One byte read from xbm files is equivalent to 8 pixels in the 
             other words Two bytes to be transferred */
          EPD_IO_WriteData(0xFF);
          EPD_IO_WriteData(0xFF);
        }
      }
      
      else if (((i+1) % (((Xsize/4)+1)/2)) == 0)
      {
        if (pixels_4 !=0xf0)
        {
          /* Processing 8 pixels */
          /* Preparing the 4 pixels coded with 4 grey level per pixel
             from a monochrome xbm file */
          for (j= 0; j<4; j++)
          {
            if (((pixels_4) & 0x01) == 1)
            {
              /* 2 LSB is coding black in 4 grey level */
              pixels_4_grey[j] &= 0xFC;
            }
            else
            {
              /* 2 LSB is coded white in 4 grey level */
              pixels_4_grey[j] |= 0x03;
            }
            pixels_4 = pixels_4 >> 1;	
          }
          
          /* Processing 4 pixels */
          /* Format the data to have the Lower pixel number sent on the MSB for the SPI to fit with the RAM 
             EPD topology */
          data_res = pixels_4_grey[0] << 6 | pixels_4_grey[1] << 4 | pixels_4_grey[2] << 2 | pixels_4_grey[3] << 0;
          
          /* Send the data to the EPD's RAM through SPI */
          EPD_IO_WriteData(data_res);
        }
        else if (pixels_4 == 0xf0)
        {
          /* One byte to be transferred */
          EPD_IO_WriteData(0xFF);
        }
      }
    }
  }
}

/**
  * @}
  */ 

/**
  * @}
  */  

/**
  * @}
  */ 

/**
  * @}
  */ 

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
