e-paper-display/bcm2835-1.71/e-Paper/Arduino/epd4in2b_V2/epd4in2b_V2.cpp

/**
 *  @filename   :   epd4in2b_V2.cpp
 *  @brief      :   Implements for Dual-color e-paper library
 *  @author     :	Yehui from Waveshare
 *
 *  Copyright (C) Waveshare     Nov 25 2020
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documnetation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to  whom the Software is
 * furished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS OR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <stdlib.h>
#include "epd4in2b_V2.h"

Epd::~Epd() {
};

Epd::Epd() {
    reset_pin = RST_PIN;
    dc_pin = DC_PIN;
    cs_pin = CS_PIN;
    busy_pin = BUSY_PIN;
    width = EPD_WIDTH;
    height = EPD_HEIGHT;
};

int Epd::Init(void) {
    /* this calls the peripheral hardware interface, see epdif */
    if (IfInit() != 0) {
        return -1;
    }
    /* EPD hardware init start */
    Reset();

    SendCommand(POWER_ON);
    WaitUntilIdle();
	
    SendCommand(PANEL_SETTING);
    SendData(0x0F);     // LUT from OTP
	
    /* EPD hardware init end */
    return 0;
}

/**
 *  @brief: basic function for sending commands
 */
void Epd::SendCommand(unsigned char command) {
    DigitalWrite(dc_pin, LOW);
    SpiTransfer(command);
}

/**
 *  @brief: basic function for sending data
 */
void Epd::SendData(unsigned char data) {
    DigitalWrite(dc_pin, HIGH);
    SpiTransfer(data);
}

/**
 *  @brief: Wait until the busy_pin goes HIGH
 */
void Epd::WaitUntilIdle(void) {
    while(DigitalRead(busy_pin) == 0) {      //0: busy, 1: idle
        DelayMs(100);
    }      
}

/**
 *  @brief: module reset. 
 *          often used to awaken the module in deep sleep, 
 *          see Epd::Sleep();
 */
void Epd::Reset(void) {
    DigitalWrite(reset_pin, HIGH);
    DelayMs(200);   
    DigitalWrite(reset_pin, LOW);
    DelayMs(2);
    DigitalWrite(reset_pin, HIGH);
    DelayMs(200);   
}

/**
 *  @brief: transmit partial data to the SRAM
 */
void Epd::SetPartialWindow(const unsigned char* buffer_black, const unsigned char* buffer_red, int x, int y, int w, int l) {
    SendCommand(PARTIAL_IN);
    SendCommand(PARTIAL_WINDOW);
    SendData(x >> 8);
    SendData(x & 0xf8);     // x should be the multiple of 8, the last 3 bit will always be ignored
    SendData(((x & 0xf8) + w  - 1) >> 8);
    SendData(((x & 0xf8) + w  - 1) | 0x07);
    SendData(y >> 8);        
    SendData(y & 0xff);
    SendData((y + l - 1) >> 8);        
    SendData((y + l - 1) & 0xff);
    SendData(0x01);         // Gates scan both inside and outside of the partial window. (default) 
    DelayMs(2);
    SendCommand(DATA_START_TRANSMISSION_1);
    if (buffer_black != NULL) {
        for(int i = 0; i < w  / 8 * l; i++) {
            SendData(buffer_black[i]);  
        }  
    }
    DelayMs(2);
    SendCommand(DATA_START_TRANSMISSION_2);
    if (buffer_red != NULL) {
        for(int i = 0; i < w  / 8 * l; i++) {
            SendData(buffer_red[i]);  
        }  
    }
    DelayMs(2);
    SendCommand(PARTIAL_OUT);  
}

/**
 *  @brief: transmit partial data to the black part of SRAM
 */
void Epd::SetPartialWindowBlack(const unsigned char* buffer_black, int x, int y, int w, int l) {
    SendCommand(PARTIAL_IN);
    SendCommand(PARTIAL_WINDOW);
    SendData(x >> 8);
    SendData(x & 0xf8);     // x should be the multiple of 8, the last 3 bit will always be ignored
    SendData(((x & 0xf8) + w  - 1) >> 8);
    SendData(((x & 0xf8) + w  - 1) | 0x07);
    SendData(y >> 8);        
    SendData(y & 0xff);
    SendData((y + l - 1) >> 8);        
    SendData((y + l - 1) & 0xff);
    SendData(0x01);         // Gates scan both inside and outside of the partial window. (default) 
    DelayMs(2);
    SendCommand(DATA_START_TRANSMISSION_1);
    if (buffer_black != NULL) {
        for(int i = 0; i < w  / 8 * l; i++) {
            SendData(buffer_black[i]);  
        }  
    }
    DelayMs(2);
    SendCommand(PARTIAL_OUT);  
}

/**
 *  @brief: transmit partial data to the red part of SRAM
 */
void Epd::SetPartialWindowRed(const unsigned char* buffer_red, int x, int y, int w, int l) {
    SendCommand(PARTIAL_IN);
    SendCommand(PARTIAL_WINDOW);
    SendData(x >> 8);
    SendData(x & 0xf8);     // x should be the multiple of 8, the last 3 bit will always be ignored
    SendData(((x & 0xf8) + w  - 1) >> 8);
    SendData(((x & 0xf8) + w  - 1) | 0x07);
    SendData(y >> 8);        
    SendData(y & 0xff);
    SendData((y + l - 1) >> 8);        
    SendData((y + l - 1) & 0xff);
    SendData(0x01);         // Gates scan both inside and outside of the partial window. (default) 
    DelayMs(2);
    SendCommand(DATA_START_TRANSMISSION_2);
    if (buffer_red != NULL) {
        for(int i = 0; i < w  / 8 * l; i++) {
            SendData(buffer_red[i]);  
        }  
    }
    DelayMs(2);
    SendCommand(PARTIAL_OUT);  
}

/**
 * @brief: refresh and displays the frame
 */
void Epd::DisplayFrame(const unsigned char* frame_black, const unsigned char* frame_red) {
    if (frame_black != NULL) {
        SendCommand(DATA_START_TRANSMISSION_1);
        DelayMs(2);
        for (int i = 0; i < this->width / 8 * this->height; i++) {
            SendData(pgm_read_byte(&frame_black[i]));
        }
        DelayMs(2);
    }
    if (frame_red != NULL) {
        SendCommand(DATA_START_TRANSMISSION_2);
        DelayMs(2);
        for (int i = 0; i < this->width / 8 * this->height; i++) {
            SendData(pgm_read_byte(&frame_red[i]));
        }
        DelayMs(2);
    }
    SendCommand(DISPLAY_REFRESH);
    WaitUntilIdle();
}

/**
 * @brief: clear the frame data from the SRAM, this won't refresh the display
 */
void Epd::ClearFrame(void) {
    SendCommand(DATA_START_TRANSMISSION_1);           
    DelayMs(2);
    for(int i = 0; i < width / 8 * height; i++) {
        SendData(0xFF);  
    }  
    DelayMs(2);
    SendCommand(DATA_START_TRANSMISSION_2);           
    DelayMs(2);
    for(int i = 0; i < width / 8 * height; i++) {
        SendData(0xFF);  
    }  
    DelayMs(2);
}

/**
 * @brief: This displays the frame data from SRAM
 */
void Epd::DisplayFrame(void) {
    SendCommand(DISPLAY_REFRESH); 
    DelayMs(100);
    WaitUntilIdle();
}

/**
 * @brief: After this command is transmitted, the chip would enter the deep-sleep mode to save power. 
 *         The deep sleep mode would return to standby by hardware reset. The only one parameter is a 
 *         check code, the command would be executed if check code = 0xA5. 
 *         You can use Epd::Reset() to awaken and use Epd::Init() to initialize.
 */
void Epd::Sleep() {
    SendCommand(VCOM_AND_DATA_INTERVAL_SETTING);
    SendData(0xF7);     // border floating
    SendCommand(POWER_OFF);
    WaitUntilIdle();
    SendCommand(DEEP_SLEEP);
    SendData(0xA5);     // check code
}


/* END OF FILE */