File content as of revision 2:e93021cfb0a9:

#include "mbed.h"
#include "N5110.h"


N5110::N5110(PinName pwrPin, PinName scePin, PinName rstPin, PinName dcPin, PinName mosiPin, PinName sclkPin, PinName ledPin)
{
    
    spi = new SPI(mosiPin,NC,sclkPin); // create new SPI instance and initialise
    initSPI();    
    
    led = new PwmOut(ledPin);
    pwr = new DigitalOut(pwrPin);
    sce = new DigitalOut(scePin);
    rst = new DigitalOut(rstPin);
    dc = new DigitalOut(dcPin);

}


void N5110::init()
{
    turnOn();    // power up
    reset();     // reset LCD - must be done within 100 ms

    // function set - extended
    sendCommand(0x20 | CMD_FS_ACTIVE_MODE | CMD_FS_HORIZONTAL_MODE | CMD_FS_EXTENDED_MODE);

    sendCommand(CMD_VOP_7V38);    // operating voltage - these values are from Chris Yan's Library
    sendCommand(CMD_TC_TEMP_2);   // temperature control
    sendCommand(CMD_BI_MUX_48);   // bias

    // function set - basic
    sendCommand(0x20 | CMD_FS_ACTIVE_MODE | CMD_FS_HORIZONTAL_MODE | CMD_FS_BASIC_MODE);
    normalMode();  // normal video mode by default
    sendCommand(CMD_DC_NORMAL_MODE);  // black on white
    //sendCommand(CMD_DC_INVERT_VIDEO);  // white on black

    // RAM is undefined at power-up so clear
    clearRAM();

}
 
// sets normal video mode (black on white) 
void N5110::normalMode() {
     sendCommand(CMD_DC_NORMAL_MODE);  
   
}

// sets normal video mode (white on black) 
void N5110::inverseMode() {
    sendCommand(CMD_DC_INVERT_VIDEO); 
}

// function to power up the LCD and backlight
void N5110::turnOn()
{
    // set brightness of LED - 0.0 to 1.0 - default is 50%
    setBrightness(0.5);
    pwr->write(1);  // apply power
}

// function to power down LCD
void N5110::turnOff()
{

    setBrightness(0.0);  // turn backlight off
    clearRAM();   // clear RAM to ensure specified current consumption
    sendCommand(0x20 | CMD_FS_ACTIVE_MODE | CMD_FS_HORIZONTAL_MODE | CMD_FS_BASIC_MODE);
    sendCommand(CMD_DC_CLEAR_DISPLAY);
    sendCommand(0x20 | CMD_FS_POWER_DOWN_MODE | CMD_FS_HORIZONTAL_MODE | CMD_FS_EXTENDED_MODE);
    pwr->write(0);

}

// function to change LED backlight brightness
void N5110::setBrightness(float brightness)
{
    // check whether brightness is within range
    if (brightness < 0.0)
        brightness = 0.0;
    if (brightness > 1.0)
        brightness = 1.0;
    // set PWM duty cycle
    led->write(brightness);
}


// pulse the active low reset line
void N5110::reset()
{
    rst->write(0);  // reset the LCD
    rst->write(1);
}

// function to initialise SPI peripheral
void N5110::initSPI()
{
    spi->format(8,1);    // 8 bits, Mode 1 - polarity 0, phase 1 - base value of clock is 0, data captured on falling edge/propagated on rising edge
    spi->frequency(4000000);  // maximum of screen is 4 MHz
}

void N5110::sendCommand(unsigned char command)
{
    dc->write(0);  // set DC low for command
    sce->write(0); // set CE low to begin frame
    spi->write(command);  // send command
    dc->write(1);  // turn back to data by default
    sce->write(1); // set CE high to end frame (expected for transmission of single byte)

}

void N5110::sendData(unsigned char data)
{
    sce->write(0);   // set CE low to begin frame
    spi->write(data);
    sce->write(1);  // set CE high to end frame (expected for transmission of single byte)
}

// this function writes 0 to the 504 bytes to clear the RAM
void N5110::clearRAM()
{
    int i;
    sce->write(0);  //set CE low to begin frame
    for(i = 0; i < 504; i++) { // 48 x 84 bits = 504 bytes
        spi->write(0x00);  // send 0's
    }
    sce->write(1); // set CE high to end frame

}

void N5110::setXYAddress(int x, int y)
{

    // check whether address is in range
    if (x > 83)
        x=83;
    if (y > 5)
        y=5;

    sendCommand(0x80 | x);
    sendCommand(0x40 | y);
}

void N5110::setPixel(int x, int y)
{
    // calculate bank and shift 1 to required position
    buffer[x][y/8] |= (1 << y%8);
}

void N5110::clearPixel(int x, int y)
{
    // calculate bank and shift 1 to required position (using bit clear)
    buffer[x][y/8] &= ~(1 << y%8);
}

unsigned char N5110::getPixel(int x, int y)
{
    // return relevant bank and mask required bit
    return buffer[x][y/8] & (1 << y%8);

}

void N5110::refreshDisplay()
{

    int i,j;
    sce->write(0);  //set CE low to begin frame

    for(j = 0; j < 6; j++) {  // be careful to use correct order (j,i) for horizontal addressing
        for(i = 0; i < 84; i++) {
            spi->write(buffer[i][j]);  // send buffer
        }
    }
    sce->write(1); // set CE high to end frame

}

void N5110::randomiseBuffer()
{

    int i,j;

    for(j = 0; j < 6; j++) {  // be careful to use correct order (j,i) for horizontal addressing
        for(i = 0; i < 84; i++) {
            buffer[i][j] = rand()%256;  // generate random byte
        }
    }

}

// function to print 5x7 font
void N5110::printChar(char c)
{

    // loop through 5 columns
    for (int j = 0; j < 5 ; j++ ) {
        sendData(font5x7[(c - 32)*5 + j]);
        // array is offset by 32 relative to ASCII, each character is 5 pixels wide
    }
    
    sendData(0); // send an empty byte to introduce space between characters

}

// function to print string at specified position
void N5110::printString(const char * str,int x,int y)
{
    int n = 0 ; // counter for number of characters in string
    // loop through string and print character
    while(*str) {

        setXYAddress(x+6*n,y);  // leave 1 pixel (6 = 5 + 1) between each character
        printChar(*str);
        str++;  // go to next character in string
        n++;    // increment index
    }

}

void N5110::clear()
{
    clearBuffer();
    refreshDisplay();
}

void N5110::clearBuffer()
{
    int i,j;
    for (i=0; i<84; i++) {
        for (j=0; j<6; j++) {
            buffer[i][j]=0;
        }
    }
}