Yang Junyao 201090191
N5110.cpp
- Committer:
- eencae
- Date:
- 2014-01-26
- Revision:
- 1:df68f34cd32d
- Parent:
- 0:d563e74f0ae9
- Child:
- 2:e93021cfb0a9
File content as of revision 1:df68f34cd32d:
#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; } } }