Yuheng Huo
/
hyh_copy_copy
test
Diff: N5110/N5110.cpp
- Revision:
- 1:48b0bf0bcda8
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/N5110/N5110.cpp Fri May 15 12:32:47 2020 +0000 @@ -0,0 +1,507 @@ +#include "mbed.h" +#include "N5110.h" + +// overloaded constructor includes power pin - LCD Vcc connected to GPIO pin +// this constructor works fine with LPC1768 - enough current sourced from GPIO +// to power LCD. Doesn't work well with K64F. +N5110::N5110(PinName const pwrPin, + PinName const scePin, + PinName const rstPin, + PinName const dcPin, + PinName const mosiPin, + PinName const sclkPin, + PinName const ledPin) + : + _spi(new SPI(mosiPin,NC,sclkPin)), // create new SPI instance and initialise + _led(new PwmOut(ledPin)), + _pwr(new DigitalOut(pwrPin)), + _sce(new DigitalOut(scePin)), + _rst(new DigitalOut(rstPin)), + _dc(new DigitalOut(dcPin)) +{} + +// overloaded constructor does not include power pin - LCD Vcc must be tied to +3V3 +// Best to use this with K64F as the GPIO hasn't sufficient output current to reliably +// drive the LCD. +N5110::N5110(PinName const scePin, + PinName const rstPin, + PinName const dcPin, + PinName const mosiPin, + PinName const sclkPin, + PinName const ledPin) + : + _spi(new SPI(mosiPin,NC,sclkPin)), // create new SPI instance and initialise + _led(new PwmOut(ledPin)), + _pwr(NULL), // pwr not needed so null it to be safe + _sce(new DigitalOut(scePin)), + _rst(new DigitalOut(rstPin)), + _dc(new DigitalOut(dcPin)) +{} + +N5110::~N5110() +{ + delete _spi; + + if(_pwr) { + delete _pwr; + } + + delete _led; + delete _sce; + delete _rst; + delete _dc; +} + +// initialise function - powers up and sends the initialisation commands +void N5110::init() +{ + turnOn(); // power up + reset(); // reset LCD - must be done within 100 ms + initSPI(); + + setContrast(0.55); // this may need tuning (say 0.4 to 0.6) + setBias(3); // datasheet - 48:1 mux - don't mess with if you don't know what you're doing! (0 to 7) + setTempCoefficient(0); // datasheet - may need increasing (range 0 to 3) at very low temperatures + normalMode(); // normal video mode by default + + clearRAM(); // RAM is undefined at power-up so clear to be sure + clear(); // clear buffer + setBrightness(0.5); +} + +// sets normal video mode (black on white) +void N5110::normalMode() +{ + sendCommand(0b00100000); // basic instruction + sendCommand(0b00001100); // normal video mode- datasheet +} + +// sets normal video mode (white on black) +void N5110::inverseMode() +{ + sendCommand(0b00100000); // basic instruction + sendCommand(0b00001101); // inverse video mode - datasheet +} + +// function to power up the LCD and backlight - only works when using GPIO to power +void N5110::turnOn() +{ + if (_pwr != NULL) { + _pwr->write(1); // apply power + } +} + +// function to power down LCD +void N5110::turnOff() +{ + clear(); // clear buffer + refresh(); + setBrightness(0.0); // turn backlight off + clearRAM(); // clear RAM to ensure specified current consumption + // send command to ensure we are in basic mode + + sendCommand(0b00100000); // basic mode + sendCommand(0b00001000); // clear display + sendCommand(0b00100001); // extended mode + sendCommand(0b00100100); // power down + + // if we are powering the LCD using the GPIO then make it low to turn off + if (_pwr != NULL) { + wait_ms(10); // small delay and then turn off the power pin + _pwr->write(0); // turn off power + } + +} + +// function to change LED backlight brightness +void N5110::setBrightness(float brightness) +{ + // check whether brightness is within range + if (brightness < 0.0f) + brightness = 0.0f; + if (brightness > 1.0f) + brightness = 1.0f; + // set PWM duty cycle + _led->write(brightness); +} + +void N5110::setContrast(float contrast) { + + // enforce limits + if (contrast > 1.0f) + contrast = 1.0f; + else if (contrast < 0.0f) + contrast = 0.0; + + // convert to char in range 0 to 127 (i.e. 6 bits) + char ic = char(contrast*127.0f); + + sendCommand(0b00100001); // extended instruction set + sendCommand(0b10000000 | ic); // set Vop (which controls contrast) + sendCommand(0b00100000); // back to basic instruction set +} + +void N5110::setTempCoefficient(char tc) { + + // enforce limits + if (tc>3) { + tc=3; + } + + // temperature coefficient may need increasing at low temperatures + + sendCommand(0b00100001); // extended instruction set + sendCommand(0b00000100 | tc); + sendCommand(0b00100000); // back to basic instruction set +} + +void N5110::setBias(char bias) { + + // from data sheet + // bias mux rate + // 0 1:100 + // 1 1:80 + // 2 1:65 + // 3 1:48 (default) + // 4 1:40/1:34 + // 5 1:24 + // 6 1:18/1:16 + // 7 1:10/1:9/1:8 + + // enforce limits + if (bias>7) { + bias=7; + } + + sendCommand(0b00100001); // extended mode instruction + sendCommand(0b00010000 | bias); + sendCommand(0b00100000); // end of extended mode instruction +} + +// 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 +} + +// send a command to the display +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) +} + +// send data to the display at the current XY address +// dc is set to 1 (i.e. data) after sending a command and so should +// be the default mode. +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() +{ + _sce->write(0); //set CE low to begin frame + for(int i = 0; i < WIDTH * HEIGHT; i++) { // 48 x 84 bits = 504 bytes + _spi->write(0x00); // send 0's + } + _sce->write(1); // set CE high to end frame +} + +// function to set the XY address in RAM for subsequenct data write +void N5110::setXYAddress(unsigned int const x, + unsigned int const y) +{ + if (x<WIDTH && y<HEIGHT) { // check within range + sendCommand(0b00100000); // basic instruction + sendCommand(0b10000000 | x); // send addresses to display with relevant mask + sendCommand(0b01000000 | y); + } +} + +// These functions are used to set, clear and get the value of pixels in the display +// Pixels are addressed in the range of 0 to 47 (y) and 0 to 83 (x). The refresh() +// function must be called after set and clear in order to update the display +void N5110::setPixel(unsigned int const x, + unsigned int const y, + bool const state) +{ + if (x<WIDTH && y<HEIGHT) { // check within range + // calculate bank and shift 1 to required position in the data byte + if(state) buffer[x][y/8] |= (1 << y%8); + else buffer[x][y/8] &= ~(1 << y%8); + + } +} + +void N5110::setScreen(unsigned char data[84][6]){ + for(int i=0; i<84; i++){ + for(int j=0; j<6; j++){ + buffer[i][j] &= (unsigned char)data[i][j]; + buffer[i][j] |= (unsigned char)data[i][j]; + } + } +} + +void N5110::clearPixel(unsigned int const x, + unsigned int const y) +{ + if (x<WIDTH && y<HEIGHT) { // check within range + // calculate bank and shift 1 to required position (using bit clear) + buffer[x][y/8] &= ~(1 << y%8); + } +} + +int N5110::getPixel(unsigned int const x, + unsigned int const y) const +{ + if (x<WIDTH && y<HEIGHT) { // check within range + // return relevant bank and mask required bit + + int pixel = (int) buffer[x][y/8] & (1 << y%8); + + if (pixel) + return 1; + else + return 0; + } + + return 0; + +} + +// function to refresh the display +void N5110::refresh() +{ + setXYAddress(0,0); // important to set address back to 0,0 before refreshing display + // address auto increments after printing string, so buffer[0][0] will not coincide + // with top-left pixel after priting string + + _sce->write(0); //set CE low to begin frame + + for(int j = 0; j < BANKS; j++) { // be careful to use correct order (j,i) for horizontal addressing + for(int i = 0; i < WIDTH; i++) { + _spi->write(buffer[i][j]); // send buffer + } + } + _sce->write(1); // set CE high to end frame + +} + +// fills the buffer with random bytes. Can be used to test the display. +// The rand() function isn't seeded so it probably creates the same pattern everytime +void N5110::randomiseBuffer() +{ + int i,j; + for(j = 0; j < BANKS; j++) { // be careful to use correct order (j,i) for horizontal addressing + for(i = 0; i < WIDTH; i++) { + buffer[i][j] = rand()%256; // generate random byte + } + } + +} + +// function to print 5x7 font +void N5110::printChar(char const c, + unsigned int const x, + unsigned int const y) +{ + if (y<BANKS) { // check if printing in range of y banks + + for (int i = 0; i < 5 ; i++ ) { + int pixel_x = x+i; + if (pixel_x > WIDTH-1) // ensure pixel isn't outside the buffer size (0 - 83) + break; + buffer[pixel_x][y] = font5x7[(c - 32)*5 + i]; + // array is offset by 32 relative to ASCII, each character is 5 pixels wide + } + + } +} + +// function to print string at specified position +void N5110::printString(const char *str, + unsigned int const x, + unsigned int const y) +{ + if (y<BANKS) { // check if printing in range of y banks + + int n = 0 ; // counter for number of characters in string + // loop through string and print character + while(*str) { + + // writes the character bitmap data to the buffer, so that + // text and pixels can be displayed at the same time + for (int i = 0; i < 5 ; i++ ) { + int pixel_x = x+i+n*6; + if (pixel_x > WIDTH-1) // ensure pixel isn't outside the buffer size (0 - 83) + break; + buffer[pixel_x][y] = font5x7[(*str - 32)*5 + i]; + } + str++; // go to next character in string + n++; // increment index + } + } +} + +// function to clear the screen buffer +void N5110::clear() +{ + memset(buffer,0,sizeof(buffer)); +} + +// function to plot array on display +void N5110::plotArray(float const array[]) +{ + for (int i=0; i<WIDTH; i++) { // loop through array + // elements are normalised from 0.0 to 1.0, so multiply + // by 47 to convert to pixel range, and subtract from 47 + // since top-left is 0,0 in the display geometry + setPixel(i,47 - int(array[i]*47.0f),true); + } + +} + +// function to draw circle +void N5110:: drawCircle(unsigned int const x0, + unsigned int const y0, + unsigned int const radius, + FillType const fill) +{ + // from http://en.wikipedia.org/wiki/Midpoint_circle_algorithm + int x = radius; + int y = 0; + int radiusError = 1-x; + + while(x >= y) { + + // if transparent, just draw outline + if (fill == FILL_TRANSPARENT) { + setPixel( x + x0, y + y0,true); + setPixel(-x + x0, y + y0,true); + setPixel( y + x0, x + y0,true); + setPixel(-y + x0, x + y0,true); + setPixel(-y + x0, -x + y0,true); + setPixel( y + x0, -x + y0,true); + setPixel( x + x0, -y + y0,true); + setPixel(-x + x0, -y + y0,true); + } else { // drawing filled circle, so draw lines between points at same y value + + int type = (fill==FILL_BLACK) ? 1:0; // black or white fill + + drawLine(x+x0,y+y0,-x+x0,y+y0,type); + drawLine(y+x0,x+y0,-y+x0,x+y0,type); + drawLine(y+x0,-x+y0,-y+x0,-x+y0,type); + drawLine(x+x0,-y+y0,-x+x0,-y+y0,type); + } + + y++; + if (radiusError<0) { + radiusError += 2 * y + 1; + } else { + x--; + radiusError += 2 * (y - x) + 1; + } + } + +} + +void N5110::drawLine(unsigned int const x0, + unsigned int const y0, + unsigned int const x1, + unsigned int const y1, + unsigned int const type) +{ + // Note that the ranges can be negative so we have to turn the input values + // into signed integers first + int const y_range = static_cast<int>(y1) - static_cast<int>(y0); + int const x_range = static_cast<int>(x1) - static_cast<int>(x0); + + // if dotted line, set step to 2, else step is 1 + unsigned int const step = (type==2) ? 2:1; + + // make sure we loop over the largest range to get the most pixels on the display + // for instance, if drawing a vertical line (x_range = 0), we need to loop down the y pixels + // or else we'll only end up with 1 pixel in the x column + if ( abs(x_range) > abs(y_range) ) { + + // ensure we loop from smallest to largest or else for-loop won't run as expected + unsigned int const start = x_range > 0 ? x0:x1; + unsigned int const stop = x_range > 0 ? x1:x0; + + // loop between x pixels + for (unsigned int x = start; x<= stop ; x+=step) { + // do linear interpolation + int const dx = static_cast<int>(x)-static_cast<int>(x0); + unsigned int const y = y0 + y_range * dx / x_range; + + // If the line type is '0', this will clear the pixel + // If it is '1' or '2', the pixel will be set + setPixel(x,y, type); + } + } else { + + // ensure we loop from smallest to largest or else for-loop won't run as expected + unsigned int const start = y_range > 0 ? y0:y1; + unsigned int const stop = y_range > 0 ? y1:y0; + + for (unsigned int y = start; y<= stop ; y+=step) { + // do linear interpolation + int const dy = static_cast<int>(y)-static_cast<int>(y0); + unsigned int const x = x0 + x_range * dy / y_range; + + // If the line type is '0', this will clear the pixel + // If it is '1' or '2', the pixel will be set + setPixel(x,y, type); + } + } + +} + +void N5110::drawRect(unsigned int const x0, + unsigned int const y0, + unsigned int const width, + unsigned int const height, + FillType const fill) +{ + if (fill == FILL_TRANSPARENT) { // transparent, just outline + drawLine(x0,y0,x0+(width-1),y0,1); // top + drawLine(x0,y0+(height-1),x0+(width-1),y0+(height-1),1); // bottom + drawLine(x0,y0,x0,y0+(height-1),1); // left + drawLine(x0+(width-1),y0,x0+(width-1),y0+(height-1),1); // right + } else { // filled rectangle + int type = (fill==FILL_BLACK) ? 1:0; // black or white fill + for (int y = y0; y<y0+height; y++) { // loop through rows of rectangle + drawLine(x0,y,x0+(width-1),y,type); // draw line across screen + } + } +} + +void N5110::drawSprite(int x0, + int y0, + int nrows, + int ncols, + int *sprite) +{ + for (int i = 0; i < nrows; i++) { + for (int j = 0 ; j < ncols ; j++) { + + int pixel = *((sprite+i*ncols)+j); + setPixel(x0+j,y0+i, pixel); + } + } +}