Tamas Titusz Ban
Template for the ELEC1620 End of year exam
Diff: N5110/N5110.cpp
- Revision:
- 0:54721f063ac8
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/N5110/N5110.cpp Fri Mar 22 13:11:07 2019 +0000
@@ -0,0 +1,542 @@
+#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);
+ _stream->writeMessage(0x1, 0x00);
+ _stream->sendMessages();
+}
+
+// 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
+ }
+ _stream->writeMessage(0x2, 0x00);
+ _stream->sendMessages();
+}
+
+// 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);
+
+ _stream->writeMessage(0x3, (unsigned int)(brightness * 1000000));
+ _stream->sendMessages();
+}
+
+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);
+
+ _stream->writeMessage(0x4, 0x00);
+ _stream->sendMessages();
+}
+
+// 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);
+
+ _stream->writeMessage(0x5, ((x & 0x7F) << 8) | ((y & 0x7F) << 1) | (state & 0x1));
+ }
+}
+
+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);
+ _stream->writeMessage(0x6, ((x & 0x7F) << 7) | (y & 0x7F));
+ }
+}
+
+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
+
+ _stream->writeMessage(0x7, 0x00);
+ _stream->sendMessages();
+
+}
+
+// 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
+ }
+ _stream->writeMessage(0x8, ((x & 0x7F) << 15) | ((y & 0x7F) << 8) | c);
+
+ }
+}
+
+// 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];
+ }
+
+ _stream->writeMessage(0x8, (((x + n * 6) & 0x7F) << 15) | ((y & 0x7F) << 8) | *str);
+
+
+ str++; // go to next character in string
+ n++; // increment index
+ }
+ }
+}
+
+// function to clear the screen buffer
+void N5110::clear()
+{
+ memset(buffer,0,sizeof(buffer));
+ _stream->writeMessage(0x9, 0x00);
+}
+
+// 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;
+ _stream->lock();
+ 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;
+ }
+ }
+ _stream->unlock();
+ _stream->writeMessage(0xa,
+ ((x0 & 0x7F) << 16) |
+ ((y0 & 0x7F) << 9) |
+ ((radius & 0x7F) << 2) |
+ (fill==FILL_TRANSPARENT ? 0x00 : (fill==FILL_BLACK ? 0x01 : 0x02)));
+
+
+}
+
+void N5110::drawLine(unsigned int const x0,
+ unsigned int const y0,
+ unsigned int const x1,
+ unsigned int const y1,
+ unsigned int const type)
+{
+ _stream->lock();
+ // 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);
+ }
+ }
+ _stream->unlock();
+ _stream->writeMessage(0xb,
+ ((x0 & 0x7F) << 23) |
+ ((y0 & 0x7F) << 16) |
+ ((x1 & 0x7F) << 9) |
+ ((y1 & 0x7F) << 2) |
+ (type & 0x3));
+
+}
+
+void N5110::drawRect(unsigned int const x0,
+ unsigned int const y0,
+ unsigned int const width,
+ unsigned int const height,
+ FillType const fill)
+{
+ _stream->lock();
+ 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
+ }
+ }
+ _stream->unlock();
+ _stream->writeMessage(0xc,
+ ((x0 & 0x7F) << 23) |
+ ((y0 & 0x7F) << 16) |
+ ((width & 0x7F) << 9) |
+ ((height & 0x7F) << 2) |
+ (fill==FILL_TRANSPARENT ? 0x00 : (fill==FILL_BLACK ? 0x01 : 0x02)));
+}
+
+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);
+ }
+ }
+}
+