James Heavey
FINAL VERSION
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N5110.cpp
00001 #include "mbed.h" 00002 #include "N5110.h" 00003 00004 // overloaded constructor includes power pin - LCD Vcc connected to GPIO pin 00005 // this constructor works fine with LPC1768 - enough current sourced from GPIO 00006 // to power LCD. Doesn't work well with K64F. 00007 N5110::N5110(PinName const pwrPin, 00008 PinName const scePin, 00009 PinName const rstPin, 00010 PinName const dcPin, 00011 PinName const mosiPin, 00012 PinName const sclkPin, 00013 PinName const ledPin) 00014 : 00015 _spi(new SPI(mosiPin,NC,sclkPin)), // create new SPI instance and initialise 00016 _led(new PwmOut(ledPin)), 00017 _pwr(new DigitalOut(pwrPin)), 00018 _sce(new DigitalOut(scePin)), 00019 _rst(new DigitalOut(rstPin)), 00020 _dc(new DigitalOut(dcPin)) 00021 {} 00022 00023 // overloaded constructor does not include power pin - LCD Vcc must be tied to +3V3 00024 // Best to use this with K64F as the GPIO hasn't sufficient output current to reliably 00025 // drive the LCD. 00026 N5110::N5110(PinName const scePin, 00027 PinName const rstPin, 00028 PinName const dcPin, 00029 PinName const mosiPin, 00030 PinName const sclkPin, 00031 PinName const ledPin) 00032 : 00033 _spi(new SPI(mosiPin,NC,sclkPin)), // create new SPI instance and initialise 00034 _led(new PwmOut(ledPin)), 00035 _pwr(NULL), // pwr not needed so null it to be safe 00036 _sce(new DigitalOut(scePin)), 00037 _rst(new DigitalOut(rstPin)), 00038 _dc(new DigitalOut(dcPin)) 00039 {} 00040 00041 N5110::~N5110() 00042 { 00043 delete _spi; 00044 00045 if(_pwr) { 00046 delete _pwr; 00047 } 00048 00049 delete _led; 00050 delete _sce; 00051 delete _rst; 00052 delete _dc; 00053 } 00054 00055 // initialise function - powers up and sends the initialisation commands 00056 void N5110::init() 00057 { 00058 turnOn(); // power up 00059 reset(); // reset LCD - must be done within 100 ms 00060 initSPI(); 00061 00062 setContrast(0.55); // this may need tuning (say 0.4 to 0.6) 00063 setBias(3); // datasheet - 48:1 mux - don't mess with if you don't know what you're doing! (0 to 7) 00064 setTempCoefficient(0); // datasheet - may need increasing (range 0 to 3) at very low temperatures 00065 normalMode(); // normal video mode by default 00066 00067 clearRAM(); // RAM is undefined at power-up so clear to be sure 00068 clear(); // clear buffer 00069 setBrightness(0.5); 00070 } 00071 00072 // sets normal video mode (black on white) 00073 void N5110::normalMode() 00074 { 00075 sendCommand(0b00100000); // basic instruction 00076 sendCommand(0b00001100); // normal video mode- datasheet 00077 } 00078 00079 // sets normal video mode (white on black) 00080 void N5110::inverseMode() 00081 { 00082 sendCommand(0b00100000); // basic instruction 00083 sendCommand(0b00001101); // inverse video mode - datasheet 00084 } 00085 00086 // function to power up the LCD and backlight - only works when using GPIO to power 00087 void N5110::turnOn() 00088 { 00089 if (_pwr != NULL) { 00090 _pwr->write(1); // apply power 00091 } 00092 } 00093 00094 // function to power down LCD 00095 void N5110::turnOff() 00096 { 00097 clear(); // clear buffer 00098 refresh(); 00099 setBrightness(0.0); // turn backlight off 00100 clearRAM(); // clear RAM to ensure specified current consumption 00101 // send command to ensure we are in basic mode 00102 00103 sendCommand(0b00100000); // basic mode 00104 sendCommand(0b00001000); // clear display 00105 sendCommand(0b00100001); // extended mode 00106 sendCommand(0b00100100); // power down 00107 00108 // if we are powering the LCD using the GPIO then make it low to turn off 00109 if (_pwr != NULL) { 00110 wait_ms(10); // small delay and then turn off the power pin 00111 _pwr->write(0); // turn off power 00112 } 00113 00114 } 00115 00116 // function to change LED backlight brightness 00117 void N5110::setBrightness(float brightness) 00118 { 00119 // check whether brightness is within range 00120 if (brightness < 0.0f) 00121 brightness = 0.0f; 00122 if (brightness > 1.0f) 00123 brightness = 1.0f; 00124 // set PWM duty cycle 00125 _led->write(brightness); 00126 } 00127 00128 void N5110::setContrast(float contrast) { 00129 00130 // enforce limits 00131 if (contrast > 1.0f) 00132 contrast = 1.0f; 00133 else if (contrast < 0.0f) 00134 contrast = 0.0; 00135 00136 // convert to char in range 0 to 127 (i.e. 6 bits) 00137 char ic = char(contrast*127.0f); 00138 00139 sendCommand(0b00100001); // extended instruction set 00140 sendCommand(0b10000000 | ic); // set Vop (which controls contrast) 00141 sendCommand(0b00100000); // back to basic instruction set 00142 } 00143 00144 void N5110::setTempCoefficient(char tc) { 00145 00146 // enforce limits 00147 if (tc>3) { 00148 tc=3; 00149 } 00150 00151 // temperature coefficient may need increasing at low temperatures 00152 00153 sendCommand(0b00100001); // extended instruction set 00154 sendCommand(0b00000100 | tc); 00155 sendCommand(0b00100000); // back to basic instruction set 00156 } 00157 00158 void N5110::setBias(char bias) { 00159 00160 // from data sheet 00161 // bias mux rate 00162 // 0 1:100 00163 // 1 1:80 00164 // 2 1:65 00165 // 3 1:48 (default) 00166 // 4 1:40/1:34 00167 // 5 1:24 00168 // 6 1:18/1:16 00169 // 7 1:10/1:9/1:8 00170 00171 // enforce limits 00172 if (bias>7) { 00173 bias=7; 00174 } 00175 00176 sendCommand(0b00100001); // extended mode instruction 00177 sendCommand(0b00010000 | bias); 00178 sendCommand(0b00100000); // end of extended mode instruction 00179 } 00180 00181 // pulse the active low reset line 00182 void N5110::reset() 00183 { 00184 _rst->write(0); // reset the LCD 00185 _rst->write(1); 00186 } 00187 00188 // function to initialise SPI peripheral 00189 void N5110::initSPI() 00190 { 00191 _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 00192 _spi->frequency(4000000); // maximum of screen is 4 MHz 00193 } 00194 00195 // send a command to the display 00196 void N5110::sendCommand(unsigned char command) 00197 { 00198 _dc->write(0); // set DC low for command 00199 _sce->write(0); // set CE low to begin frame 00200 _spi->write(command); // send command 00201 _dc->write(1); // turn back to data by default 00202 _sce->write(1); // set CE high to end frame (expected for transmission of single byte) 00203 } 00204 00205 // send data to the display at the current XY address 00206 // dc is set to 1 (i.e. data) after sending a command and so should 00207 // be the default mode. 00208 void N5110::sendData(unsigned char data) 00209 { 00210 _sce->write(0); // set CE low to begin frame 00211 _spi->write(data); 00212 _sce->write(1); // set CE high to end frame (expected for transmission of single byte) 00213 } 00214 00215 // this function writes 0 to the 504 bytes to clear the RAM 00216 void N5110::clearRAM() 00217 { 00218 _sce->write(0); //set CE low to begin frame 00219 for(int i = 0; i < WIDTH * HEIGHT; i++) { // 48 x 84 bits = 504 bytes 00220 _spi->write(0x00); // send 0's 00221 } 00222 _sce->write(1); // set CE high to end frame 00223 } 00224 00225 // function to set the XY address in RAM for subsequenct data write 00226 void N5110::setXYAddress(unsigned int const x, 00227 unsigned int const y) 00228 { 00229 if (x<WIDTH && y<HEIGHT) { // check within range 00230 sendCommand(0b00100000); // basic instruction 00231 sendCommand(0b10000000 | x); // send addresses to display with relevant mask 00232 sendCommand(0b01000000 | y); 00233 } 00234 } 00235 00236 // These functions are used to set, clear and get the value of pixels in the display 00237 // Pixels are addressed in the range of 0 to 47 (y) and 0 to 83 (x). The refresh() 00238 // function must be called after set and clear in order to update the display 00239 void N5110::setPixel(unsigned int const x, 00240 unsigned int const y, 00241 bool const state) 00242 { 00243 if (x<WIDTH && y<HEIGHT) { // check within range 00244 // calculate bank and shift 1 to required position in the data byte 00245 if(state) buffer[x][y/8] |= (1 << y%8); 00246 else buffer[x][y/8] &= ~(1 << y%8); 00247 } 00248 } 00249 00250 void N5110::clearPixel(unsigned int const x, 00251 unsigned int const y) 00252 { 00253 if (x<WIDTH && y<HEIGHT) { // check within range 00254 // calculate bank and shift 1 to required position (using bit clear) 00255 buffer[x][y/8] &= ~(1 << y%8); 00256 } 00257 } 00258 00259 int N5110::getPixel(unsigned int const x, 00260 unsigned int const y) const 00261 { 00262 if (x<WIDTH && y<HEIGHT) { // check within range 00263 // return relevant bank and mask required bit 00264 00265 int pixel = (int) buffer[x][y/8] & (1 << y%8); 00266 00267 if (pixel) 00268 return 1; 00269 else 00270 return 0; 00271 } 00272 00273 return 0; 00274 00275 } 00276 00277 // function to refresh the display 00278 void N5110::refresh() 00279 { 00280 setXYAddress(0,0); // important to set address back to 0,0 before refreshing display 00281 // address auto increments after printing string, so buffer[0][0] will not coincide 00282 // with top-left pixel after priting string 00283 00284 _sce->write(0); //set CE low to begin frame 00285 00286 for(int j = 0; j < BANKS; j++) { // be careful to use correct order (j,i) for horizontal addressing 00287 for(int i = 0; i < WIDTH; i++) { 00288 _spi->write(buffer[i][j]); // send buffer 00289 } 00290 } 00291 _sce->write(1); // set CE high to end frame 00292 00293 } 00294 00295 // fills the buffer with random bytes. Can be used to test the display. 00296 // The rand() function isn't seeded so it probably creates the same pattern everytime 00297 void N5110::randomiseBuffer() 00298 { 00299 int i,j; 00300 for(j = 0; j < BANKS; j++) { // be careful to use correct order (j,i) for horizontal addressing 00301 for(i = 0; i < WIDTH; i++) { 00302 buffer[i][j] = rand()%256; // generate random byte 00303 } 00304 } 00305 00306 } 00307 00308 // function to print 5x7 font 00309 void N5110::printChar(char const c, 00310 unsigned int const x, 00311 unsigned int const y) 00312 { 00313 if (y<BANKS) { // check if printing in range of y banks 00314 00315 for (int i = 0; i < 5 ; i++ ) { 00316 int pixel_x = x+i; 00317 if (pixel_x > WIDTH-1) // ensure pixel isn't outside the buffer size (0 - 83) 00318 break; 00319 buffer[pixel_x][y] = font5x7[(c - 32)*5 + i]; 00320 // array is offset by 32 relative to ASCII, each character is 5 pixels wide 00321 } 00322 00323 } 00324 } 00325 00326 // function to print string at specified position 00327 void N5110::printString(const char *str, 00328 unsigned int const x, 00329 unsigned int const y) 00330 { 00331 if (y<BANKS) { // check if printing in range of y banks 00332 00333 int n = 0 ; // counter for number of characters in string 00334 // loop through string and print character 00335 while(*str) { 00336 00337 // writes the character bitmap data to the buffer, so that 00338 // text and pixels can be displayed at the same time 00339 for (int i = 0; i < 5 ; i++ ) { 00340 int pixel_x = x+i+n*6; 00341 if (pixel_x > WIDTH-1) // ensure pixel isn't outside the buffer size (0 - 83) 00342 break; 00343 buffer[pixel_x][y] = font5x7[(*str - 32)*5 + i]; 00344 } 00345 str++; // go to next character in string 00346 n++; // increment index 00347 } 00348 } 00349 } 00350 00351 // function to clear the screen buffer 00352 void N5110::clear() 00353 { 00354 memset(buffer,0,sizeof(buffer)); 00355 } 00356 00357 // function to plot array on display 00358 void N5110::plotArray(float const array[]) 00359 { 00360 for (int i=0; i<WIDTH; i++) { // loop through array 00361 // elements are normalised from 0.0 to 1.0, so multiply 00362 // by 47 to convert to pixel range, and subtract from 47 00363 // since top-left is 0,0 in the display geometry 00364 setPixel(i,47 - int(array[i]*47.0f),true); 00365 } 00366 00367 } 00368 00369 // function to draw circle 00370 void N5110:: drawCircle(unsigned int const x0, 00371 unsigned int const y0, 00372 unsigned int const radius, 00373 FillType const fill) 00374 { 00375 // from http://en.wikipedia.org/wiki/Midpoint_circle_algorithm 00376 int x = radius; 00377 int y = 0; 00378 int radiusError = 1-x; 00379 00380 while(x >= y) { 00381 00382 // if transparent, just draw outline 00383 if (fill == FILL_TRANSPARENT) { 00384 setPixel( x + x0, y + y0,true); 00385 setPixel(-x + x0, y + y0,true); 00386 setPixel( y + x0, x + y0,true); 00387 setPixel(-y + x0, x + y0,true); 00388 setPixel(-y + x0, -x + y0,true); 00389 setPixel( y + x0, -x + y0,true); 00390 setPixel( x + x0, -y + y0,true); 00391 setPixel(-x + x0, -y + y0,true); 00392 } else { // drawing filled circle, so draw lines between points at same y value 00393 00394 int type = (fill==FILL_BLACK) ? 1:0; // black or white fill 00395 00396 drawLine(x+x0,y+y0,-x+x0,y+y0,type); 00397 drawLine(y+x0,x+y0,-y+x0,x+y0,type); 00398 drawLine(y+x0,-x+y0,-y+x0,-x+y0,type); 00399 drawLine(x+x0,-y+y0,-x+x0,-y+y0,type); 00400 } 00401 00402 y++; 00403 if (radiusError<0) { 00404 radiusError += 2 * y + 1; 00405 } else { 00406 x--; 00407 radiusError += 2 * (y - x) + 1; 00408 } 00409 } 00410 00411 } 00412 00413 void N5110::drawLine(unsigned int const x0, 00414 unsigned int const y0, 00415 unsigned int const x1, 00416 unsigned int const y1, 00417 unsigned int const type) 00418 { 00419 // Note that the ranges can be negative so we have to turn the input values 00420 // into signed integers first 00421 int const y_range = static_cast<int>(y1) - static_cast<int>(y0); 00422 int const x_range = static_cast<int>(x1) - static_cast<int>(x0); 00423 00424 // if dotted line, set step to 2, else step is 1 00425 unsigned int const step = (type==2) ? 2:1; 00426 00427 // make sure we loop over the largest range to get the most pixels on the display 00428 // for instance, if drawing a vertical line (x_range = 0), we need to loop down the y pixels 00429 // or else we'll only end up with 1 pixel in the x column 00430 if ( abs(x_range) > abs(y_range) ) { 00431 00432 // ensure we loop from smallest to largest or else for-loop won't run as expected 00433 unsigned int const start = x_range > 0 ? x0:x1; 00434 unsigned int const stop = x_range > 0 ? x1:x0; 00435 00436 // loop between x pixels 00437 for (unsigned int x = start; x<= stop ; x+=step) { 00438 // do linear interpolation 00439 int const dx = static_cast<int>(x)-static_cast<int>(x0); 00440 unsigned int const y = y0 + y_range * dx / x_range; 00441 00442 // If the line type is '0', this will clear the pixel 00443 // If it is '1' or '2', the pixel will be set 00444 setPixel(x,y, type); 00445 } 00446 } else { 00447 00448 // ensure we loop from smallest to largest or else for-loop won't run as expected 00449 unsigned int const start = y_range > 0 ? y0:y1; 00450 unsigned int const stop = y_range > 0 ? y1:y0; 00451 00452 for (unsigned int y = start; y<= stop ; y+=step) { 00453 // do linear interpolation 00454 int const dy = static_cast<int>(y)-static_cast<int>(y0); 00455 unsigned int const x = x0 + x_range * dy / y_range; 00456 00457 // If the line type is '0', this will clear the pixel 00458 // If it is '1' or '2', the pixel will be set 00459 setPixel(x,y, type); 00460 } 00461 } 00462 00463 } 00464 00465 void N5110::drawRect(unsigned int const x0, 00466 unsigned int const y0, 00467 unsigned int const width, 00468 unsigned int const height, 00469 FillType const fill) 00470 { 00471 if (fill == FILL_TRANSPARENT) { // transparent, just outline 00472 drawLine(x0,y0,x0+(width-1),y0,1); // top 00473 drawLine(x0,y0+(height-1),x0+(width-1),y0+(height-1),1); // bottom 00474 drawLine(x0,y0,x0,y0+(height-1),1); // left 00475 drawLine(x0+(width-1),y0,x0+(width-1),y0+(height-1),1); // right 00476 } else { // filled rectangle 00477 int type = (fill==FILL_BLACK) ? 1:0; // black or white fill 00478 for (int y = y0; y<y0+height; y++) { // loop through rows of rectangle 00479 drawLine(x0,y,x0+(width-1),y,type); // draw line across screen 00480 } 00481 } 00482 } 00483 00484 void N5110::drawSprite(int x0, 00485 int y0, 00486 int nrows, 00487 int ncols, 00488 int *sprite) 00489 { 00490 for (int i = 0; i < nrows; i++) { 00491 for (int j = 0 ; j < ncols ; j++) { 00492 00493 int pixel = *((sprite+i*ncols)+j); 00494 setPixel(x0+j,y0+i, pixel); 00495 } 00496 } 00497 }
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