Simple library for interfacing to Nokia 5110 LCD display (as found on the SparkFun website).
Fork of N5110 by
N5110.cpp
- Committer:
- qk2277
- Date:
- 2015-05-07
- Revision:
- 20:4145b7a59ef7
- Parent:
- 19:ba8addc061ea
File content as of revision 20:4145b7a59ef7:
/** @file N5110.cpp @brief Member functions implementations */ #include "N5110.h" #include "mbed.h" #include "BMP180.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(); // set up pins as required led = new PwmOut(ledPin); pwr = new DigitalOut(pwrPin); sce = new DigitalOut(scePin); rst = new DigitalOut(rstPin); dc = new DigitalOut(dcPin); } // initialise function - powers up and sends the initialisation commands void N5110::init() { turnOn(); // power up wait_ms(10); // small delay seems to prevent spurious pixels during mbed reset 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); // Don't completely understand these parameters - they seem to work as they are // Consult the datasheet if you need to change them 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 // 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 // send command to ensure we are in basic mode sendCommand(0x20 | CMD_FS_ACTIVE_MODE | CMD_FS_HORIZONTAL_MODE | CMD_FS_BASIC_MODE); // clear the display sendCommand(CMD_DC_CLEAR_DISPLAY); // enter the extended mode and power down sendCommand(0x20 | CMD_FS_POWER_DOWN_MODE | CMD_FS_HORIZONTAL_MODE | CMD_FS_EXTENDED_MODE); // small delay and then turn off the power pin wait_ms(10); 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 } // 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() { int i; sce->write(0); //set CE low to begin frame for(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(int x, int y) { if (x>=0 && x<WIDTH && y>=0 && y<HEIGHT) { // check within range sendCommand(0x80 | x); // send addresses to display with relevant mask sendCommand(0x40 | 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(int x, int y) { if (x>=0 && x<WIDTH && y>=0 && y<HEIGHT) { // check within range // calculate bank and shift 1 to required position in the data byte buffer[x][y/8] |= (1 << y%8); } } void N5110::clearPixel(int x, int y) { if (x>=0 && x<WIDTH && y>=0 && 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(int x, int y) { if (x>=0 && x<WIDTH && y>=0 && y<HEIGHT) { // check within range // return relevant bank and mask required bit return (int) buffer[x][y/8] & (1 << y%8); // note this does not necessarily return 1 - a non-zero number represents a pixel } else { return 0; } } // function to refresh the display void N5110::refresh() { int i,j; 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(j = 0; j < BANKS; j++) { // be careful to use correct order (j,i) for horizontal addressing for(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 c,int x,int y) { if (y>=0 && 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 } refresh(); // this sends the buffer to the display and sets address (cursor) back to 0,0 } } // function to print string at specified position void N5110::printString(const char * str,int x,int y) { if (y>=0 && 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 } refresh(); // this sends the buffer to the display and sets address (cursor) back to 0,0 } } // function to clear the screen void N5110::clear() { clearBuffer(); // clear the buffer then call the refresh function refresh(); } // function to clear the buffer void N5110::clearBuffer() { int i,j; for (i=0; i<WIDTH; i++) { // loop through the banks and set the buffer to 0 for (j=0; j<BANKS; j++) { buffer[i][j]=0; } } } // function to plot array on display void N5110::plotArray(float array[]) { int i; for (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]*47.0)); } refresh(); } // function to draw circle void N5110:: drawCircle(int x0,int y0,int radius,int 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 == 0) { setPixel( x + x0, y + y0); setPixel(-x + x0, y + y0); setPixel( y + x0, x + y0); setPixel(-y + x0, x + y0); setPixel(-y + x0, -x + y0); setPixel( y + x0, -x + y0); setPixel( x + x0, -y + y0); setPixel(-x + x0, -y + y0); } else { // drawing filled circle, so draw lines between points at same y value int type = (fill==1) ? 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(int x0,int y0,int x1,int y1,int type) { int y_range = y1-y0; // calc range of y and x int x_range = x1-x0; int start,stop,step; // if dotted line, set step to 2, else step is 1 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 start = x1>x0 ? x0:x1; stop = x1>x0 ? x1:x0; // loop between x pixels for (int x = start; x<= stop ; x+=step) { // do linear interpolation int y = y0 + (y1-y0)*(x-x0)/(x1-x0); if (type == 0) // if 'white' line, turn off pixel clearPixel(x,y); else setPixel(x,y); // else if 'black' or 'dotted' turn on pixel } } else { // ensure we loop from smallest to largest or else for-loop won't run as expected start = y1>y0 ? y0:y1; stop = y1>y0 ? y1:y0; for (int y = start; y<= stop ; y+=step) { // do linear interpolation int x = x0 + (x1-x0)*(y-y0)/(y1-y0); if (type == 0) // if 'white' line, turn off pixel clearPixel(x,y); else setPixel(x,y); // else if 'black' or 'dotted' turn on pixel } } } void N5110::drawRect(int x0,int y0,int width,int height,int fill) { if (fill == 0) { // transparent, just outline drawLine(x0,y0,x0+width,y0,1); // top drawLine(x0,y0+height,x0+width,y0+height,1); // bottom drawLine(x0,y0,x0,y0+height,1); // left drawLine(x0+width,y0,x0+width,y0+height,1); // right } else { // filled rectangle int type = (fill==1) ? 1:0; // black or white fill for (int y = y0; y<= y0+height; y++) { // loop through rows of rectangle drawLine(x0,y,x0+width,y,type); // draw line across screen } } } BMP180::BMP180(PinName sdaPin, PinName sclPin) { i2c = new I2C(sdaPin,sclPin); // create new I2C instance and initialise i2c->frequency(400000); // I2C Fast Mode - 400kHz leds = new BusOut(LED4,LED3,LED2,LED1); } Measurement BMP180::readValues() { // algorithm for taking measurement is taken from datasheet int32_t UT = readUncompensatedTemperatureValue(); int32_t UP = readUncompensatedPressureValue(); // once you have the uncompensated T and P, you can calculate the true T and P // using the equations from the datasheet int32_t T = calcTrueTemperature(UT); int32_t P = calcTruePressure(UP); Measurement measurement; measurement.temperature = T*0.1; // scaled by 0.1 C measurement.pressure = P*0.01; // Put pressure in mb return measurement; } int32_t BMP180::readUncompensatedTemperatureValue() { // from algorithm in datasheet - p15 sendByteToRegister(0x2E,0xF4); wait_ms(5); // 4.5 ms delay for OSS = 1 char MSB = readByteFromRegister(0xF6); char LSB = readByteFromRegister(0xF7); // combine in 16-bit value int UT = (MSB << 8) | LSB; #ifdef DEBUG UT = 27898; // test data from datasheet printf("****DEBUG MODE****\nUT = %d\n",UT); #endif return UT; } int32_t BMP180::readUncompensatedPressureValue() { // from datasheet char byte = 0x34 + (oss << 6); sendByteToRegister(byte,0xF4); wait_ms(8); // 7.5 ms delay for OSS = 1 char MSB = readByteFromRegister(0xF6); char LSB = readByteFromRegister(0xF7); char XLSB = readByteFromRegister(0xF7); int UP = (MSB << 16 | LSB << 8 | XLSB) >> (8 - oss); #ifdef DEBUG UP = 23843; // test data from datasheet printf("UP = %d\n",UP); #endif return UP; } int32_t BMP180::calcTrueTemperature(int32_t UT) { // equations from data sheet X1 = ((UT - calibration.AC6)*calibration.AC5) >> 15; X2 = (calibration.MC << 11) / (X1 + calibration.MD); B5 = X1 + X2; int32_t T = (B5 + 8) >> 4; #ifdef DEBUG printf("****\nX1=%d\nX2=%d\nB5=%d\nT=%d\n",X1,X2,B5,T); #endif return T; } int32_t BMP180::calcTruePressure(int32_t UP) { // equations from data sheet B6 = B5 - 4000; X1 = (calibration.B2 * ((B6*B6) >> 12))>>11; X2 = (calibration.AC2*B6)>>11; X3 = X1 + X2; B3 = (((calibration.AC1*4 + X3) << oss)+2)/4; #ifdef DEBUG printf("*****\nB6=%d\nX1=%d\nX2=%d\nX3=%d\nB3=%d\n",B6,X1,X2,X3,B3); #endif X1 = (calibration.AC3*B6)>>13; X2 = (calibration.B1*((B6*B6)>>12))>>16; X3 = ((X1+X2)+2)/4; B4 = (calibration.AC4*(uint32_t)(X3+32768))>>15; #ifdef DEBUG printf("X1=%d\nX2=%d\nX3=%d\nB4=%u\n",X1,X2,X3,B4); #endif B7 = ((uint32_t)UP - B3)*(50000>>oss); #ifdef DEBUG printf("B7=%u\n",B7); #endif int32_t P; if (B7 < 0x80000000) P = (B7*2)/B4; else P = (B7/B4)*2; #ifdef DEBUG printf("P=%d\n",P); #endif X1 = (P>>8)*(P>>8); #ifdef DEBUG printf("X1=%d\n",X1); #endif X1 = (X1*3038)>>16; #ifdef DEBUG printf("X1=%d\n",X1); #endif X2 = (-7357*P)>>16; #ifdef DEBUG printf("X2=%d\n",X2); #endif P = P + (X1+X2+3791)/16; #ifdef DEBUG printf("P=%d\n",P); #endif return P; } // configure the barometer void BMP180::init() { i2c->frequency(400000); // set Fast Mode I2C frequency char data = readByteFromRegister(ID_REG); // Section 4 - datasheet if (data != 0x55) { // if correct ID not found, hang and flash error message error(); } readCalibrationData(); oss = 1; // standard power oversampling setting #ifdef DEBUG oss = 0; // used when testing data sheet example #endif } // Reads factory calibrated data void BMP180::readCalibrationData() { char eeprom[22]; readBytesFromRegister(EEPROM_REG_ADD,22,eeprom); // store calibration data in structure calibration.AC1 = (int16_t) (eeprom[0] << 8) | eeprom[1]; calibration.AC2 = (int16_t) (eeprom[2] << 8) | eeprom[3]; calibration.AC3 = (int16_t) (eeprom[4] << 8) | eeprom[5]; calibration.AC4 = (uint16_t) (eeprom[6] << 8) | eeprom[7]; calibration.AC5 = (uint16_t) (eeprom[8] << 8) | eeprom[9]; calibration.AC6 = (uint16_t) (eeprom[10] << 8) | eeprom[11]; calibration.B1 = (int16_t) (eeprom[12] << 8) | eeprom[13]; calibration.B2 = (int16_t) (eeprom[14] << 8) | eeprom[15]; calibration.MB = (int16_t) (eeprom[16] << 8) | eeprom[17]; calibration.MC = (int16_t) (eeprom[18] << 8) | eeprom[19]; calibration.MD = (int16_t) (eeprom[20] << 8) | eeprom[21]; // test data from data sheet #ifdef DEBUG calibration.AC1 = 408; calibration.AC2 = -72; calibration.AC3 = -14383; calibration.AC4 = 32741; calibration.AC5 = 32757; calibration.AC6 = 23153; calibration.B1 = 6190; calibration.B2 = 4; calibration.MB = -32768; calibration.MC = -8711; calibration.MD = 2868; printf("****EXAMPLE CALIBRATION DATA****\n"); printf("AC1=%d\nAC2=%d\nAC3=%d\nAC4=%u\nAC5=%u\nAC6=%u\nB1=%d\nB2=%d\nMB=%d\nMC=%d\nMD=%d\n", calibration.AC1,calibration.AC2,calibration.AC3,calibration.AC4,calibration.AC5,calibration.AC6, calibration.B1,calibration.B2,calibration.MB,calibration.MC,calibration.MD); #endif } // reads a byte from a specific register char BMP180::readByteFromRegister(char reg) { int nack = i2c->write(BMP180_W_ADDRESS,®,1,true); // send the register address to the slave if (nack) error(); // if we don't receive acknowledgement, flash error message char rx; nack = i2c->read(BMP180_W_ADDRESS,&rx,1); // read a byte from the register and store in buffer if (nack) error(); // if we don't receive acknowledgement, flash error message return rx; } // reads a series of bytes, starting from a specific register void BMP180::readBytesFromRegister(char reg,int numberOfBytes,char bytes[]) { int nack = i2c->write(BMP180_W_ADDRESS,®,1,true); // send the slave write address and the configuration register address if (nack) error(); // if we don't receive acknowledgement, flash error message nack = i2c->read(BMP180_W_ADDRESS,bytes,numberOfBytes); // read bytes if (nack) error(); // if we don't receive acknowledgement, flash error message } // sends a byte to a specific register void BMP180::sendByteToRegister(char byte,char reg) { char data[2]; data[0] = reg; data[1] = byte; // send the register address, followed by the data int nack = i2c->write(BMP180_W_ADDRESS,data,2); if (nack) error(); // if we don't receive acknowledgement, flash error message } void BMP180::error() { while(1) { leds->write(15); wait(0.1); leds->write(0); wait(0.1); } } N5110 lcd(p7,p8,p9,p10,p11,p13,p26);//The ports being connected of the mbed BusOut leds(LED4,LED3,LED2,LED1);//The ports being connected of the LCD BMP180 bmp180(p28,p27);//The ports being connected to the sensor Serial serial(USBTX,USBRX);//Timer set-up tool //Define the variable void serialISR();//ISR that is called when serial data is received void setTime();// function to set the UNIX time int setTimerFlag = 0;// flag for ISR char rxString[16];//Create a 16 chars row to display the data int main() { lcd.init(); bmp180.init();//Display the word before the sensor data lcd.printString("Weather",0,0);//At the location (0,0),display word "Weather" lcd.printString("Station",1,3);//At the location (1,3),display word "Station" wait(2.0);//The word above stay for 2s lcd.clear();//Clean the display for the continued work Measurement measurement; serial.attach(&serialISR);//attach serial ISR char t[30];//Create a 30 chars row to display the time while(1) { time_t seconds = time(NULL);//get current time // format time into a string (time and date) strftime(t, 30 , "%X %D",localtime(&seconds));// // print over serial serial.printf("Time = %s\n" ,t);//Display the timer lcd.printString(t,0,5);//The location of the timer if(setTimerFlag) {// if updated time has been sent setTimerFlag = 0;//clear flag setTime();// update time } measurement = bmp180.readValues();// char T[14];//Create a 14 chars row to display the temperature int length =sprintf(T,"T = %.2f C",measurement.temperature);//Set up "T = sensor data" as the thing will be shown if (length <= 14)//Judge the length of chars lcd.printString(T,0,1);//The location of the T will be shown char P[14];//Create a 14 chars row to display the pressure length = sprintf(P,"P = %.2f mb",measurement.pressure);//Set up "P = sensor data" as the thing will be shown lcd.printString(P,0,3); //The location of the P will be shown wait(1);//Repeat the circulate each 1s lcd.clear(); //Clear the data for next processing } } void setTime()//// print time for debugging { serial.printf("set_time - %s",rxString); //// atoi() converts a string to an integer int time = atoi(rxString); //update the time set_time(time); } void serialISR()// when a serial interrupt occurs, read rx string into buffer { serial.gets(rxString,16); //// set flag setTimerFlag = 1; }