Library for interfacing to Nokia 5110 LCD display (as found on the SparkFun website).

Dependents:   LV7_LCDtest LV7_Grupa5_Tim003_Zadatak1 lv7_Grupa5_Tim008_zad1 LV7_PAI_Grupa5_tim10_Zadatak1 ... more

This library is designed to make it easy to interface an mbed with a Nokia 5110 LCD display.

These can be found at Sparkfun (https://www.sparkfun.com/products/10168) and Adafruit (http://www.adafruit.com/product/338).

The library uses the SPI peripheral on the mbed which means it is much faster sending data to the display than other libraries available on other platforms that use software SPI.

The library can print strings as well as controlling individual pixels, meaning that both text and primitive graphics can be displayed.

Revision:
0:d563e74f0ae9
Child:
1:df68f34cd32d
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/N5110.cpp	Sun Jan 26 18:55:16 2014 +0000
@@ -0,0 +1,218 @@
+#include "mbed.h"
+#include "N5110.h"
+
+N5110::N5110(PinName pwrPin, PinName ledPin, PinName scePin, PinName rstPin, PinName dcPin, PinName mosiPin, PinName sclkPin)
+{
+    
+    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
+
+    // function set - extended
+    sendCommand(0x20 | CMD_FS_ACTIVE_MODE | CMD_FS_HORIZONTAL_MODE | CMD_FS_EXTENDED_MODE);
+
+    sendCommand(CMD_VOP_7V38);    // operating voltage
+    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);
+    sendCommand(CMD_DC_NORMAL_MODE);  // black on white
+    //sendLCDCommand(CMD_DC_INVERT_VIDEO);  // white on black
+
+    // RAM is undefined at power-up so clear
+    clearRAM();
+
+}
+
+// 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
+    }
+
+}
+
+// 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;
+        }
+    }
+}
\ No newline at end of file