The Accelerometer and Slope program
Dependencies: MMA8452 PowerControl mbed
Diff: N5110.cpp
- Revision:
- 0:7f98d386be37
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/N5110.cpp Mon May 11 21:18:42 2015 +0000 @@ -0,0 +1,551 @@ +/** +@file N5110.cpp + +@brief Member functions implementations +@brief The fundamental code of a Accelerometer and SpiritLevel +@brief SpiritLevel 1.0 +@author Bo Xu +@date May 2015 +*/ +#include "mbed.h" +#include "N5110.h" +#include "MMA8452.h" +#include "PowerControl/PowerControl.h" +#include "PowerControl/EthernetPowerControl.h" + +#define USR_POWERDOWN (0x104) + +/** +@namespace button +@brief AnalogIn for application button +*/ +InterruptIn button(p16); + +#define accelerator 0 +#define slope 1 + +int function = accelerator; +/** +namespace led +@brief Pwmout for SpiritLevel LED +*/ +PwmOut led(p24); + +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); + +} + +/** +initialize the N5110 and declare the pins it connected to the microcontroller +*/ +N5110 lcd(p7, p8, p9, p10, p11, p13, p26); +/** +initialize the MMA8452 sensor and declare the pins it connected to the microcontroller +*/ +MMA8452 mma8452(p28, p27); + +Serial serial (USBTX, USBRX); + +int semihost_powerdown() { + uint32_t arg; + return __semihost(USR_POWERDOWN, &arg); +} + +// 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 for the function button +*/ +void buttonPressed(){ + + function = !function; + +} + +// function to power up the LCD and backlight +void N5110::turnOn() +{ + // set brightness of LED - 0.0 to 1.0 - default is 50% + setBrightness( 0.2); + 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 + } + } + +} + + + +int main(){ + /** + Power down the Ethernet in order to save power + */ + semihost_powerdown(); + + PHY_PowerDown(); + /** + initialize the LCD display and MMA8452 sensor + */ + lcd.init(); + mma8452.init(); + + Acceleration acceleration; + + wait(.001); + + button.rise(&buttonPressed); + + + while (1){ + /** + Read values from the MMA8452 sensor + */ + acceleration = mma8452.readValues(); + + /** + state two different applications of the device + function=0 - Accelerometer + function=1 - Slope + */ + switch(function){ + case accelerator: + + /** + the algorithm of the acceleration + */ + char buffer[14]; + int length = sprintf(buffer,"Acceleration"); + char buffer2[14]; + length = sprintf(buffer2,"x = %.2f g", acceleration.x); + char buffer3[14]; + length = sprintf(buffer3,"y = %.2f g", acceleration.y); + char buffer4[14]; + length = sprintf(buffer4,"z = %.2f g", acceleration.z); + /** + draw a rectangle and print the acceleration + */ + lcd.drawRect(0,0,83,47,0); + lcd.printString(buffer,4,1); + lcd.printString(buffer2,4,2); + lcd.printString(buffer3,4,3); + lcd.printString(buffer4,4,4); + wait(0.1); + lcd.clear(); + break; + + case slope: + /** + algorithm to calculate the angle + */ + char buffer5[14]; + length = sprintf(buffer5, "Slope"); + char buffer6[14]; + length = sprintf(buffer6, "x =%.2f pi", asin(acceleration.x)/3.1415926); + char buffer7[14]; + length = sprintf(buffer7, "y =%.2f pi", asin(acceleration.y)/3.1415926); + /** + draw rectangle and print the data + */ + lcd.drawRect(0,0,83,47,0); + lcd.printString(buffer5,3,1); + lcd.printString(buffer6,3,2); + lcd.printString(buffer7,3,3); + wait(0.1); + lcd.clear(); + + /** + determine if the device is perfect level + when the acceleration on z-axis is greater than 0.95 + the LED will be turned on + */ + if (acceleration.z > 0.95){ + led.write(1); + }else + led.write(0); + + break; + + } + + } + +} \ No newline at end of file