Matt Shilling / Mbed 2 deprecated Waveform_Generator

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Dependencies:   SLCD TSI mbed

main.cpp@0:fb56047b523f, 2016-09-29 (annotated)

Committer:
MattShilling
Date:
Thu Sep 29 21:58:33 2016 +0000
Revision:
0:fb56047b523f
Child:
1:36dabc12aa01
this is a program that will create waveforms with the Analog out pin (18)

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MattShilling 0:fb56047b523f 1 //***************************************************************
MattShilling 0:fb56047b523f 2 // Function Generator - main entry and sole source file for an
MattShilling 0:fb56047b523f 3 // MBED based function generator. The program will output
MattShilling 0:fb56047b523f 4 // waveforms sinewave, squarewave, sawtooth, and flat DC on the
MattShilling 0:fb56047b523f 5 // MBED analog out pin (P18). The joystick buttons are used
MattShilling 0:fb56047b523f 6 // to control the period and amplitude of the output waveforms.
MattShilling 0:fb56047b523f 7 // This is because the pots are a little too unstable to be read
MattShilling 0:fb56047b523f 8 // out in a tight update loop for the waveforms. The exception
MattShilling 0:fb56047b523f 9 // is the DC output. That uses the pot as it doesn't need a tight
MattShilling 0:fb56047b523f 10 // loop.
MattShilling 0:fb56047b523f 11 //
MattShilling 0:fb56047b523f 12 // Author: Terry Richards
MattShilling 0:fb56047b523f 13 // Date: 5/29/2014
MattShilling 0:fb56047b523f 14 //
MattShilling 0:fb56047b523f 15 #include "mbed.h"
MattShilling 0:fb56047b523f 16 #include "SLCD.h"
MattShilling 0:fb56047b523f 17 #include "TSISensor.h"
MattShilling 0:fb56047b523f 18
MattShilling 0:fb56047b523f 19 //Serial output for debug
MattShilling 0:fb56047b523f 20 //Serial pc(USBTX, USBRX);
MattShilling 0:fb56047b523f 21
MattShilling 0:fb56047b523f 22 SLCD lcd; //create lcd class
MattShilling 0:fb56047b523f 23 TSISensor tsi; // touch sensor
MattShilling 0:fb56047b523f 24 Serial pc(USBTX, USBRX); //init serial
MattShilling 0:fb56047b523f 25
MattShilling 0:fb56047b523f 26 AnalogOut Aout(PTE30); // waveform will be outputted through this pin
MattShilling 0:fb56047b523f 27 DigitalIn sw_right(SW1);
MattShilling 0:fb56047b523f 28 DigitalIn sw_left(SW3);
MattShilling 0:fb56047b523f 29
MattShilling 0:fb56047b523f 30
MattShilling 0:fb56047b523f 31 bool first = true;
MattShilling 0:fb56047b523f 32 bool just_pressed = false;
MattShilling 0:fb56047b523f 33 int select = 1;
MattShilling 0:fb56047b523f 34
MattShilling 0:fb56047b523f 35 // check_update - checks the buttons to see if the user wants
MattShilling 0:fb56047b523f 36 // to update either the vertical (in volts) or the horizontal
MattShilling 0:fb56047b523f 37 // (in uS) for the currently selected waveform. It also updates
MattShilling 0:fb56047b523f 38 // the LCD
MattShilling 0:fb56047b523f 39 // **** The joystick is used instead of the pots because *****
MattShilling 0:fb56047b523f 40 // **** I found that the pots were to unstable ***************
MattShilling 0:fb56047b523f 41 // Inputs - the vert and horiz from the calling waveform routine
MattShilling 0:fb56047b523f 42 // Outputs - the updated vert and horiz based on the button presses
MattShilling 0:fb56047b523f 43 //
MattShilling 0:fb56047b523f 44 #define SINE 1
MattShilling 0:fb56047b523f 45 #define SQUARE 2
MattShilling 0:fb56047b523f 46 #define SAW 3
MattShilling 0:fb56047b523f 47
MattShilling 0:fb56047b523f 48
MattShilling 0:fb56047b523f 49 void check_click_right()
MattShilling 0:fb56047b523f 50 {
MattShilling 0:fb56047b523f 51 if (sw_right == 0)
MattShilling 0:fb56047b523f 52 {
MattShilling 0:fb56047b523f 53 just_pressed = true;
MattShilling 0:fb56047b523f 54 }
MattShilling 0:fb56047b523f 55
MattShilling 0:fb56047b523f 56 if (sw_right == 1 && just_pressed == true)
MattShilling 0:fb56047b523f 57 {
MattShilling 0:fb56047b523f 58 select++;
MattShilling 0:fb56047b523f 59 if (select == 4) select = 1;
MattShilling 0:fb56047b523f 60 just_pressed = false;
MattShilling 0:fb56047b523f 61 pc.printf("selection %d \n", select);
MattShilling 0:fb56047b523f 62 }
MattShilling 0:fb56047b523f 63
MattShilling 0:fb56047b523f 64 }
MattShilling 0:fb56047b523f 65
MattShilling 0:fb56047b523f 66 void check_update( int type, //what type of waveform
MattShilling 0:fb56047b523f 67 double *vert, //vertical in volts
MattShilling 0:fb56047b523f 68 int *horiz, //horizontal in microseconds (uS)
MattShilling 0:fb56047b523f 69 float vertmax, //max vertical in volts
MattShilling 0:fb56047b523f 70 int horizmax, //max horizontal in us
MattShilling 0:fb56047b523f 71 bool disp_info ) //put initial vert and horiz
MattShilling 0:fb56047b523f 72 { //on LCD screen if set
MattShilling 0:fb56047b523f 73 if( type ) { //The header is static once the waveform is chosen
MattShilling 0:fb56047b523f 74 lcd.clear();
MattShilling 0:fb56047b523f 75 lcd.Home();
MattShilling 0:fb56047b523f 76 switch( type ) { //only done if type is set
MattShilling 0:fb56047b523f 77 case SINE:
MattShilling 0:fb56047b523f 78 lcd.printf("sin");
MattShilling 0:fb56047b523f 79 break;
MattShilling 0:fb56047b523f 80 case SQUARE:
MattShilling 0:fb56047b523f 81 lcd.printf("sqr");
MattShilling 0:fb56047b523f 82 break;
MattShilling 0:fb56047b523f 83 case SAW:
MattShilling 0:fb56047b523f 84 lcd.printf("saw");
MattShilling 0:fb56047b523f 85 }
MattShilling 0:fb56047b523f 86 }
MattShilling 0:fb56047b523f 87
MattShilling 0:fb56047b523f 88 if(tsi.readPercentage() != 0
MattShilling 0:fb56047b523f 89 && tsi.readPercentage() < (1.0 - 0.001)) {
MattShilling 0:fb56047b523f 90
MattShilling 0:fb56047b523f 91 if (sw_left == 1) {
MattShilling 0:fb56047b523f 92 *vert = tsi.readPercentage(); //update the vertical
MattShilling 0:fb56047b523f 93 pc.printf("Height Changed to: %f \n", *vert);
MattShilling 0:fb56047b523f 94 }
MattShilling 0:fb56047b523f 95
MattShilling 0:fb56047b523f 96 }
MattShilling 0:fb56047b523f 97
MattShilling 0:fb56047b523f 98
MattShilling 0:fb56047b523f 99 if(tsi.readPercentage() != 0
MattShilling 0:fb56047b523f 100 && sw_left == 0 ) { //updates the horizontal in us
MattShilling 0:fb56047b523f 101
MattShilling 0:fb56047b523f 102 *horiz = int(tsi.readPercentage() * 1000);
MattShilling 0:fb56047b523f 103 pc.printf("Period Changed to: %d \n", *horiz);
MattShilling 0:fb56047b523f 104 }
MattShilling 0:fb56047b523f 105
MattShilling 0:fb56047b523f 106 if(disp_info) { //only done if bool is true
MattShilling 0:fb56047b523f 107 //pc.printf("PW/Period: %d uS \n", *horiz);
MattShilling 0:fb56047b523f 108 //pc.printf("Height: %5.3f V \n\n", *vert);
MattShilling 0:fb56047b523f 109 }
MattShilling 0:fb56047b523f 110
MattShilling 0:fb56047b523f 111 check_click_right();
MattShilling 0:fb56047b523f 112
MattShilling 0:fb56047b523f 113 }
MattShilling 0:fb56047b523f 114
MattShilling 0:fb56047b523f 115 // SineWave - is initiated when the user selects sinewave output
MattShilling 0:fb56047b523f 116 // Sends a sine wave to the Aout pin.
MattShilling 0:fb56047b523f 117 // The Touch Slider controls amplitude
MattShilling 0:fb56047b523f 118 // The Touch Slider + left button controls the period
MattShilling 0:fb56047b523f 119 void sineWave()
MattShilling 0:fb56047b523f 120 {
MattShilling 0:fb56047b523f 121 int horiz=1000;
MattShilling 0:fb56047b523f 122 double vert=1.0, outval, i;
MattShilling 0:fb56047b523f 123 check_update( SINE, &vert, &horiz, 1.0, 10000, true );
MattShilling 0:fb56047b523f 124 while(select == SINE) { // thread loop
MattShilling 0:fb56047b523f 125 check_update( 0, &vert, &horiz, 1.0, 10000, false );
MattShilling 0:fb56047b523f 126 for (i=0; i<2; i=i+0.05) {
MattShilling 0:fb56047b523f 127 outval = 0.5 + 0.5*vert*sin(i*3.14159);
MattShilling 0:fb56047b523f 128 Aout.write(outval); // Compute the sine value, + half the range
MattShilling 0:fb56047b523f 129 wait_us(horiz); // Controls the sine wave period
MattShilling 0:fb56047b523f 130 }
MattShilling 0:fb56047b523f 131 }
MattShilling 0:fb56047b523f 132
MattShilling 0:fb56047b523f 133 first = true;
MattShilling 0:fb56047b523f 134 }
MattShilling 0:fb56047b523f 135
MattShilling 0:fb56047b523f 136 // squareWave - called if user selects squarewave. Sends the
MattShilling 0:fb56047b523f 137 // square wave to the Aout pin.
MattShilling 0:fb56047b523f 138 // The Touch Slider controls amplitude
MattShilling 0:fb56047b523f 139 // The Touch Slider + left button controls the period
MattShilling 0:fb56047b523f 140 void squareWave()
MattShilling 0:fb56047b523f 141 {
MattShilling 0:fb56047b523f 142 static double height = 1.0;
MattShilling 0:fb56047b523f 143 static int width = 20;
MattShilling 0:fb56047b523f 144 check_update( SQUARE, &height, &width, 1.0, 10000, true );
MattShilling 0:fb56047b523f 145 while(select == SQUARE) { // thread loop
MattShilling 0:fb56047b523f 146 check_update( 0, &height, &width, 1.0, 100000, false );
MattShilling 0:fb56047b523f 147 Aout.write(height);
MattShilling 0:fb56047b523f 148 wait_us(width);
MattShilling 0:fb56047b523f 149 Aout.write(0);
MattShilling 0:fb56047b523f 150 wait_us(width);
MattShilling 0:fb56047b523f 151 }
MattShilling 0:fb56047b523f 152
MattShilling 0:fb56047b523f 153 first = true;
MattShilling 0:fb56047b523f 154 }
MattShilling 0:fb56047b523f 155
MattShilling 0:fb56047b523f 156 // SawTooth - called if the user selects sawTooth. Sends the
MattShilling 0:fb56047b523f 157 // saw tooth waveform out to the Aout pin.
MattShilling 0:fb56047b523f 158 // The up and down buttons of the joystick control the amplitude
MattShilling 0:fb56047b523f 159 // The right and left buttons control the period
MattShilling 0:fb56047b523f 160 void sawTooth()
MattShilling 0:fb56047b523f 161 {
MattShilling 0:fb56047b523f 162 static double height = 1.0, inc;
MattShilling 0:fb56047b523f 163 static int width = 6000, i;
MattShilling 0:fb56047b523f 164 inc = height/width;
MattShilling 0:fb56047b523f 165 check_update( SAW, &height, &width, 1.0, 10000, true );
MattShilling 0:fb56047b523f 166 while(select == SAW) { // thread loop
MattShilling 0:fb56047b523f 167 check_update( 0, &height, &width, 1.0, 100000, false );
MattShilling 0:fb56047b523f 168 inc = height/width;
MattShilling 0:fb56047b523f 169 for( i=0; i<width; i++) {
MattShilling 0:fb56047b523f 170 Aout.write(i*inc);
MattShilling 0:fb56047b523f 171 //wait_us(1);
MattShilling 0:fb56047b523f 172 }
MattShilling 0:fb56047b523f 173 }
MattShilling 0:fb56047b523f 174
MattShilling 0:fb56047b523f 175 first = true;
MattShilling 0:fb56047b523f 176 }
MattShilling 0:fb56047b523f 177 // Banner - Output a welcome and select screen for
MattShilling 0:fb56047b523f 178 // the user and give them instructions for use
MattShilling 0:fb56047b523f 179 void banner(){
MattShilling 0:fb56047b523f 180
MattShilling 0:fb56047b523f 181 pc.printf("WELCOME TO THE FRDM-KL46Z WAVEFORM GENERATOR \n");
MattShilling 0:fb56047b523f 182 pc.printf("Writen by Matt Shilling based on code from Terry Richards \n\n");
MattShilling 0:fb56047b523f 183 pc.printf("---------------------- INSTRUCTIONS ----------------------\n");
MattShilling 0:fb56047b523f 184 pc.printf("1.) Click right button to select waveform\n");
MattShilling 0:fb56047b523f 185 pc.printf("2.) Use touch slider to control wave amplitude\n");
MattShilling 0:fb56047b523f 186 pc.printf("3.) Use touch slider + left putton to control wave period\n");
MattShilling 0:fb56047b523f 187
MattShilling 0:fb56047b523f 188 }
MattShilling 0:fb56047b523f 189
MattShilling 0:fb56047b523f 190 // main - main entry point to program and where the
MattShilling 0:fb56047b523f 191 // user selects the desired waveform.
MattShilling 0:fb56047b523f 192 int main()
MattShilling 0:fb56047b523f 193 {
MattShilling 0:fb56047b523f 194 //booleans to select waveform
MattShilling 0:fb56047b523f 195 bool do_sine=false, do_saw=false;
MattShilling 0:fb56047b523f 196 bool do_square=false;
MattShilling 0:fb56047b523f 197 //pc.baud(19200); //debug
MattShilling 0:fb56047b523f 198 banner(); //print instructions on serial
MattShilling 0:fb56047b523f 199 while(1) {
MattShilling 0:fb56047b523f 200 if( select == SAW ) { //is SAW selected?
MattShilling 0:fb56047b523f 201 do_saw=true; //select Sawtooth
MattShilling 0:fb56047b523f 202 do_sine=false; //ensure nothing else selected
MattShilling 0:fb56047b523f 203 do_square=false;
MattShilling 0:fb56047b523f 204 }
MattShilling 0:fb56047b523f 205
MattShilling 0:fb56047b523f 206 if( select == SQUARE ) { //is RIGHT pressed?
MattShilling 0:fb56047b523f 207 do_saw=false;
MattShilling 0:fb56047b523f 208 do_sine=false;
MattShilling 0:fb56047b523f 209 do_square=true; //user wants squarewave
MattShilling 0:fb56047b523f 210 }
MattShilling 0:fb56047b523f 211
MattShilling 0:fb56047b523f 212 if( select == SINE ) { //is LEFT pressed?
MattShilling 0:fb56047b523f 213 do_saw=false;
MattShilling 0:fb56047b523f 214 do_sine=true; //user wants sinewave
MattShilling 0:fb56047b523f 215 do_square=false;
MattShilling 0:fb56047b523f 216 }
MattShilling 0:fb56047b523f 217
MattShilling 0:fb56047b523f 218 if(first ) { //wave has ended
MattShilling 0:fb56047b523f 219
MattShilling 0:fb56047b523f 220 if( do_saw ) {
MattShilling 0:fb56047b523f 221 //pc.printf("I'm doing saw\r\n");
MattShilling 0:fb56047b523f 222 sawTooth();
MattShilling 0:fb56047b523f 223 }
MattShilling 0:fb56047b523f 224 else if( do_square ) {
MattShilling 0:fb56047b523f 225 //pc.printf("I'm doing square\r\n");
MattShilling 0:fb56047b523f 226 squareWave();
MattShilling 0:fb56047b523f 227 }
MattShilling 0:fb56047b523f 228 else if( do_sine ) {
MattShilling 0:fb56047b523f 229 //pc.printf("I'm doing sine\r\n");
MattShilling 0:fb56047b523f 230 sineWave();
MattShilling 0:fb56047b523f 231 }
MattShilling 0:fb56047b523f 232 else { //Default if no button pushed
MattShilling 0:fb56047b523f 233 //pc.printf("I'm doing default (sine)\r\n");
MattShilling 0:fb56047b523f 234 sineWave();
MattShilling 0:fb56047b523f 235 }
MattShilling 0:fb56047b523f 236 //banner(); //we came back, ask user what next
MattShilling 0:fb56047b523f 237 }
MattShilling 0:fb56047b523f 238 }
MattShilling 0:fb56047b523f 239 }