Marco Rubio / Mbed 2 deprecated RTOS-LED

Example code displaying how to use and implement the mbed RTOS along with a simple state machine used to capture button presses.

Dependencies:   mbed

Fork of mbed-rtos by mbed official

main.cpp@106:1b09dd92c3f1, 2016-02-25 (annotated)

Committer:
gelmes
Date:
Thu Feb 25 17:17:04 2016 +0000
Revision:
106:1b09dd92c3f1
Parent:
105:d7ee57473fdb 
Simple Color Changing LED. USER_MODE button used as input to switch LED animation state. Simple Button press state machine used.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
gelmes 105:d7ee57473fdb 1
gelmes 105:d7ee57473fdb 2 #include "mbed.h"
gelmes 105:d7ee57473fdb 3 #include "rtos.h"
gelmes 105:d7ee57473fdb 4 #include "color.h"
gelmes 105:d7ee57473fdb 5
gelmes 105:d7ee57473fdb 6
gelmes 105:d7ee57473fdb 7 //Set Up all basic colors
gelmes 105:d7ee57473fdb 8 Color black(0.0f,0.0f,0.0f);
gelmes 105:d7ee57473fdb 9 Color red(1.0f,0.0f,0.0f);
gelmes 105:d7ee57473fdb 10 Color yellow(1.0f,1.0f,0.0f);
gelmes 105:d7ee57473fdb 11 Color green(0.0f,1.0f,0.0f);
gelmes 105:d7ee57473fdb 12 Color teal(0.0f,1.0f,1.0f);
gelmes 105:d7ee57473fdb 13 Color blue(0.0f,0.0f,1.0f);
gelmes 105:d7ee57473fdb 14 Color purple(1.0f,0.0f,1.0f);
gelmes 105:d7ee57473fdb 15
gelmes 106:1b09dd92c3f1 16 //PWM pins used D12, D11, D10
gelmes 105:d7ee57473fdb 17 PwmOut ledr(D12);
gelmes 105:d7ee57473fdb 18 PwmOut ledg(D11);
gelmes 105:d7ee57473fdb 19 PwmOut ledb(D10);
gelmes 105:d7ee57473fdb 20 DigitalIn btn(USER_BUTTON);
gelmes 105:d7ee57473fdb 21 DigitalOut led(LED1);
gelmes 105:d7ee57473fdb 22
gelmes 106:1b09dd92c3f1 23 int state = 0; //State of the button animation
gelmes 106:1b09dd92c3f1 24
gelmes 106:1b09dd92c3f1 25 /** Fades LED from one value to the next to calculate animation time
gelmes 106:1b09dd92c3f1 26 multiply steps by stepTime
gelmes 105:d7ee57473fdb 27
gelmes 106:1b09dd92c3f1 28 @param start Starting clor
gelmes 106:1b09dd92c3f1 29 @param finish Ending color
gelmes 106:1b09dd92c3f1 30 @param step Steps to take to get to color
gelmes 106:1b09dd92c3f1 31 @param setTime Time taken by each step
gelmes 106:1b09dd92c3f1 32 */
gelmes 105:d7ee57473fdb 33 bool fadeTo(Color start, Color finish, float steps, double stepTime)
gelmes 105:d7ee57473fdb 34 {
gelmes 105:d7ee57473fdb 35 float rSteps = (finish.r - start.r)/steps;
gelmes 105:d7ee57473fdb 36 float gSteps = (finish.g - start.g)/steps;
gelmes 105:d7ee57473fdb 37 float bSteps = (finish.b - start.b)/steps;
gelmes 105:d7ee57473fdb 38
gelmes 105:d7ee57473fdb 39 steps = 1/steps;
gelmes 105:d7ee57473fdb 40
gelmes 105:d7ee57473fdb 41 float rStepsCounter = 1.0f - start.r;
gelmes 105:d7ee57473fdb 42 float gStepsCounter = 1.0f - start.g;
gelmes 105:d7ee57473fdb 43 float bStepsCounter = 1.0f - start.b;
gelmes 105:d7ee57473fdb 44 int stateBefore = state; //Used as a temporary variable
gelmes 105:d7ee57473fdb 45 // and print what the measured voltage should be (assuming VCC = 3.3v)
gelmes 105:d7ee57473fdb 46 for (float i = 0.0f; i < 1.0f; i += steps) {
gelmes 105:d7ee57473fdb 47 rStepsCounter -= rSteps;
gelmes 105:d7ee57473fdb 48 gStepsCounter -= gSteps;
gelmes 105:d7ee57473fdb 49 bStepsCounter -= bSteps;
gelmes 105:d7ee57473fdb 50
gelmes 105:d7ee57473fdb 51 ledr = rStepsCounter ;
gelmes 105:d7ee57473fdb 52 ledg = gStepsCounter;
gelmes 105:d7ee57473fdb 53 ledb = bStepsCounter;
gelmes 105:d7ee57473fdb 54
gelmes 105:d7ee57473fdb 55 Thread::wait(stepTime*1000);
gelmes 105:d7ee57473fdb 56 if (stateBefore != state) return 0;
gelmes 105:d7ee57473fdb 57 }
gelmes 105:d7ee57473fdb 58 return 1;
gelmes 105:d7ee57473fdb 59 }
gelmes 105:d7ee57473fdb 60
gelmes 106:1b09dd92c3f1 61 /** Fades LED through all standard colors (black, red, yellow, green, teal, blue, purple)
gelmes 106:1b09dd92c3f1 62 to calculate animation time multiply steps by stepTime by 7
gelmes 106:1b09dd92c3f1 63
gelmes 106:1b09dd92c3f1 64 @param steps Number of steps to take
gelmes 106:1b09dd92c3f1 65 @param stepTime Time taken by each step
gelmes 106:1b09dd92c3f1 66 */
gelmes 105:d7ee57473fdb 67 void fadeThruAll(float steps, float stepTime)
gelmes 105:d7ee57473fdb 68 {
gelmes 105:d7ee57473fdb 69 bool cont = 1;
gelmes 105:d7ee57473fdb 70 cont = fadeTo(black, red, steps, stepTime);
gelmes 105:d7ee57473fdb 71 if(cont) cont = fadeTo(red, yellow, steps, stepTime);
gelmes 105:d7ee57473fdb 72 if(cont) cont = fadeTo(yellow, green, steps, stepTime);
gelmes 105:d7ee57473fdb 73 if(cont) cont = fadeTo(green, teal, steps, stepTime);
gelmes 105:d7ee57473fdb 74 if(cont) cont = fadeTo(teal, blue, steps, stepTime);
gelmes 105:d7ee57473fdb 75 if(cont) cont = fadeTo(blue, purple, steps, stepTime);
gelmes 105:d7ee57473fdb 76 if(cont) cont = fadeTo(purple, black, steps, stepTime);
gelmes 105:d7ee57473fdb 77 }
gelmes 105:d7ee57473fdb 78
gelmes 106:1b09dd92c3f1 79
gelmes 106:1b09dd92c3f1 80 /** This is the thread used for controlling the LED rendering state. This state
gelmes 106:1b09dd92c3f1 81 is modified by the btnPresses process through the use of the state global
gelmes 106:1b09dd92c3f1 82 variable.
gelmes 106:1b09dd92c3f1 83 */
gelmes 105:d7ee57473fdb 84 void renderColors(void const * arg)
gelmes 105:d7ee57473fdb 85 {
gelmes 105:d7ee57473fdb 86 while (1) {
gelmes 105:d7ee57473fdb 87 switch(state) {
gelmes 105:d7ee57473fdb 88 case 0:
gelmes 105:d7ee57473fdb 89 fadeThruAll(100.0f, 0.025f);
gelmes 105:d7ee57473fdb 90 break;
gelmes 105:d7ee57473fdb 91 case 1:
gelmes 105:d7ee57473fdb 92 fadeThruAll(1.0f,0.1f);
gelmes 105:d7ee57473fdb 93 break;
gelmes 105:d7ee57473fdb 94 case 2:
gelmes 105:d7ee57473fdb 95 state = 0;
gelmes 105:d7ee57473fdb 96 break;
gelmes 105:d7ee57473fdb 97 default:
gelmes 105:d7ee57473fdb 98 state = 0;
gelmes 105:d7ee57473fdb 99 break;
gelmes 105:d7ee57473fdb 100 }
gelmes 105:d7ee57473fdb 101 }
gelmes 105:d7ee57473fdb 102 }
gelmes 105:d7ee57473fdb 103
gelmes 105:d7ee57473fdb 104 enum SMBtnStates {SMBtnStart, SMBtnPressedOff, SMBtnUnpressedOff, SMBtnPressedOn, SMBtnUnpressedOn} SMBtnState;
gelmes 106:1b09dd92c3f1 105 /** This is the thread used to gather button presses information. This is a simple State machine of a button
gelmes 106:1b09dd92c3f1 106 press.
gelmes 106:1b09dd92c3f1 107 ___________ _______________
gelmes 106:1b09dd92c3f1 108 | | | |
gelmes 106:1b09dd92c3f1 109 |SMBtn Start| -> |SMBtnPressedOFF|
gelmes 106:1b09dd92c3f1 110 |___________| |_______________|
gelmes 106:1b09dd92c3f1 111 */
gelmes 105:d7ee57473fdb 112 void btnPresses(void const * arg)
gelmes 105:d7ee57473fdb 113 {
gelmes 105:d7ee57473fdb 114 while(1) {
gelmes 105:d7ee57473fdb 115 switch(SMBtnState) {
gelmes 105:d7ee57473fdb 116 case SMBtnStart:
gelmes 105:d7ee57473fdb 117 SMBtnState = SMBtnUnpressedOff;
gelmes 105:d7ee57473fdb 118 break;
gelmes 105:d7ee57473fdb 119 case SMBtnUnpressedOff:
gelmes 105:d7ee57473fdb 120 if(!btn) SMBtnState = SMBtnPressedOn;
gelmes 105:d7ee57473fdb 121 break;
gelmes 105:d7ee57473fdb 122 case SMBtnPressedOn:
gelmes 105:d7ee57473fdb 123 if(btn) {
gelmes 105:d7ee57473fdb 124 SMBtnState = SMBtnUnpressedOn;
gelmes 105:d7ee57473fdb 125 state++;
gelmes 105:d7ee57473fdb 126 led = 1;
gelmes 105:d7ee57473fdb 127 }
gelmes 105:d7ee57473fdb 128 break;
gelmes 105:d7ee57473fdb 129 case SMBtnUnpressedOn:
gelmes 105:d7ee57473fdb 130 if(!btn) SMBtnState = SMBtnPressedOff;
gelmes 105:d7ee57473fdb 131 break;
gelmes 105:d7ee57473fdb 132 case SMBtnPressedOff:
gelmes 105:d7ee57473fdb 133 if(btn) {
gelmes 105:d7ee57473fdb 134 SMBtnState = SMBtnUnpressedOff;
gelmes 105:d7ee57473fdb 135 state++;
gelmes 105:d7ee57473fdb 136 led = 0;
gelmes 105:d7ee57473fdb 137 }
gelmes 105:d7ee57473fdb 138 break;
gelmes 105:d7ee57473fdb 139 default:
gelmes 105:d7ee57473fdb 140 SMBtnState = SMBtnStart;
gelmes 105:d7ee57473fdb 141 break;
gelmes 105:d7ee57473fdb 142 }
gelmes 105:d7ee57473fdb 143
gelmes 105:d7ee57473fdb 144 switch(SMBtnState) {
gelmes 105:d7ee57473fdb 145 case SMBtnStart:
gelmes 105:d7ee57473fdb 146 SMBtnState = SMBtnUnpressedOff;
gelmes 105:d7ee57473fdb 147 break;
gelmes 105:d7ee57473fdb 148 case SMBtnUnpressedOff:
gelmes 105:d7ee57473fdb 149 break;
gelmes 105:d7ee57473fdb 150 case SMBtnPressedOn:
gelmes 105:d7ee57473fdb 151 break;
gelmes 105:d7ee57473fdb 152 case SMBtnUnpressedOn:
gelmes 105:d7ee57473fdb 153 break;
gelmes 105:d7ee57473fdb 154 case SMBtnPressedOff:
gelmes 105:d7ee57473fdb 155 break;
gelmes 105:d7ee57473fdb 156 default:
gelmes 105:d7ee57473fdb 157 SMBtnState = SMBtnStart;
gelmes 105:d7ee57473fdb 158 break;
gelmes 105:d7ee57473fdb 159 }
gelmes 105:d7ee57473fdb 160 }
gelmes 105:d7ee57473fdb 161 }
gelmes 105:d7ee57473fdb 162
gelmes 106:1b09dd92c3f1 163 /** Main thread control
gelmes 106:1b09dd92c3f1 164 */
gelmes 105:d7ee57473fdb 165 int main()
gelmes 105:d7ee57473fdb 166 {
gelmes 105:d7ee57473fdb 167 Thread thread1(renderColors);
gelmes 105:d7ee57473fdb 168 Thread thread2(btnPresses);
gelmes 105:d7ee57473fdb 169 while(true) {};
gelmes 105:d7ee57473fdb 170 }