Robert Hill / Mbed 2 deprecated FRDM_HE_

Hall Effect Demo Program, using a hall effect sensor to calculate pedal speed while riding a bike

Dependencies:   mbed

HallEffect.cpp@0:b83e5e826d81, 2016-02-24 (annotated)

Committer:
roberthill04
Date:
Wed Feb 24 17:42:35 2016 +0000
Revision:
0:b83e5e826d81
This is the Hall Effect Demo Program, testing the functionality of the hall effect as a means of finding pedal speed while riding a bike.;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
roberthill04 0:b83e5e826d81 1 #include "mbed.h"
roberthill04 0:b83e5e826d81 2 #include "AnalogIn.h" //not sure if this is necessary
roberthill04 0:b83e5e826d81 3 #include "DigitalIn.h" //^^^
roberthill04 0:b83e5e826d81 4
roberthill04 0:b83e5e826d81 5 DigitalOut led_red(LED_RED);
roberthill04 0:b83e5e826d81 6 DigitalOut led_green(LED_GREEN);
roberthill04 0:b83e5e826d81 7 DigitalOut led_blue(LED_BLUE);
roberthill04 0:b83e5e826d81 8 DigitalIn sw2(SW2);
roberthill04 0:b83e5e826d81 9 DigitalIn sw3(SW3);
roberthill04 0:b83e5e826d81 10 Serial pc(USBTX, USBRX);
roberthill04 0:b83e5e826d81 11
roberthill04 0:b83e5e826d81 12 //LED is ON when set to 0, OFF when set to 1
roberthill04 0:b83e5e826d81 13 ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
roberthill04 0:b83e5e826d81 14 DigitalIn HallEffect(D2); //Intializes Digital input into pin D2 (Hall Effect sensor)
roberthill04 0:b83e5e826d81 15
roberthill04 0:b83e5e826d81 16
roberthill04 0:b83e5e826d81 17 int Hall_Counter = 0; //Initialize Counter for Hall Effect
roberthill04 0:b83e5e826d81 18 bool Low_Hall = true; //Initialize Flag for Hall Effect sensor
roberthill04 0:b83e5e826d81 19 bool Button_Pressed = true; //Initialize flag for output on terminal
roberthill04 0:b83e5e826d81 20 Timer Hall_Timer; //Initialize timer for pedal speed calc
roberthill04 0:b83e5e826d81 21 int Pedal_Time; //Intialize int for Time Passed
roberthill04 0:b83e5e826d81 22 int Pedal_Speed; //Initialize int for Pedal Speed
roberthill04 0:b83e5e826d81 23 ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
roberthill04 0:b83e5e826d81 24
roberthill04 0:b83e5e826d81 25 void Hall_Effect_Count(void)
roberthill04 0:b83e5e826d81 26 {
roberthill04 0:b83e5e826d81 27 if (sw3 == 0 && Button_Pressed == true) {
roberthill04 0:b83e5e826d81 28 //led_blue = 0; //Blue LED is ON
roberthill04 0:b83e5e826d81 29 //led_green = 1;
roberthill04 0:b83e5e826d81 30 //led_red = 1;
roberthill04 0:b83e5e826d81 31 pc.printf("Number of times magnet has passed sensor: %d\n", Hall_Counter); //Outputs # of times magnet passed sensor
roberthill04 0:b83e5e826d81 32 Hall_Timer.stop(); //stop the timer
roberthill04 0:b83e5e826d81 33 pc.printf("Time passed (in seconds): %f \n", Hall_Timer.read()); //Outputs time in seconds
roberthill04 0:b83e5e826d81 34 Pedal_Time=Hall_Timer.read()/60; //Divides Time in seconds by 60 so we have minutes for Pedal_Speed (RPM)
roberthill04 0:b83e5e826d81 35 Pedal_Speed=Hall_Counter/(Hall_Timer.read()/60);
roberthill04 0:b83e5e826d81 36 pc.printf("Approximate pedal speed: %d RPM\n", Pedal_Speed); //Outputs pedal speed
roberthill04 0:b83e5e826d81 37 Button_Pressed = false;
roberthill04 0:b83e5e826d81 38 //Hall_Timer.reset(); //idea here is the timer is reset after the program outputs the pedal speed so the demo can be reran
roberthill04 0:b83e5e826d81 39 }
roberthill04 0:b83e5e826d81 40 }
roberthill04 0:b83e5e826d81 41
roberthill04 0:b83e5e826d81 42 int main() {
roberthill04 0:b83e5e826d81 43 led_blue=1;
roberthill04 0:b83e5e826d81 44 led_red=0;
roberthill04 0:b83e5e826d81 45 led_green=1;
roberthill04 0:b83e5e826d81 46 pc.baud(9600);
roberthill04 0:b83e5e826d81 47 pc.printf("Hello World from FRDM-K64F board. This is the Hall Effect Demo Program. ");
roberthill04 0:b83e5e826d81 48 pc.printf("Press SW3 (Button Near LED on board) to see Pedal Speed.\n ");
roberthill04 0:b83e5e826d81 49 Hall_Timer.start(); //Starts Timer for Pedal Speed Calculation **see if this is better in loop or out**
roberthill04 0:b83e5e826d81 50 //Looks like it works better here (Feb. 10)
roberthill04 0:b83e5e826d81 51
roberthill04 0:b83e5e826d81 52
roberthill04 0:b83e5e826d81 53
roberthill04 0:b83e5e826d81 54
roberthill04 0:b83e5e826d81 55 while (1){ //infinite loop
roberthill04 0:b83e5e826d81 56 //Hall_Timer.start(); //Start the timer ***See if timer works here or above while loop
roberthill04 0:b83e5e826d81 57 Button_Pressed = true;
roberthill04 0:b83e5e826d81 58 if(HallEffect==0 && Low_Hall==true) { //If Hall Effect Digital Output is low
roberthill04 0:b83e5e826d81 59 Hall_Counter++; //Add one to counter for calc pedal speed
roberthill04 0:b83e5e826d81 60 led_green = 0; //Output Green on LED, simulates wheel rotation "sensed"
roberthill04 0:b83e5e826d81 61 led_red = 1;
roberthill04 0:b83e5e826d81 62 led_blue = 1;
roberthill04 0:b83e5e826d81 63 Low_Hall = false; //flag to avoid errors
roberthill04 0:b83e5e826d81 64 }
roberthill04 0:b83e5e826d81 65 else if(HallEffect==1 && Low_Hall==true){ //Additional logic for accurate readings
roberthill04 0:b83e5e826d81 66 led_green = 1;
roberthill04 0:b83e5e826d81 67 led_red = 0; //Stays red while hall effect outputs digital high
roberthill04 0:b83e5e826d81 68 led_blue = 1;
roberthill04 0:b83e5e826d81 69 }
roberthill04 0:b83e5e826d81 70 else if(HallEffect==0 && Low_Hall==false){
roberthill04 0:b83e5e826d81 71 led_green = 0;
roberthill04 0:b83e5e826d81 72 led_red = 1;
roberthill04 0:b83e5e826d81 73 led_blue = 1;
roberthill04 0:b83e5e826d81 74
roberthill04 0:b83e5e826d81 75 }
roberthill04 0:b83e5e826d81 76 else if(HallEffect==1 && Low_Hall==false){
roberthill04 0:b83e5e826d81 77 led_green = 1;
roberthill04 0:b83e5e826d81 78 led_red = 0;
roberthill04 0:b83e5e826d81 79 led_blue = 1;
roberthill04 0:b83e5e826d81 80 Low_Hall = true;
roberthill04 0:b83e5e826d81 81 }
roberthill04 0:b83e5e826d81 82 Hall_Effect_Count();
roberthill04 0:b83e5e826d81 83 //wait(5.0f); //LOOK at this, this may be why the button isnt working****
roberthill04 0:b83e5e826d81 84 }
roberthill04 0:b83e5e826d81 85 }