Rob Toulson / Mbed 2 deprecated PE_09-08_ReactionTime

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Dependencies:   mbed

main.cpp@0:2e007d983da0, 2013-05-24 (annotated)

Committer:
robt
Date:
Fri May 24 21:49:03 2013 +0000
Revision:
0:2e007d983da0
by Rob Toulson and Tim Wilmshurst from textbook "Fast and Effective Embedded Systems Design: Applying the ARM mbed"

Who changed what in which revision?

UserRevisionLine numberNew contents of line
robt 0:2e007d983da0 1 /*Program Example 9.8: Tests reaction time, and demos use of Timer and Timeout functions
robt 0:2e007d983da0 2 */
robt 0:2e007d983da0 3 #include "mbed.h"
robt 0:2e007d983da0 4 #include <stdio.h>
robt 0:2e007d983da0 5 #include <stdlib.h> //contains rand() function
robt 0:2e007d983da0 6 void measure ();
robt 0:2e007d983da0 7 Serial pc(USBTX, USBRX);
robt 0:2e007d983da0 8 DigitalOut led1(LED1);
robt 0:2e007d983da0 9 DigitalOut led4(LED4);
robt 0:2e007d983da0 10 DigitalIn responseinput(p5); //the player hits the switch connected here to respond
robt 0:2e007d983da0 11 Timer t; //used to measure the response time
robt 0:2e007d983da0 12 Timeout action; //the Timeout used to initiate the response speed test
robt 0:2e007d983da0 13
robt 0:2e007d983da0 14 int main (){
robt 0:2e007d983da0 15 pc.printf("Reaction Time Test\n\r");
robt 0:2e007d983da0 16 pc.printf("------------------\n\r");
robt 0:2e007d983da0 17 while (1) {
robt 0:2e007d983da0 18 int r_delay; //this will be the “random” delay before the led is blinked
robt 0:2e007d983da0 19 pc.printf("New Test\n\r");
robt 0:2e007d983da0 20 led4=1; //warn that test will start
robt 0:2e007d983da0 21 wait(0.2);
robt 0:2e007d983da0 22 led4=0;
robt 0:2e007d983da0 23 r_delay = rand() % 10 + 1; // generates a pseudorandom number range 1-10
robt 0:2e007d983da0 24 pc.printf("random number is %i\n\r", r_delay); // allows test randomness;
robt 0:2e007d983da0 25 //removed for normal play
robt 0:2e007d983da0 26 action.attach(&measure,r_delay); // set up Timeout to call measure()
robt 0:2e007d983da0 27 // after random time
robt 0:2e007d983da0 28 wait(10); //test will start within this time, and we then return to it
robt 0:2e007d983da0 29 }
robt 0:2e007d983da0 30 }
robt 0:2e007d983da0 31
robt 0:2e007d983da0 32 void measure (){ // called when the led blinks, and measures response time
robt 0:2e007d983da0 33 if (responseinput ==1){ //detect cheating!
robt 0:2e007d983da0 34 pc.printf("Don't hold button down!");
robt 0:2e007d983da0 35 }
robt 0:2e007d983da0 36 else{
robt 0:2e007d983da0 37 t.start(); //start the timer
robt 0:2e007d983da0 38 led1=1; //blink the led
robt 0:2e007d983da0 39 wait(0.05);
robt 0:2e007d983da0 40 led1=0;
robt 0:2e007d983da0 41 while (responseinput==0) {
robt 0:2e007d983da0 42 //wait here for response
robt 0:2e007d983da0 43 }
robt 0:2e007d983da0 44 t.stop(); //stop the timer once response detected
robt 0:2e007d983da0 45 pc.printf("Your reaction time was %f seconds\n\r", t.read());
robt 0:2e007d983da0 46 t.reset();
robt 0:2e007d983da0 47 }
robt 0:2e007d983da0 48 }
robt 0:2e007d983da0 49