Kevin Hetterscheid / EMG

emg

Fork of EMG by Tom Tom

main.cpp@4:8b298dfada81, 2013-10-02 (annotated)

Committer:
vsluiter
Date:
Wed Oct 02 09:40:41 2013 +0000
Revision:
4:8b298dfada81
Parent:
3:1296e996026a
Child:
5:4dacb7b72109
Added comments

Who changed what in which revision?

UserRevisionLine numberNew contents of line
vsluiter 0:32bb76391d89 1 #include "mbed.h"
vsluiter 0:32bb76391d89 2
vsluiter 4:8b298dfada81 3 //Define objects
ArvidKeemink 1:db54d9412d18 4 AnalogIn emg0(PTB0); //Analog input
ArvidKeemink 1:db54d9412d18 5 PwmOut red(LED_RED); //PWM output
vsluiter 2:e314bb3b2d99 6 Ticker timer;
vsluiter 2:e314bb3b2d99 7 Serial pc(USBTX,USBRX);
vsluiter 2:e314bb3b2d99 8
vsluiter 4:8b298dfada81 9 /** Looper function
vsluiter 4:8b298dfada81 10 * functions used for Ticker and Timeout should be of type void <name>(void)
vsluiter 4:8b298dfada81 11 * i.e. no input arguments, no output arguments.
vsluiter 4:8b298dfada81 12 * if you want to change a variable that you use in other places (for example in main)
vsluiter 4:8b298dfada81 13 * you will have to make that variable global in order to be able to reach it both from
vsluiter 4:8b298dfada81 14 * the function called at interrupt time, and in the main function.
vsluiter 4:8b298dfada81 15 * To make a variable global, define it under the includes.
vsluiter 4:8b298dfada81 16 * variables that are changed in the interrupt routine (written to) should be made
vsluiter 4:8b298dfada81 17 * 'volatile' to let the compiler know that those values may change outside the current context.
vsluiter 4:8b298dfada81 18 * i.e.: "volatile float emg_value;" instead of "float emg_value"
vsluiter 4:8b298dfada81 19 * in the example below, the variable is not re-used in the main function, and is thus declared
vsluiter 4:8b298dfada81 20 * local in the looper function only.
vsluiter 4:8b298dfada81 21 **/
vsluiter 2:e314bb3b2d99 22 void looper()
vsluiter 2:e314bb3b2d99 23 {
vsluiter 4:8b298dfada81 24 /*variable to store value in*/
vsluiter 4:8b298dfada81 25 float emg_value;
vsluiter 4:8b298dfada81 26 /*put raw emg value both in red and in emg_value*/
vsluiter 4:8b298dfada81 27 red = emg_value = emg0.read();
vsluiter 4:8b298dfada81 28 /*send value to PC. use 6 digits precision*/
vsluiter 4:8b298dfada81 29 pc.printf("%.6f\n",emg_value);
vsluiter 2:e314bb3b2d99 30 }
vsluiter 0:32bb76391d89 31
vsluiter 0:32bb76391d89 32 int main()
vsluiter 0:32bb76391d89 33 {
vsluiter 4:8b298dfada81 34 /*setup baudrate. Choose the same in your program on PC side*/
vsluiter 2:e314bb3b2d99 35 pc.baud(115200);
vsluiter 4:8b298dfada81 36 /*set the period for the PWM to the red LED*/
vsluiter 2:e314bb3b2d99 37 red.period_ms(2);
vsluiter 4:8b298dfada81 38 /**Here you attach the 'void looper(void)' function to the Ticker object
vsluiter 4:8b298dfada81 39 * The looper() function will be called every 0.001 seconds.
vsluiter 4:8b298dfada81 40 * Please mind that the parentheses after looper are omitted when using attach.
vsluiter 4:8b298dfada81 41 */
vsluiter 2:e314bb3b2d99 42 timer.attach(looper, 0.001);
ArvidKeemink 1:db54d9412d18 43 while(1) //Loop
vsluiter 0:32bb76391d89 44 {
vsluiter 4:8b298dfada81 45 /*Empty!*/
vsluiter 4:8b298dfada81 46 /*Everything is handled by the interrupt routine now!*/
vsluiter 0:32bb76391d89 47 }
vsluiter 0:32bb76391d89 48 }