Xavier Gouesnard / Mbed 2 deprecated Assignment_2_XG

Test session

Dependencies:   FatFileSystem MCP23017 WattBob_TextLCD mbed

Fork of Assignment_2_herpe by Xavier Herpe

freq_task.cpp@4:48761259552a, 2017-03-14 (annotated)

Committer:
xouf2114
Date:
Tue Mar 14 14:46:43 2017 +0000
Revision:
4:48761259552a
Test of Assignment 2

Who changed what in which revision?

UserRevisionLine numberNew contents of line
xouf2114 4:48761259552a 1 /**
xouf2114 4:48761259552a 2 * Task for getting the frequency from digital input on pin13.
xouf2114 4:48761259552a 3 * The frequency is calculated by counting the number of rises
xouf2114 4:48761259552a 4 * on the pin. This is done using an interupt handler.
xouf2114 4:48761259552a 5 *
xouf2114 4:48761259552a 6 * Author: Jacob Baungard Hansen
xouf2114 4:48761259552a 7 */
xouf2114 4:48761259552a 8 #include "freq_task.h"
xouf2114 4:48761259552a 9
xouf2114 4:48761259552a 10 FrequencyTask::FrequencyTask(int starting_offset, int frequency_ms,
xouf2114 4:48761259552a 11 State * state)
xouf2114 4:48761259552a 12 : Task(starting_offset, frequency_ms) {
xouf2114 4:48761259552a 13
xouf2114 4:48761259552a 14 this->state = state;
xouf2114 4:48761259552a 15 this->count = 0;
xouf2114 4:48761259552a 16 this->interrupt = new InterruptIn(p13);
xouf2114 4:48761259552a 17
xouf2114 4:48761259552a 18 }
xouf2114 4:48761259552a 19
xouf2114 4:48761259552a 20 FrequencyTask::~FrequencyTask() {
xouf2114 4:48761259552a 21 delete this->interrupt;
xouf2114 4:48761259552a 22 }
xouf2114 4:48761259552a 23
xouf2114 4:48761259552a 24 /**
xouf2114 4:48761259552a 25 * This is called by the interupt, simply adds one to the count
xouf2114 4:48761259552a 26 */
xouf2114 4:48761259552a 27 void FrequencyTask::counter() {
xouf2114 4:48761259552a 28 this->count++;
xouf2114 4:48761259552a 29 }
xouf2114 4:48761259552a 30
xouf2114 4:48761259552a 31 void FrequencyTask::action() {
xouf2114 4:48761259552a 32 // reset the count
xouf2114 4:48761259552a 33 this->count=0;
xouf2114 4:48761259552a 34 // Enable the iterrupt
xouf2114 4:48761259552a 35 this->interrupt->rise<FrequencyTask>(this, &FrequencyTask::counter);
xouf2114 4:48761259552a 36 // wait for a specied amout of time
xouf2114 4:48761259552a 37 wait_ms(SAMPLE_LENGTH_MS);
xouf2114 4:48761259552a 38 // disable interrupts
xouf2114 4:48761259552a 39 this->interrupt->rise(NULL);
xouf2114 4:48761259552a 40 //interupt.rise<FrequencyTask>(this, NULL); This crashes, should report bug to ARM
xouf2114 4:48761259552a 41 int freq = 0;
xouf2114 4:48761259552a 42 if (this->count > 0) {
xouf2114 4:48761259552a 43 freq = count/(SAMPLE_LENGTH_MS*0.001);
xouf2114 4:48761259552a 44 }
xouf2114 4:48761259552a 45
xouf2114 4:48761259552a 46 this->state->set_freq(freq);
xouf2114 4:48761259552a 47 }