Brendon Ky / Mbed 2 deprecated cs_335_speedometer

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Dependencies:   mbed mbed-rtos

main.cpp@14:8ceaa97cc85c, 2020-12-01 (annotated)

Committer:
bky
Date:
Tue Dec 01 09:08:37 2020 +0000
Revision:
14:8ceaa97cc85c
Parent:
13:a1a9f2282f15
Child:
16:def6abcb4294
created header file for 7 segment display driver

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bky 10:8d86e59fb408 1 # include "mbed.h"
bky 10:8d86e59fb408 2 # include "Timer.h"
bky 9:b7e8d0372f53 3
bky 10:8d86e59fb408 4 # include <time.h>
bky 10:8d86e59fb408 5 # define NUM_HOLES 32
bky 10:8d86e59fb408 6 # define CIRCUMFRENCE_CM 48.6946861
bky 9:b7e8d0372f53 7
bky 9:b7e8d0372f53 8 # define LIGHT_SENSOR_PIN p15
bky 14:8ceaa97cc85c 9 # define FLASH_THRESHOLD 0.02
bky 14:8ceaa97cc85c 10 # define PERIOD_MS 500
bky 9:b7e8d0372f53 11
bky 9:b7e8d0372f53 12
bky 9:b7e8d0372f53 13 AnalogIn lightSensorVoltage(LIGHT_SENSOR_PIN);
bky 9:b7e8d0372f53 14 Serial pc(USBTX, USBRX);
bky 0:d724bf9c4031 15
bky 9:b7e8d0372f53 16 void sendFloat(float value) {
bky 9:b7e8d0372f53 17 for (int i=0; i<4; i++)
bky 9:b7e8d0372f53 18 pc.putc(*(((char*) &value)+i));
bky 9:b7e8d0372f53 19 }
bky 9:b7e8d0372f53 20
bky 14:8ceaa97cc85c 21 void displayThread() {
bky 10:8d86e59fb408 22
bky 14:8ceaa97cc85c 23 }
bky 14:8ceaa97cc85c 24
bky 14:8ceaa97cc85c 25 int main() {
bky 14:8ceaa97cc85c 26 while(true) {
bky 14:8ceaa97cc85c 27 float minVoltage = 1.1; // voltage will never go above 1.0
bky 14:8ceaa97cc85c 28 int voltagePeaks = 0;
bky 13:a1a9f2282f15 29
bky 14:8ceaa97cc85c 30 Timer t;
bky 14:8ceaa97cc85c 31 t.start();
bky 13:a1a9f2282f15 32
bky 14:8ceaa97cc85c 33 while(t.read_ms() < PERIOD_MS) {
bky 14:8ceaa97cc85c 34 float currVoltage = lightSensorVoltage.read();
bky 14:8ceaa97cc85c 35 if(currVoltage < minVoltage) {
bky 14:8ceaa97cc85c 36 minVoltage = currVoltage;
bky 14:8ceaa97cc85c 37 } else if (currVoltage - minVoltage > FLASH_THRESHOLD) {
bky 14:8ceaa97cc85c 38 voltagePeaks++;
bky 14:8ceaa97cc85c 39 minVoltage = 1.1;
bky 14:8ceaa97cc85c 40 }
bky 14:8ceaa97cc85c 41 wait(0.01);
bky 10:8d86e59fb408 42 }
bky 13:a1a9f2282f15 43
bky 14:8ceaa97cc85c 44 t.stop();
bky 13:a1a9f2282f15 45
bky 14:8ceaa97cc85c 46 // calculate velocity
bky 14:8ceaa97cc85c 47 float velocity = (voltagePeaks * CIRCUMFRENCE_CM * 1000) / (NUM_HOLES * PERIOD_MS);
bky 13:a1a9f2282f15 48
bky 14:8ceaa97cc85c 49 //send
bky 14:8ceaa97cc85c 50 sendFloat(velocity);
bky 7:12eed49f95fc 51 }
bky 14:8ceaa97cc85c 52 return 0;
bky 10:8d86e59fb408 53 }