Javier Perez / Mbed OS test_temperature_ds18b20

Test of DS18B20 Digital temperature sensor using k22f board.

Dependencies:   DS1820

main.cpp@0:6367a3d990f2, 2018-04-19 (annotated)

Committer:
javibenjas
Date:
Thu Apr 19 04:10:42 2018 +0000
Revision:
0:6367a3d990f2
initial version

Who changed what in which revision?

UserRevisionLine numberNew contents of line
javibenjas 0:6367a3d990f2 1 #include "mbed.h"
javibenjas 0:6367a3d990f2 2 #include "DS1820.h"
javibenjas 0:6367a3d990f2 3
javibenjas 0:6367a3d990f2 4 #define SLEEP_S 2
javibenjas 0:6367a3d990f2 5
javibenjas 0:6367a3d990f2 6 // I'm using DS18B20, connections
javibenjas 0:6367a3d990f2 7 // red -> 5v
javibenjas 0:6367a3d990f2 8 // blue -> GND
javibenjas 0:6367a3d990f2 9 // yellow -> D6
javibenjas 0:6367a3d990f2 10 DigitalOut led_r(LED1);
javibenjas 0:6367a3d990f2 11 DigitalOut led_g(LED2);
javibenjas 0:6367a3d990f2 12 DigitalOut led_b(LED3);
javibenjas 0:6367a3d990f2 13 DS1820 temp_probe(D6);
javibenjas 0:6367a3d990f2 14
javibenjas 0:6367a3d990f2 15 //we will use the first read as environment temperature
javibenjas 0:6367a3d990f2 16 float env_temperature = -99;
javibenjas 0:6367a3d990f2 17 // red means higher than environment
javibenjas 0:6367a3d990f2 18 // blue means cooler than environment
javibenjas 0:6367a3d990f2 19 // green means same as env
javibenjas 0:6367a3d990f2 20
javibenjas 0:6367a3d990f2 21 float read_temperature() {
javibenjas 0:6367a3d990f2 22 float tmp_temp;
javibenjas 0:6367a3d990f2 23 temp_probe.convertTemperature(true, DS1820::this_device);
javibenjas 0:6367a3d990f2 24 do {
javibenjas 0:6367a3d990f2 25 // TODO limit the n of tries
javibenjas 0:6367a3d990f2 26 // if device is not responding, will cycle forever
javibenjas 0:6367a3d990f2 27 tmp_temp = temp_probe.temperature();
javibenjas 0:6367a3d990f2 28 wait_ms(10);
javibenjas 0:6367a3d990f2 29 } while(tmp_temp == -1000);
javibenjas 0:6367a3d990f2 30 return tmp_temp;
javibenjas 0:6367a3d990f2 31 }
javibenjas 0:6367a3d990f2 32
javibenjas 0:6367a3d990f2 33 int main() {
javibenjas 0:6367a3d990f2 34 printf("Temperature probe test\r\n");
javibenjas 0:6367a3d990f2 35 float temperature = 0;
javibenjas 0:6367a3d990f2 36 temp_probe.setResolution(9); //9bits
javibenjas 0:6367a3d990f2 37
javibenjas 0:6367a3d990f2 38 //read env temperature
javibenjas 0:6367a3d990f2 39 wait(1); //wait for device to be ready
javibenjas 0:6367a3d990f2 40 env_temperature = read_temperature();
javibenjas 0:6367a3d990f2 41
javibenjas 0:6367a3d990f2 42 while(1) {
javibenjas 0:6367a3d990f2 43 temperature = read_temperature();
javibenjas 0:6367a3d990f2 44 printf("Temperature %3.1foC\r\n", temperature);
javibenjas 0:6367a3d990f2 45 if(temperature < env_temperature) {
javibenjas 0:6367a3d990f2 46 led_r = 1; // 1 is off in this board
javibenjas 0:6367a3d990f2 47 led_g = 1;
javibenjas 0:6367a3d990f2 48 led_b = 0;
javibenjas 0:6367a3d990f2 49 } else if(temperature > env_temperature) {
javibenjas 0:6367a3d990f2 50 led_r = 0;
javibenjas 0:6367a3d990f2 51 led_g = 1;
javibenjas 0:6367a3d990f2 52 led_b = 1;
javibenjas 0:6367a3d990f2 53 } else {
javibenjas 0:6367a3d990f2 54 led_r = 1;
javibenjas 0:6367a3d990f2 55 led_g = 0;
javibenjas 0:6367a3d990f2 56 led_b = 1;
javibenjas 0:6367a3d990f2 57 }
javibenjas 0:6367a3d990f2 58 // sleep
javibenjas 0:6367a3d990f2 59 wait(SLEEP_S);
javibenjas 0:6367a3d990f2 60 }
javibenjas 0:6367a3d990f2 61 }
javibenjas 0:6367a3d990f2 62