megan gimple / Mbed 2 deprecated gimple_A3_3_Temp_Light

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Dependencies:   mbed

main.cpp@2:38d752717527, 2021-10-27 (annotated)

Committer:
mgimple
Date:
Wed Oct 27 17:48:12 2021 +0000
Revision:
2:38d752717527
Parent:
1:d706fb07041f
Child:
3:0170897aa173
temperature reading too high ; photo cell not responsive;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mgimple 0:61f876d07ef5 1 #include "mbed.h"
mgimple 0:61f876d07ef5 2
mgimple 0:61f876d07ef5 3 Serial pc(USBTX,USBRX);
mgimple 0:61f876d07ef5 4 DigitalOut Led1(LED1);
mgimple 0:61f876d07ef5 5 DigitalOut Led2(LED2);
mgimple 0:61f876d07ef5 6 DigitalOut Led3(LED3);
mgimple 0:61f876d07ef5 7 DigitalOut Led4(LED4);
mgimple 0:61f876d07ef5 8 AnalogIn therm(p19);
mgimple 0:61f876d07ef5 9 AnalogIn light(p20);
mgimple 0:61f876d07ef5 10
mgimple 0:61f876d07ef5 11
mgimple 0:61f876d07ef5 12 float volt_raw; //raw data read from thermistor
mgimple 0:61f876d07ef5 13 float volt; //final voltage after conversion
mgimple 0:61f876d07ef5 14 float temp; //converted temperature in degrees celsius
mgimple 0:61f876d07ef5 15 float light_volt; //light voltage multiplied by 3.3 from mbed
mgimple 0:61f876d07ef5 16 float light_res; //resistance through photocell
mgimple 0:61f876d07ef5 17 float light_volt_raw; //raw voltage through photocell
mgimple 0:61f876d07ef5 18 void temp_read(); //temperature reading function
mgimple 0:61f876d07ef5 19 void light_read(); //light reading function
mgimple 2:38d752717527 20
mgimple 0:61f876d07ef5 21
mgimple 0:61f876d07ef5 22 int main()
mgimple 0:61f876d07ef5 23 {
mgimple 1:d706fb07041f 24 while(1) {
mgimple 2:38d752717527 25 temp_read();
mgimple 2:38d752717527 26
mgimple 2:38d752717527 27 light_read();
mgimple 2:38d752717527 28 }
mgimple 2:38d752717527 29 }
mgimple 0:61f876d07ef5 30
mgimple 2:38d752717527 31 void temp_read() //main temperature reading command to be called upon
mgimple 2:38d752717527 32 {
mgimple 2:38d752717527 33 volt_raw = therm.read(); //sets the raw data as a variable
mgimple 2:38d752717527 34 volt = volt_raw; //converts raw voltage to the correct scale for our mbed *3.3
mgimple 2:38d752717527 35 temp = -1481.96+sqrt(((2.1962e6)+((1.8639-volt)/(3.88e-6)))); //converts voltage to temperature
mgimple 2:38d752717527 36 pc.printf("TEMP %f Volts %3.1f Celsius \r\n",volt, temp);
mgimple 2:38d752717527 37 wait(1);
mgimple 2:38d752717527 38
mgimple 2:38d752717527 39 if (temp>=15) {
mgimple 2:38d752717527 40 Led1=1;
mgimple 2:38d752717527 41 if (temp>=20) {
mgimple 2:38d752717527 42 Led2=1;
mgimple 2:38d752717527 43 if (temp>=25) {
mgimple 2:38d752717527 44 Led3=1;
mgimple 0:61f876d07ef5 45 }
mgimple 0:61f876d07ef5 46 }
mgimple 2:38d752717527 47 }
mgimple 2:38d752717527 48 }
mgimple 0:61f876d07ef5 49
mgimple 1:d706fb07041f 50
mgimple 2:38d752717527 51 void light_read() //main light reading command to be called upon
mgimple 2:38d752717527 52 {
mgimple 2:38d752717527 53 light_volt_raw=light.read(); //sets the raw data as a variable
mgimple 2:38d752717527 54 light_res=(10000/light_volt_raw)-10000; //converting voltage to resistance
mgimple 2:38d752717527 55 light_volt=light_volt_raw*3.3; //mbed outputs 3.3 volts
mgimple 2:38d752717527 56 pc.printf("LIGHT %1.3f Voltz 6.2%f Ohms\r\n",light_volt,light_res);
mgimple 2:38d752717527 57 wait(1);
mgimple 2:38d752717527 58 if (light_volt<0.3) { //the sensor is "completely blocked" by a finger at most values under 0.3 volts. The whole photocell has to be covered however because even if a bit is showing it will read higher than 0.3
mgimple 2:38d752717527 59 Led4=1;
mgimple 0:61f876d07ef5 60 }
mgimple 2:38d752717527 61 if (light_volt>0.3) {
mgimple 2:38d752717527 62 Led4=0;
mgimple 2:38d752717527 63 }
mgimple 2:38d752717527 64 }