megan gimple / Mbed 2 deprecated gimple_A3_3_Temp_Light

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Dependencies:   mbed

main.cpp@3:0170897aa173, 2021-10-29 (annotated)

Committer:
mgimple
Date:
Fri Oct 29 14:52:42 2021 +0000
Revision:
3:0170897aa173
Parent:
2:38d752717527 
photocell working ; final version

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mgimple 0:61f876d07ef5 1 #include "mbed.h"
mgimple 3:0170897aa173 2 #include "math.h"
mgimple 0:61f876d07ef5 3
mgimple 0:61f876d07ef5 4 Serial pc(USBTX,USBRX);
mgimple 0:61f876d07ef5 5 DigitalOut Led1(LED1);
mgimple 0:61f876d07ef5 6 DigitalOut Led2(LED2);
mgimple 0:61f876d07ef5 7 DigitalOut Led3(LED3);
mgimple 0:61f876d07ef5 8 DigitalOut Led4(LED4);
mgimple 0:61f876d07ef5 9 AnalogIn therm(p19);
mgimple 0:61f876d07ef5 10 AnalogIn light(p20);
mgimple 0:61f876d07ef5 11
mgimple 0:61f876d07ef5 12
mgimple 0:61f876d07ef5 13 float volt_raw; //raw data read from thermistor
mgimple 0:61f876d07ef5 14 float volt; //final voltage after conversion
mgimple 0:61f876d07ef5 15 float temp; //converted temperature in degrees celsius
mgimple 0:61f876d07ef5 16 float light_volt; //light voltage multiplied by 3.3 from mbed
mgimple 0:61f876d07ef5 17 float light_res; //resistance through photocell
mgimple 0:61f876d07ef5 18 float light_volt_raw; //raw voltage through photocell
mgimple 2:38d752717527 19
mgimple 0:61f876d07ef5 20
mgimple 0:61f876d07ef5 21 int main()
mgimple 0:61f876d07ef5 22 {
mgimple 1:d706fb07041f 23 while(1) {
mgimple 3:0170897aa173 24 volt_raw = therm.read(); //sets the raw data as a variable
mgimple 3:0170897aa173 25 volt = volt_raw*3.3; //converts raw voltage to the correct scale
mgimple 3:0170897aa173 26 float temp = (-1481.96)+ sqrt((2.1962*(powf(10,6)))+((1.8639-volt)/(3.88*(powf(10,-6))))); //converts voltage to temperature
mgimple 3:0170897aa173 27 pc.printf("Thermocell Voltage: %f V\r\n",volt);
mgimple 3:0170897aa173 28 pc.printf("Temperature: %f C\r\n",temp);
mgimple 0:61f876d07ef5 29
mgimple 3:0170897aa173 30 if (temp>=15 && temp<20) {
mgimple 3:0170897aa173 31 Led1=1;
mgimple 3:0170897aa173 32 }
mgimple 3:0170897aa173 33 if (temp<15 && temp>=20) {
mgimple 3:0170897aa173 34 Led2=1;
mgimple 3:0170897aa173 35 }
mgimple 3:0170897aa173 36 if (temp>=25) {
mgimple 3:0170897aa173 37 Led3=1;
mgimple 3:0170897aa173 38 }
mgimple 3:0170897aa173 39
mgimple 2:38d752717527 40
mgimple 3:0170897aa173 41 light_volt_raw=light.read(); //sets the raw data as a variable
mgimple 3:0170897aa173 42 light_res=(10000/light_volt_raw)-10000;
mgimple 3:0170897aa173 43 light_volt=light_volt_raw*3.3;
mgimple 3:0170897aa173 44 pc.printf("Photocell Resistance: %f Ohms\r\n",light_res);
mgimple 3:0170897aa173 45 pc.printf("Photocell Voltage: %f \r\n",light_volt);
mgimple 3:0170897aa173 46 if (light_volt<1.55) { //the sensor is "completely blocked" by a finger at most values under 0.3 volts
mgimple 3:0170897aa173 47 Led4=1;
mgimple 3:0170897aa173 48 }
mgimple 3:0170897aa173 49 if (light_volt>1.55) {
mgimple 3:0170897aa173 50 Led4=0;
mgimple 0:61f876d07ef5 51 }
mgimple 2:38d752717527 52 }
mgimple 3:0170897aa173 53 }