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@luiszugasti
Last active Jul 12, 2020
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A sample, asynchronous collector of MQ-* data. Expect to find it here when it goes public: https://github.com/luiszugasti/air_sens
#include <Arduino.h>
int mq2 = A2;
int mq4 = A3;
int mq5 = A4;
int mq135 = A5;
int incomingByte;
void setup() {
pinMode(mq2, INPUT);
pinMode(mq4, INPUT);
pinMode(mq5, INPUT);
pinMode(mq135, INPUT);
Serial.begin(9600);
}
/* valuePrint prints the value for this label.
* Creates side effects only.
*/
void valuePrint(String label, int reading) {
Serial.print(label);
Serial.print("=");
Serial.print(reading);
}
void loop() {
// see if there's incoming serial data:
if (Serial.available() > 0) {
// read the oldest byte in the serial buffer:
// "When you call Serial.read a byte is removed from the receive buffer and returned to your code"
incomingByte = Serial.read();
// if it's a capital H (ASCII 72), read the values and send them to the raspberry host.
// TODO: ensure the message is always the same length, each time
if (incomingByte == 72) {
int mq2Reading = analogRead(mq2);
int mq4Reading = analogRead(mq4);
int mq5Reading = analogRead(mq5);
int mq135Reading = analogRead(mq135);
Serial.print("?");
valuePrint("mq2", mq2Reading);
Serial.print("&");
valuePrint("mq4", mq4Reading);
Serial.print("&");
valuePrint("mq5", mq5Reading);
Serial.print("&");
valuePrint("mq135", mq135Reading);
Serial.print("\n");
}
}
// read the serial only every second
delay(1000);
}
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