Helper functions in Arduino

Small named functions keep loop a one-line policy.

// Helpers keep loop readable; the compiler sees the whole sketch.
const int HEAT_PIN = 4;

float readCelsius() {
  int counts = analogRead(A2);
  return (counts * (5.0 / 1023.0) - 0.5) * 100.0;
}

void setHeater(bool on) {
  digitalWrite(HEAT_PIN, on ? HIGH : LOW);
}

void setup() {
  pinMode(HEAT_PIN, OUTPUT);
}

void loop() {
  setHeater(readCelsius() < 18.0);
  delay(1000);
}

How it works

1. readCelsius owns the TMP36 conversion arithmetic.
2. setHeater wraps the pin write behind a verb.
3. loop reads as the policy: heat when below 18 C.

Keywords and builtins used here

• HIGH
• LOW
• OUTPUT
• analogRead
• bool
• const
• delay
• digitalWrite
• float
• int
• loop
• pinMode
• readCelsius
• return
• setHeater
• setup
• void

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Step 1 of 3 in Functions & state, step 16 of 27 in Language basics.

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