Doing arithmitics on macro definitions throws an error

Projects Programming
7

No, most of the time the compiler is smart, it will see it can inject the value right where you use it. (using const is key though)

compile this

#include <Wire.h>

void setup() {
  for (byte i = 0; i < 5; i++) {
    Wire.beginTransmission(0x53);
    Wire.write(0xC0 + i);     Wire.write(0x0D);     Wire.write(0x00);
    Wire.endTransmission(false);
  }
}

void loop() {}

or this

#include <Wire.h>
const byte i2cadd = 0xC0;

void setup() {
  for (byte i = 0; i < 5; i++) {
    Wire.beginTransmission(0x53);
    Wire.write(i2cadd + i);     Wire.write(0x0D);     Wire.write(0x00);
    Wire.endTransmission(false);
  }
}

void loop() {}

you should see the same SRAM and flash usage

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