[SOLVED]Millis() loop timer strange result

Projects Programming
1

The code below should produce a number range that looks like this
50
100
...
250
but the code produces
50
101
152
203
254
305
Thr question is why

int count = 0;
int tmrNow = 0;
static unsigned long tmrPrev = 0;

void setup() {
  Serial.begin(9600);
  tmrPrev = millis();
}

void loop() {
  if (millis() - tmrPrev >= 5000UL) {
    Serial.print(millis() / 1000);
    Serial.println(count);
    count++;
    tmrPrev = millis();
  }
}
2

Because there is no guarantee that when you do tmrPrev = millis(); millis won't have incremented a bit.

Try:

tmrPrev += 5000UL;
3

Only use one copy of millis per loop execution

void loop() {
  unsigned long timeNow = millis();
  if (timeNow - tmrPrev >= 5000UL) {
    Serial.print(timeNow / 1000);
    Serial.println(count);
    count++;
    tmrPrev += 5000UL;
  }
}
4

Oh stupid myself, I forgot a Serial.print()

    Serial.print(millis() / 1000);
    Serial.print(" - ");
    Serial.println(count);

Onmitting the extra print the result looks like a complete number

5

Until you add more code.

6

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