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LED is on for LOW, off for HIGH, opposite to expected

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#29 2 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
arduino, cpp
Domain
embedded-iot

Research direction

Start with the shown Blink sketch and the D1 mini onboard LED behavior, then check the repository's related example or board documentation. Confirm whether the active-low result is expected and whether the example's comments or pin guidance need correction; done means the expected LED behavior is clearly established.

Written by the indexing model from the issue text.

Description

This sketch is the basic "blink" example from this repository with a longer time LOW so as to see the difference between LOW and HIGH. LED is on for 4 sec, off for 1 sec. Other tests confirm that LOW=On and HIGH=Off. Is this normal or have I done something wrong during the very complex setup process? Does this mean that my other pins are reversed?

/*

  • WEMOS sample sketch modified with my long time off to check
  • Blink
  • Turns on the onboard LED on for one second, then off for FOUR seconds, repeatedly.
  • This uses delay() to pause between LED toggles.
    */

void setup() {
pinMode(BUILTIN_LED, OUTPUT); // initialize onboard LED as output
}

void loop() {
digitalWrite(BUILTIN_LED, HIGH); // turn on LED with voltage HIGH
delay(1000); // wait one second
digitalWrite(BUILTIN_LED, LOW); // turn off LED with voltage LOW
delay(4000); // wait FOUR seconds
}

Dominant language
C++
Stars
560
Forks
226
PR merge metrics
No merged PRs in 30d

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