Hi, I am getting started with writing programs for Adruino. I was successfully able to implement the LED-hello-world of putting together an LED, a 220 Ohm resistor on a bread board and wiring it to my UNO Q. The circuit looks like the following. [image] I have tuned on the LED for using digital…

[image] funkymonk89: using digitalWrite on both pins 6 and 9. However, analogWrite works on neither. The project is pretty simple, there's no reason why it shouldn't work. Using Wokwi it works perfectly, the LED turns on and off gradually so either you have a faulty LED or some other type of…

[image] manchuino: Please remove the pinMode line from the setup and check again. Why? The default mode for pins is "INPUT", but since we need to use it to drive a led it is an OUTPUT...

Hi @docdoc analogWrite behaves differently, and, at the moment, it doesn’t work if the pin is configured as a digital output, which pinMode(PIN, OUTPUT) does. Cheers.

[image] manchuino: analogWrite behaves differently, and, at the moment, it doesn’t work if the pin is configured as a digital output Forgive me, but I still don't understand. Are you telling me that the call to analogWrite() doesn't work if the pin is declared OUTPUT (which should be a requir…

@docdoc This is not an Uno, but Uno Q

Try the following AI generated untested sketch for UNOQ: // LED connected to pin 9 (PWM pin) void setup() { pinMode(9, OUTPUT); } void loop() { // Increase brightness from 0 to 255 for (int brightness = 0; brightness <= 255; brightness++) { analogWrite(9, brightness); // write PWM val…

Sorry, you're right, I was misled by the schematic image in the first post.

Works like a charm! Thanks manchuino!

[image] manchuino: analogWrite behaves differently, and, at the moment, it doesn’t work if the pin is configured as a digital output, which pinMode(PIN, OUTPUT) does. Just out of curiosity and to try to understand: is this a "feature" or a "bug" in the UNO Q platform/compiler? Because in my o…

analogWrite not working on PIN 6/9

Official Hardware UNO Family UNO Q

manchuino November 25, 2025, 2:56pm 3

Hey @funkymonk89

Please remove the pinMode line from the setup and check again.

Let me know!

Cheers.

Enabling PWM prevents some GPIO pins from working

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analogWrite not working on PIN 6/9

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