Arduino UNO R3 problems with Pin 11

Libraries
1

Hey everyone

I’ve seen some issues when controlling motors using drivers with my arduino uno r3 and pin_11 specifically.

I’ve been using a TB6612FNG driver to control a DC motor for a simple project.

I use the L298N library to manage the motor driver.

I also use other components in the project, like an LCD display and an IR receiver.

One thing I found out is that I cannot connect these components to pin 11.

That is to say… if pin 11 is connected to the IR receiver for example, then the receiver does not work properly.

If I connect one of the data pins of the LCD display to pin 11 of the Arduino board, then the display becomes corrupted.

If I use any other pins except for pin_11 to connect the components , then everything works perfectly.

I’ve been discecting the L298N library code but i found nothing that points to pin 11 being used for anything.

I’m curious now to understand what makes pin 11 distinct from others in this scenario.

Thanks in advance.

2

If you are using the IRremote library, then you have to realize that the timer it uses also affects, aka blocks, other pins from sending out PWM signals (aka doing analogWrite() on them, like for example for motor control).

In the default configuration, on an Arduino Uno (ATmega328P), pins 3 and 11 become unusable for analogWrite.

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https://github.com/Arduino-IRremote/Arduino-IRremote?tab=readme-ov-file#timer-and-pin-usage

3

Thanks for the quick response.

Lil’ update:

I disconnected the IREMOTE and removed the IRremote library dependency using the LCD display only (with the LiquidCrystal library) alongside the motor.

The issue persists, pin_11 cannot be used as a data pin for the LiquidCrystal input (the display shows corrupted characters instead of the intended message).

So perhaps there’s an issue with LiquidCrystal and pin_11? Or maybe the motor driver is the issue?

4

If you only use a minimal LCD only example that uses pin 11, does it work?