We suppose, for example, that all the pins of the port A are wired to the LED (this is not the case of our simulator).

We will look for the necessary instructions to turn the LED on and off.

You can operate on the mask bits (0 or 1) and on the type of operation (& or |) by simple click.

When you believe to have found the right instructions, you can execute them by clicking on the button « Execute ».

Several solutions may be right. A correct answer is proposed for every question.