Using the Logisim Simulator

Updated 2014.09.15

You will use the following in the circuits that you build.

Input switches:

          On the toolbar it looks like this:   

          On the grid it looks like this:        

The switch toggles between 1 (bright green) and 0 (dark green). Connect the switch to any input connectors that you need for input. Note that this can be a multi-bit input!

Output LED:

          On the toolbar it looks like this:   

               On the grid it looks like this:        

Connect the output line from your circuit to this. Turns dark green when a 0 is output, bright green when a 1 is output. If it is blue or gray, it means that not everything has been connected properly.


Step 1: Select your components from the toolbar by clicking on the component on the toolbar and then clicking on the grid where you want the component to be placed.

The above circuit has

·       Two input switches

·       An AND gate,

·       An output LED to see the output of the circuit.


Step 2: Make your connections by dragging from one connection point to another.


Step 3: Add labels using the label tool:


Step 3: Test your circuit

The circuit is done! Now try all possible combinations of input switches (A and B) by using the “poke” (hand) tool to toggle the input values:

·       A=0, B=0, output=0


·       A=1, B=0, output=0

·       A=0, B=1, output=0

·       A=1, B=1, output=1