Working decimal calculator. It can add one-digit numbers into two-digit numbers.
Always set only one IO source to true.
Usage:
1) Use the numpad to give the first number.
2) Press the addition key.
3) Give the second number.
4) Press the addition key again. It works now as equation mark. Wait a few seconds (on some devices it can take longer).
If you want to add more numbers:
5) Press the addition key again.
6) Give the next number to add.
7) Press the addition key.
8) Wait.
Repeat step 5-8.
The numpad (located in the bottom right corner) works the following way:
1 2 3
4 5 6
7 8 9
R 0 +
If you make a mistake use the reset button.
If you want to observe the addition, you can slow it down by increasing the capacitance of the capacitor. I don't recommend to slow down the simulation with the EveryCircuit simulation speed tool, because it slows down the relays.
The most upper relay is connected to the counter because I ran out of space, it is not required.
