30 working logic-gate circuits — half adders, shift registers, multiplexers, traffic-light sequencers, and more. Each opens in the simulator with one click.
Blinker — A lamp that blinks at whatever rate you choose — with a master switch.
Button toggle — Press once to latch the lamp on, press again to release it.
D flip-flop capture — Flip the lever, press the button, and the lamp locks in the lever's value.
De Morgan demo — Two circuits, two expressions, one truth table — and two lamps that always agree.
Door toggle — A button that only works while you're holding the key.
Edge detector — A one-tick pulse every time the input changes — the trick behind every rising-edge trigger.
4-bit ripple-carry adder — Four full adders in a chain — add two nibbles and watch the carry ripple.
4-bit counter — Counts 0 through 15 on every clock tick, then wraps back to zero.
4-bit register — Four bits of storage that all latch in on the same button press.
4-bit shift register — Bits march one position to the right on every clock tick.
4-to-1 multiplexer — Four inputs, two selector bits — pick any one and send it through.
Full adder — Three bits in, a sum and a carry out — the block every adder is made of.
Half adder — Add two single bits and see the carry pop out.
Half subtractor — A minus B, with a borrow bit for when you run out of room.