Logic

One primitive: a NAND gate. Wire some together, prove the circuit against its truth table, seal it into a chip, then build the next thing out of that. Fourteen rungs later it is a processor running a program.

NOT

Report

Wire the bench up, then press Verify.

Drag a part off the rail onto the bench, or press N I O C M to drop a NAND, an input, an output, a clock or the memory under the pointer · drag from one port to another to wire them, and drag off an input port to unhook it · click an input pin to flip it, click a clock to change its level, or press T for a whole tick · click the memory part to load the program back into it · right-click a gate or a wire to delete it, or drag a box round several and press Del · Ctrl D copies the selection, wires and all, which is how you get the other three bits · double-click a chip to open it up and see the gates inside · click a row of the truth table, or a step of the sequence, to put the bench into it · Ctrl Z undoes · middle-drag or alt-drag pans, Ctrl-scroll or + - zooms, 0 fits the whole bench · F for fullscreen