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Circuit Description

A demonstration of the basic logic gates. Click the input switches to toggle the corresponding input value between 0 and 1, and watch the resulting behaviour. You can also use shift+click to toggle the input value between the states 0, 1, Z, and X (low, high, tri-state, undefined). The default values of the input switches are not random, but are chosen so that the first mouse-click already changes the output value of the corresponding gate.

The left column includes the non-inverting gates ('positive logic'), namely the one-input buffer, the two-input AND gate, and the two-input OR gate. The right column shows the inverting gates: inverter, NAND-gate, and NOR gate.

To explore the circuit, just click the corresponding switches, or type the following keys:

• a (buffer)
• b (inverter)
• s,d (AND2)
• f,g (NAND2)
• w,e (OR2)
• r,t (NOR2)