Truth tables of the basic gates

Objective

Apply all four input combinations to AND, OR, NAND, NOR, XOR and XNOR gates and read their truth tables on the probes.

Procedure

1. Run: the switches step through 00, 01, 10, 11 once per second; read each probe.
2. Change a switch's pattern to repeat a combination.

Theory

AND = A·B, OR = A+B, NAND = (A·B)', NOR = (A+B)', XOR = A⊕B (1 when the inputs differ), XNOR = (A⊕B)'.

Questions to answer

1. Which gate outputs 1 only when both inputs are 1?

Components used

AND, 6 × Logic probe / LED, 2 × Logic switch, NAND, NOR, OR, XNOR, XOR

About the model

Ideal wires; component models as listed in the catalogue (no parasitics, no temperature drift). Built without a breadboard so the schematic stays readable.

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