NOR circuit

The NOR (Not Or) function is in addition to the NAND operation the second elementary logic function. Its built into the so called NOR gates using electronic switches. This circuit shows the simplicity of the basic principles in electronic circuits. While the NAND function has two series connected transistors in parallel with the output of the LED, the NOR function has two transistors connected in parallel to the output of the LED. The NOR operation is one of the fundamental functions in electronics. The yellow LED turns OFF, when one or the other or both buttons are pressed at the same time.