In this application, two 2-input NOR gates are used to create an SR latch as shown in Figure 9-1. The two additional gates can be used for a second SR latch, individually used for their logic function, or the inputs can be grounded and both channels left unused.

This device is used to drive the tamper indicator LED and provide one bit of data to the system controller. When the tamper switch outputs HIGH, the output Q becomes HIGH. This output remains HIGH until the system controller addresses the event and sends a HIGH signal to the R input which returns the Q output back to LOW.