The simplest dual control circuit is the downstairs / upstairs lighting control system.
2. I/O list
|LS1||X0||Light switch for upstairs|
|LS2||X1||Light switch for downstairs|
|LP1||Y0||Light for upstairs|
|LP2||Light for downstairs|
This project uses upstairs / downstairs lighting control as an example. Each switch links an input point, To make the lamp work, both switches must be in the same state: either OFF or ON.
Date: Feb 2017