With Instructables you can share what you make with the world, and tap into an ever-growing community of creative experts.
That right, you would need to have to have a flip-flop or so to latch the state at each end point if using the fan-out approach.
That's going to be a *really* big and expensive fan-out board (more likely a great big stack of boards)! Perhaps better to use a cheap micro-controller PCB at each relay or relay cluster with a cheap RS-485 interface (MAX485/487 or so) on it. Add an RS-485 interface to the arduino. Now you can assign as much address space (32-bit for 4 billion if you want that crazy) as you want, while only using 3 lines on the arduino (TX/RX/DIR). Of course, every hundred node or so, you would want to insert an RS-485 signal re-generator (2 x RS-485 driver back-to-back) . The added advantage is that the nodes can be up to several Km apart, as opposed to the PCB idea where everything needs to be in the same area.
Let your inbox help you discover our best projects, classes, and contests. Instructables will help you learn how to make anything!
© 2016 Autodesk, Inc.