LED Signal Control
Part of the development of the model railway is the control and feedback systems. I found lots of people on YouTube designing control boards which could cope with up to two signals which were either 2 or 3 aspect signals.
I thought for my layout there’s probably a more efficient way to control signals based around the MAX7219. This chip can simultaneously control 64 LEDs which is enough for 32 two aspect signals, 21 three aspect signals or 16 four aspect signals. Of course it needn’t be signals connected to the board. It could just as easily control station lighting or other stationary LEDs on the layout. The MAX7219 takes control signals via SPI and can even be chained with another board to allow for control of 128, 192, etc. LEDs from a single microcontroller. These are the same chips used in my recent Internet Clock project.
Here’s a circuit board I’ve designed with those considerations in mind.