I managed to decode a rotary encoder using an arduino to read the input signal but I noticed other than the interrupts, the code is mainly made up of lines similar to: "IF this AND that OR that AND that" which can be easily implemented using 74LS logic chips.
So I decided to make a circuit to do that, but I need to design something to detect the rising/falling edge of each signal. I did a bit of research but most of the recommended circuits are fairly complex so they can't be easily implemented.
Someone recommended using not gates and taking advantage of their gate delays to detect the edge but I can't come up with a good idea. If anyone has a circuit suggestion that can be easily implemented on a small PCB, I would love to hear their idea.
EDIT: I'm using a 600 Pulse per revolution optical encoder so it is noise free. It's quadrupled in software to get an effective 2400 pulses per revolution.
I DO NOT WANT TO USE AN ARDUINO FOR READING THE SIGNAL. it is easily overloaded in my application.