fjpolo
commented
10 months ago I don't know the SMS joystick and the electrical properties of the signals, but I believe it should be possible. Bear in mind that it probably works with 5V and NESTang works with 3V3 signals, so you'd probably need a logic shifter for high frequency sampling or you'd probably do with resistor voltage dividers for sampling @60-120Hz.
My approach would be to create a new module with a clock divider from 27MHz to 60-120Hz, and just sample every pin at posedge of this clock divider, and just output that register. I think that should be enough.
I don't know how the light sensor works, so I'd just keep that disconnected
I’m no coder, more of a copy & paste warrior and have no experience of FPGA, but rather then trying to implement USB would it be possible using the GPIO of the Tango nano 20k to read the digital inputs from a Sega Master System controller? From a nostalgia perspective it’s very similar to the NES controller (rectangular pad with 2 buttons) but I think easier to read as it doesn’t use Data/Latch etc but instead each pinout is a direct connection to each button, therefore, no input lag either, unlike USB or what the BlueRetro would introduce.
I hope that makes sense and is a plausible solution 🤷🏻♂️