n00b question about gaming project

[vivi-d]

Quick question... I'm thinking of developing a small device that could be an "adaptor" between gaming controllers. The idea would be to (thru USB?) make it possible to use a PS4 controller on xbox. Or vice versa.

About how many lines of VHDL programming would a project like this need? Would it be a good beginner project?

[ataradov]

This is more of a microcontroller project than an FPGA project. USB on FPGA is likely to require an MCU core anyway.

First order of business would be to figure out what protocols they are using and if they are documented anywhere.

[SiliconWizard]

First, I would suppose both are HID devices.
I don't have a Xbox but I do have a PS4, and I just checked connecting one controller via USB to a PC. The controller shows up as "Sony Corp. DualShock 4" and can be used as a regular joystick.

Not sure about the Xbox, but I suspect this is the same. So if that's the case (which is likely), it will mostly be a matter of matching controls from one controller to the other.
This could be done with a MCU of course, but you'd need one with two USB OTG controllers, one programmed as host and the other as device.

IIRC (although i've never tested myself), RPi's can be used as USB devices on one of their USB ports. If that's indeed the case (someone here may have more info/already done that), then this would probably be the easiest path for what you want to achieve.

[asmi]

Yeah, USB is a very "software-heavy" protocol as it heavily relies on a software driver stack, which is what made it so successful because adding/changing software is always easier than modifying hardware, especially when it comes to adding support for new features to existing hardware.
But the flip side is that basically requires some sort of CPU to actually run that software stack, unlike some other protocols which can be implemented in pure hardware, or mostly in hardware.

[dobsonr741]

Done already on MCU: https://github.com/jfedor2/hid-remapper