Compact USB HID host FPGA core

nand2mario, 8/2023

Usb_hid_host is a compact FPGA core designed to support USB keyboards, mice and gamepads. It is designed mainly for FPGA retro gaming and computing projects. The most significant advantage is its all-in-one design. It does not require a CPU to work. And it is quite small (<300 LUTs, <250 registers and 1 BRAM block).

To use usb_hid_host, simply add usb_hid_host.v, usb_hid_host_rom.v and usb_hid_host_rom.hex to your project. The module interface in usb_hid_host.v should be sufficiently documented to get you started.

For FPGA boards with pmod ports, usb_host_pmod is a pmod module designed to work with usb_hid_host.

Please refer to usb_hid_host.md for a more comprehensive introduction to the design of the core.

Sample projects

Sample projects are available for the following boards to demonstrate the usage of usb_hid_host.

• Tang Nano 20K (Gowin GW2A FPGA). Gowin IDE project file usb_hid_proj.gprj is provided. Simply open it in Gowin IDE and build the project.
• IceSugar-Pro and Machdyne Schoko (Lattice ECP5). These come with Makefiles for the open source Yosys/nextpnr toolchain.
• iCEBreaker and Machdyne Riegel (Lattice iCE40), also building with Yosys/nextpnr.

Connect your USB devices and expect results similar to the following.

Usb_hid_host does not rely on vendor-specific primitives, making it compatible with most FPGAs and boards. If you encounter any problems, please submit an issue.

For a larger project using usb_hid_host, see NESTang.

Improvements under consideration

• Better compatibility for low-speed gamepads through VID/PID identification.
• Support XBOX360-compatible controllers (needs USB full-speed).
• Support USB hubs (also needs USB full-speed).
• Support MIDI devices.

Credit

• Based on hi631's project supporting USB gamepad on Tang Nano 9K.