Custom RISC-V Processor Powers Retro Gaming System on an FPGA
A maker has built a retro gaming system around a custom-designed RISC-V processor running on an inexpensive FPGA board.
Source: Hackaday
RISC-V, an open-source instruction set that was once mostly an academic effort, is increasingly being used in areas that would normally have gone to ARM. Some microcontrollers now run on it, and because it does not require the licensing that ARM or x86 chips do, its adoption is expected to keep growing.
The maker M_Jagadeesh97 has applied this architecture to a retro gaming system built around a custom RISC-V CPU. Since most hobbyists cannot access chip fabrication tools, the system runs on an FPGA, specifically a Terasic DE0-Nano board with 32 MB of RAM. It boots to a launcher that offers 32 games. To work within the limits of this low-power platform, the display is restricted to 64×32 pixels. That resolution keeps the aspect ratio of the original DOOM and many older games while still reaching 45 FPS.
The project write-up covers the design in depth, from bare-metal programming and CPU design to video signal timing and a Wolfenstein-style raycaster. Adding a small display appears to make the system fairly portable. The project shows how capable inexpensive FPGA boards can be with enough effort.
