Implementing RISC-V in an FPGA
All the source code, processor hardware design intellectual property, and development tools required to build and implement a complete RISC-V processor in a low-cost FPGA are freely available on the internet. This section provides a high-level overview of the open-source RISC-V design and the steps for bringing it up in an FPGA device. The total cost for the hardware to accomplish this task is less than US$200.
The RISC-V FPGA target in this example is the Digilent Arty A7-35T board, available at https://store.digilentinc.com/arty-a7-artix-7-fpga-development-board-for-makers-and-hobbyists/. The Arty A7-35T costs US$129 at the time of writing.
The Arty A7-35T contains a Xilinx Artix-7 XC7A35TICSG324-1L FPGA, which can be programmed to implement a RISC-V processor. The XC7A35TICSG324-1L has the following features:
- 5,200 logic slices.
- 1,600 of the logic slices can implement a 64-bit RAM.
- 41,600 flip-flops. Each logic slice...
