RgGen Web UI
May 29, 2026 · View on GitHub
A browser-based CSR definition tool for RgGen. No server required — runs entirely in the browser.

Features
- Define register blocks, registers, and bit fields via an interactive table UI
- Supports indirect registers, array registers, and sequence bit fields
- Project-level config (bus width, address width, protocol)
- Export definitions as RgGen-compatible YAML files (bundled in a ZIP)
- Import previously exported YAML files
- State is preserved across page reloads via localStorage
Generate (ruby.wasm)
- Run RgGen in-browser via ruby.wasm — no server, no install
- Generates RTL (SystemVerilog, Verilog, Veryl, VHDL), RAL, C header, and Markdown docs
- Download all outputs as a ZIP archive
- Error messages are shown in a banner (backtrace hidden)
- When an error references a specific file and line, the offending field is highlighted:
- Config panel or block settings: the specific input is outlined in red
- Register / bit field row: the row is highlighted and the specific cell is outlined; the register is auto-expanded and scrolled into view
YAML Preview
- Preview generated YAML for config and each register block
- Line numbers displayed alongside the YAML text
- One-click copy to clipboard
Building the WASM
cd rggen-wasm
bundle install
bash bin/build.sh
cp rggen.wasm ../public/rggen.wasm
Requires ruby_wasm and a WASI-capable toolchain. See rggen-wasm/NOTES.md for details.
Copyright & License
Copyright © 2026 Taichi Ishitani. RgGen Web UI is licensed under the MIT License, see LICENSE for further details.