Install icestorm with Homebrew

Project links

• Homepage
• Repository

Commands and aliases

• icebox_asc2hlc
• icebox_chipdb
• icebox_colbuf
• icebox_diff
• icebox_explain
• icebox_hlc2asc
• icebox_html
• icebox_maps
• icebox_stat
• icebox_vlog
• icebram
• icemulti
• icepack
• icepll
• iceprog
• icetime
• iceunpack

Project history

The project began as an effort to document the iCE40 bitstream format and provide simple tools for analyzing and creating bitstream files. Its own timeline records a first public release in March 2015, a working fully open-source flow with Yosys and Arachne-pnr in May 2015, and a move of the source code to GitHub in July 2015.

IceStorm's documentation frames Lattice iCE40 as a good target because the architecture is regular and minimal, with inexpensive development boards available. That made the family useful both for reverse-engineered documentation and as a reference platform for open FPGA tooling.

Adoption history

IceStorm became important because it linked several independent tools into an end-to-end flow: Yosys for synthesis, Arachne-pnr and later nextpnr for place-and-route, IceStorm tools for packing, unpacking, timing, bitstream inspection, and programming. By 2016 the documentation listed support across LP/HX 1K, 4K, and 8K package variants, and in 2018 it added iCE40 UltraPlus support.

The package shows up in Homebrew, Alpine, Fedora, and Nix metadata because FPGA hobbyists, hardware hackers, and digital-design developers often want the flow on ordinary Unix-like developer machines rather than inside vendor IDEs.

How it is used

A typical flow synthesizes Verilog with Yosys, places and routes with Arachne-pnr or nextpnr, packs the ASCII bitstream with `icepack`, and programs hardware with `iceprog`. Other tools such as `iceunpack`, `icebox_explain`, `icebox_vlog`, `icetime`, and `icepll` support reverse engineering, inspection, timing, and PLL configuration.

The package is especially associated with small iCE40 boards such as the iCEstick and HX8K breakout board, where a command-line flow is enough to build, inspect, and upload simple FPGA designs.

Why package nerds care

Project IceStorm is one of the packages that made open FPGA development feel like normal Unix development: install compiler-like tools, run commands, inspect generated artifacts, and avoid proprietary GUI-only flows for supported iCE40 parts.

It is also historically important as a bridge between software package managers and hardware toolchains. Its executables expose FPGA bitstreams as files that can be packed, unpacked, explained, converted to Verilog, timed, and programmed.

Timeline

• 2015-03-22: First public release and demonstration video.
• 2015-05-27: Working fully open-source flow with Yosys and Arachne-pnr.
• 2015-07-19: 8K chip support released and source code moved to GitHub.
• 2016-01-17: First IceTime timing-analysis release.
• 2016-02-07: Support for all package variants of LP1K, LP4K, LP8K, HX1K, HX4K, and HX8K.
• 2018-01-30: iCE40 UltraPlus support released.
• 2025: The GitHub repository lists v1.1 as a tagged release.

Related projects

• Yosys provides Verilog synthesis for the iCE40 flow.
• Arachne-pnr and nextpnr provide place-and-route options used with IceStorm.
• Lattice iCEcube2 is the proprietary tool whose generated bitstreams were used as comparison material during reverse engineering.
• F4PGA and other FPGA documentation efforts belong to the broader open FPGA tooling movement.

Sources

• https://formulae.brew.sh/formula/icestorm
• https://github.com/YosysHQ/icestorm
• https://github.com/YosysHQ/icestorm/releases
• https://prjicestorm.readthedocs.io/en/latest/overview.html