FABulous-fasm 0.2.0

FPGA Assembly (FASM) Parser and Generation library

This is a fork of chipsalliance/fasm, adapted for use in the FABulous flow. The original repository is no longer actively maintained.

This fork removes the ANTLR-based C++ parser that was present in the original. The original library shipped two parsers — a fast C++/ANTLR parser and a pure Python textX fallback — and would print a confusing runtime warning whenever ANTLR was not installed. Since FABulous only needs the textX parser and the ANTLR build required cmake, Java, and native libraries, the C++ parser has been removed entirely to keep installation simple and warning-free.

This repository documents the FASM file format and provides parsing libraries and simple tooling for working with FASM files using a pure Python parser based on textx.

Installation

pip install FABulous-fasm

Development

pip install -e ".[dev]"
pytest tests/

Documentation

• FASM Specification

FPGA Assembly (FASM)

FPGA Assembly is a file format designed by the F4PGA Project developers to provide a plain text file format for configuring the internals of an FPGA.

It is designed to allow FPGA place and route to not care about the actual bitstream format used on an FPGA.

Properties

• Removing a line from a FASM file leaves you with a valid FASM file.
• Allow annotation with human readable comments.
• Allow annotation with "computer readable" comments.
• Has syntactic sugar for expressing memory / lut init bits / other large arrays of data.
• Has a canonical form.
• Does not require any specific bitstream format.

Supported By

FASM is currently supported by the F4PGA Verilog to Routing fork, but we hope to get it merged upstream sometime soon.

It is also used by Project X-Ray.