Changelog

Every release, newest first. jhdl --version tells which one you have.

0.7.0 · 28 October 2026

The first public release: free of charge, for anyone and any use, commercial work included, and you may share unchanged copies. For Windows, Linux x86-64 and 64-bit ARM Linux.

• Waveforms of any size: the viewer reads a recording a block at a time, as the screen needs it. A recording of 1.8 billion value changes (5.2 GB) opens in under four seconds, in less than a gigabyte of memory; zoomed out, it draws from summaries kept in the file, exactly as if it had read every change. VCD files of any size are read the same way.
• Why this value? Click a signal at a point in time: the processes that drive it, the signals they read, and which of them changed last, step by step back to the cause. A dataflow view, and the delta cycles of a time step (recorded by default; --wave-deltas off to leave them out).
• The wave view: a second cursor that measures time and frequency, named markers and the time between them, finding a value, analog rows, groups, rows computed from an expression of signals (valid and ready, count = 10), and saving the view as a PNG or SVG image.
• A code editor in the window: the analyzer's errors and warnings as you type, find and replace, find in files, several cursors, block (column) editing, split views of one file or two, folding.
• Projects (.jhdlproj): the sources with their libraries and VHDL versions, the top, its generics and the options, in a text file made for version control; jhdl run my.jhdlproj, or File → New project in the window. Panels can be torn off into windows of their own.
• Native code is on by default.
• Strict by default: code the standard forbids is an error, with the section of the standard and how to fix it; --compat runs it with a warning instead (the front ends in compat/ use it).
• UVVM and OSVVM are no longer built in (0.5.0 and 0.6.0 had them): install them from their projects and analyze their sources with your design.
• Projects everywhere: the code editor, Find in files and the language server analyze a project's files as the project does (libraries, VHDL versions, settings); the Run dialog takes the VHDL version, generics and compatibility mode for a file list or a VHDL file.
• Generic values on the command line as VHDL writes them: -gW=16#FF#, -gT=20ns, -gB=1, -gV=x"A5"; an error says which forms the type takes.
• Typed files (file of T) have a format of JanusHDL's own, with a header that tells a file of another type at once. Files written by earlier versions are not read; files of character stay raw bytes.
• The full user manual, as web pages and as a PDF.

Fixed:

• Ports connected to part of a signal (an element, a slice, a record field), and ports connected piece by piece, were missing from the waveforms; packages of one name in two libraries shared one scope.
• --wave together with --vcd wrote no VCD file and exited 0; --keep-going exited 0 after analysis errors. jhdl --help lists the exit codes.
• A design unit that needed one that failed to analyze got misleading follow-up errors; it now says which unit failed and where its errors are. Errors that --compat accepts no longer cascade, and the last line says so.
• The run's summary now says whether the stop time was reached or nothing was left to simulate.
• The front ends in compat/ analyze each file as the VHDL version its own command gave, and show paths as given.
• jhdlw takes its options in any order.
• A port's subtype is checked against its signal's (LRM 14.3.5), and READ of a file takes the form its type declares (LRM 5.5.2).

0.6.0 · 25 October 2026

Mostly a GUI release, for Windows and Linux (x86-64), and now also for 64-bit ARM Linux such as the Raspberry Pi 5.

• jhdlw made over: a toolbar, panels you can drag, split and rearrange (the layout is kept), a start page with your recent files and runs, a status bar that shows how the simulation stands, and the system's own file dialogs.
• Six themes: JanusHDL Dark and Light (following the system by default), One Dark, Dracula, Nord and Solarized Light.
• Simulation controls: pause and continue, run for a time, restart at time 0 (the design is analyzed again only if a source file changed), and a stop time per run.
• Waveforms show every VHDL type: records and arrays field by field (a row that opens into its parts), enumerations by name, reals, times with their unit, strings. Buses open into their bits.
• New radixes: octal, ASCII, fixed point (the binary point taken from sfixed and ufixed), floating point (half, single, double, float_pkg), Gray code and BCD.
• Faster simulation: a quicker simulation cycle, and native code (--jit on, still off by default) for much more of a testbench.
• Linux ARM64: the same programs for 64-bit ARM, tested on a Raspberry Pi 5, with native code and the window on the Pi's GPU.
• Fixed: keyboard shortcuts with Shift ran the command without it.

0.5.0 · 22 October 2026

The first preview, for Windows and Linux (x86-64).

• VHDL-1993, 2002, 2008 and 2019, with PSL assertions.
• jhdl: analyze, elaborate and run in one command, from files or a project file; an analysis cache (--cache) that keeps the warnings too.
• jhdlw: waveforms, design hierarchy and sources, and simulation runs with their output in a terminal panel.
• jhdl-lsp: the language server for editors.
• Native code for the busiest functions, --jit on; new, off by default.
• UVVM, OSVVM and VUnit testbenches run from their own sources; VUnit through the compat/ghdl and compat/nvc front ends.
• Front ends in compat/ for existing scripts: vsim, xsim, ghdl and nvc command lines.