Bits, Bytes, and Gates
Notes on portable stimulus, hardware modeling, and Python in design verification.
PSS 3.1: Simplifying Composition
A PSS description is structure, in much the same way that hardware is structural. Even PSS activities are visualized as UML diagrams -- which have a certain structure to them. The next category of features to look at in PSS 3.1 are features that help to simpli…
PSS 3.1: Simplifying Constraint Modeling
PSS language constructs fall into two main categories: declarative and procedural. When you see 'declarative', think 'rules' and 'constraints'. A declarative description is captured in terms of boundaries and relationships that must hold for the description …
PSS 3.1 Is Out for Public Review -- Here's What Changed
After roughly two years of work, the Accellera Portable Stimulus Working Group (PSWG) released PSS 3.1 for public review. PSS 3.1 is a so-called 'minor' release, which is always a bit subjective. PSS 3.1 doesn't introduce major new features, the way that PSS …
The Right Skills for the Job: Project-Scoped Agent Skills
Agentic AI has quickly become a dominant workflow. Give an LLM access to the filesystem and shell, provide it good instructions, and watch it work! It's that second part that is critical to making the process scalable. LLMs are quite happy to fill in the gaps…
What's My Env Again?
Almost any non-trivial project will require some amount of environment configuration. Perhaps the project uses a local Python virtual environment that must be used for running tests. Perhaps it's a hardware-design project that needs to configure the environmen…
Simplifying Access to Open-Source EDA Software
Free and Open-Source Silicon (FOSSi) hardware designs face an interesting challenge. There's a sizable and growing set of open source tools. But, obtaining the software in pre-built form -- especially the latest versions -- can be a challenge due to the numbe…
Managing DV Project Dependencies - Now with FuseSoc
I had the pleasure of attending [LatchUp](https://fossi-foundation.org/latch-up/2026) this past weekend. Conferences invariably spark new ideas and new perspectives, and this past weekend was no different. Specifically, I found a new perspective on interope…
Better Coverage Analysis with AI
One near-term outcome of AI's [impact on open source EDA](https://bitsbytesgates.com/eda/2026/02/07/OpenSourceEDAinAIEra.html) is that I've been revisiting and enhancing some of my older projects. [PyUCIS](https://fvutils.github.io/pyucis/), a set of tools fo…
Open Source EDA in the AI Era
AI is changing the world in many ways. This is particularly visible in the commercial software-development space, where AI is often credited with [developing significant portions of new code](https://techcrunch.com/2025/04/29/microsoft-ceo-says-up-to-30-of-t…
Getting Started with Executable Specs
Hardware engineers spend their lives working with specifications, both natual language ("paper") and executable. We've been looking at characterizing the interfaces and internal implementation of executable specifications -- models. But, enough theory. Let's …