gusmanb/logicanalyzer: a 24-channel, 100Msps open hardware analyzer with Sigrok decoders

What gusmanb/logicanalyzer actually is, and who it is for

This is not a single application. The repository holds Electronics, Enclosure, Firmware and Software directories, plus a wiki and a set of release packages. The hardware is a 24-channel logic analyzer rated at 100Msps, and the README describes Release 6.0 as supporting the Pico2 and solving the IO glitches of the earlier design. The target user is an embedded engineer who wants to capture SPI, I2C or UART traffic and decode it without buying a commercial instrument, and who is willing to either assemble a board or order one from PCBWay.

The README is organized as a development log rather than a manual. It opens with a note that the project was silent for a long time during a house move, then states the documentation is outdated and that the wiki will be updated. That matters for adoption: the repository gives you the artifacts, but the narrative around them is written for people who have been following along. A newcomer is told to start at the description section or read the wiki.

How the capture path works: Pico, transceivers, and Sigrok decoders

The signal chain visible in the repository is a Pico or Pico2 board feeding transceivers, with the analyzer sampling the transceiver outputs. The README states the new firmware can sample up to 400Ms/s in blast mode, and that the transceivers are rated up to 200MHz, so the design is being pushed to its limits at the top end. The author reports that at 200MHz input signals with a Pico2 at 400Ms/s, some captures show three samples of one phase and one of the other, and that the high phase is the one carrying the extra sample. The stated suspicion is either the transceivers at their maximum or residual high time on the Pico2 GPIOs.

On the software side, Release 6.0 is described as a total revamp of the analysis software, with faster rendering, autodetection of analyzers, and support for all Sigrok protocol decoders. There is also a separate TerminalCapture application, introduced so that captures are configured in a terminal UI and then triggered by pointing at a capture settings file, replacing what the README calls long inhuman command lines. The practical consequence is a two-part workflow: a capture step that produces samples, and a decode step that hands them to Sigrok decoders.

Installing LogicAnalyzer and running a first capture

The README does not give a step-by-step install procedure. It points to the Releases section for compiled projects, names Release 6.0.0.1 as the latest, and notes that an all-in-one package bundles both applications in a single zip. The TerminalCapture application is invoked with a help flag, which the README gives as the way to learn its options.

TerminalCapture --help

That command prints the available capture settings rather than performing a capture. The README's description of the workflow is that you configure the capture in the terminal application, save the settings, and then trigger a capture by specifying the capture settings file. It does not publish the exact flag name for that file, so check the output of the help command before scripting anything.

If you intend to build the hardware rather than use a prebuilt board, the release packages now include gerber files, BOMs and centroid data. The README states these were added in Release 6.0 so you can order the board from a manufacturer other than PCBWay without digging through the project directories. The current board uses 0402 components and the README states it is not intended for manual assembly, which is a real constraint if you were planning to hand-solder it.

Where LogicAnalyzer is the wrong tool

The README is candid about the limits at the top of the sample rate range. The skewed-sample behaviour at 200MHz input and 400Ms/s is described as happening at extreme speeds, with the author stating it should not affect regular use cases. That is an honest boundary, but it means you should not treat the blast mode figure as a guarantee for every capture. If your work depends on clean edges near the transceiver's rated maximum, this is not the instrument to trust without your own verification.

The second limitation is documentation. The README says the documentation is outdated and that the wiki update is pending. It also points users with questions at the Discussions section rather than a reference manual. For a team that needs to onboard someone from written docs alone, that is friction. The third is mechanical: the board is not designed for manual assembly, so the build path is a fabrication order, not a soldering session.

LogicAnalyzer compared with a Saleae-style commercial analyzer

The comparison people actually search for is against Saleae, and the difference is in where the work sits. A Saleae-style analyzer is a finished instrument with vendor software and a support path. LogicAnalyzer is a hardware design plus firmware plus a Python capture application that you assemble or order, with the README acting as a changelog. The decoder story is the closest point of contact: Release 6.0 supports all Sigrok protocol decoders, so the protocol analysis layer is not proprietary to this project.

The trade-off is control versus support. You get the schematics, the BOM, the enclosure files and the firmware, and you can order the board from PCBWay or another manufacturer using the released gerbers. You do not get a vendor who will fix a capture bug on your schedule. The README's own framing, a project that went quiet during a move and is now returning, tells you which side of that trade you are choosing.

Maintenance, releases and the GPL-3.0 licence

The last push to the default branch was on 2026-08-23, and the repository is not archived. The most recent release is v6.0.0.1 from 2025-02-09, a TerminalCapture update, following v6.0.0.0 on 2025-02-01 and v5.1.0.0 on 2024-05-05. There is also a beta 6.5 discussed in the repository's Discussions section, which the README links to for people who want to try the next version. That beta is not a release, so treat it as a moving target if you build against it.

The project is GPL-3.0. For anyone integrating the software into a product, that is a copyleft licence and the obligations are a question for your own legal review, not something this article can settle. The hardware files are in the same repository, and the README's ordering and sponsorship notes describe a single-maintainer project with a Ko-Fi account and a PCBWay shared project for board orders.

Editorial conclusion

Adopt it if you are comfortable building or ordering a board, reading a wiki that the README itself calls outdated, and driving captures from a terminal application or the Python software. Do not adopt it if you need a supported commercial probe, a documented rollback path, or a stable API surface. Before you commit, verify the Pico2 trigger behaviour and the 400Ms/s blast mode limits in the discussion threads, and check whether the beta 6.5 branch changes the capture file format you plan to parse.

Frequently asked questions

Official sources

1. gusmanb/logicanalyzer on GitHub
2. Issues
3. License: GPL-3.0
4. README
5. Releases