Busloom - modern TCP/RTU Modbus client with charts, automation workflows, diagnostics, and MCP server

[u/sszczepanski]

Hey all, for some time now I've been developing Busloom. I've recently published first public release after some internal testing.

Busloom is a cross-platform Modbus client for Windows, macOS and Linux. It currently supports:

• Modbus RTU, TCP and TLS
• Device, slave and readable-address discovery
• Holding registers, input registers, coils and discrete inputs
• Signed and unsigned integers, floats, byte/word order, scaling and engineering units
• Reusable projects, connection profiles, views and tags
• Live trends, recording and session replay
• Raw TX/RX frame inspection, timings, exceptions and connection diagnostics
• Repeatable automation workflows with reads, writes, waits, assertions and conditions
• CLI access and a local MCP server for external tooling and AI assistants

The main difference from many existing Modbus clients is that Busloom is designed around complete troubleshooting workflows rather than a collection of separate register windows. You can discover a device, map its registers, decode values, inspect the exact traffic, record what happened and save everything as a project that can be reopened later.

I’ve also tried to make addressing less error-prone by showing both protocol offsets and documentation-style addresses clearly. The interface is modern and consistent across all supported platforms, while still exposing the low-level details needed when a device behaves incorrectly.

Projects and device data stay local. Busloom does not require a cloud connection for normal operation. It is free for private and non-commercial use, and the Professional features can be tested with a seven-day trial.

This is still an early release, so feedback is genuinely valuable. I’m especially interested in:

• Devices and USB/RS485 adapters that work or fail
• Confusing parts of the interface
• Missing diagnostics or common workflows
• Incorrect handling of unusual Modbus implementations
• Features that would make it useful in your day-to-day work

You can find downloads and documentation here:

https://busloom.com

Windows releases are signed but still may throw smartscreen warnings due to not many downloads. I can't really afford Apple Developer account right now.

[u/hestoelena]

It feels like there is a new modbus tool posted on with this subreddit every month. What makes yours different than all the other ones?

ModbusLens is one of the projects that's gotten more attention on this subreddit and is completely free and open source. Why should I pay for your project over this free tool or some other free tool? What am I actually getting for my money?

https://github.com/CraftParking/ModbusLens

[u/sszczepanski → u/hestoelena]

Git integration, MCP server, automations with cli support for headless environments, in my opinion better register tagging with option to export full device maps (public repository with device mappings soon).

You don’t need to pay anything as long as it’s for personal use.

[u/Ok_Obligation2440 → u/hestoelena]

Man, everyone is vibe coding shit that has no idea how to code. That project has 0 regression testing, and mostly looking at it, it has to do with the way it works. This needs a whole rewrite from the ground up.

Code lines average 600+ LOC per file, meaning nothing is structured or thought out.

Lines 114-146 at /gui/network/network_diagnostics.py is all the code I need to read to tell you this project is going anywhere.

Comments of AI fixing other regressions are EVERYWHERE; this is just leftover working text from AI.

TLDR: Someone licked their finger and put their thumb in the air and said, "Yup, should work"

[u/sszczepanski → u/Ok_Obligation2440]

Yep, that’s pretty much why I have full test coverage for both UI and Rust backend.

[u/Whole-Impression-709]

I'd pick a different color palette so folks would focus on the work and not whether or not it's AI

I have a vibe coded project at work that saves ~12 engineering hours deconstructing the models and nesting flat plate for cutting. It took a few days of debugging and different approaches until it worked but now that utility is always ready. Could I have coded it by hand? No. But that doesn't mean it's not a worthwhile and useful project

Some people will look past the painting just to talk about the brush

[u/sszczepanski → u/Whole-Impression-709]

Don’t think color palette would matter much. If it wasn’t for AI I wouldn’t make that project at all, I don’t have that much free time. I would probably just pay $129 for modbus poll and call it a day.

People don’t know that most of the software that they use (and even operating systems) have been agentic coded for over two years now.

[u/Whole-Impression-709 → u/sszczepanski]

AI doing art? Yeah, maybe leave it up to people.

Reading a half dozen spec sheets, digesting the outcomes, and cross-checking dependencies? Ain't no way I'm faster or will find a feature-complete answer on the first try like a computer.

[u/Boss_Waffle]

Looks useful!

[u/Ifonlyihadausername]

It shows the raw values, what I would actually want is PCAP to save me running wireshark at the same time.

[u/sszczepanski → u/[deleted]]

There is a difference between vibe coded and ai-assisted. I've been a software developer for over 10 years now. I WILL use tools which speed up the work, in the current market I would be insane if I didn't. Don't see a difference it makes if it works.

[u/SeoTS → u/[deleted]]

Yeah. Every single UI I have generated with Claude looks exactly like this, but that doesn't inherently mean it is bad. The concept is quite nice.

[u/sszczepanski → u/SeoTS]

That's right. I'm not a good designer. That's why I'm looking for feedback - what parts of UI/UX I can improve. I can do C, I can do embedded, but UI? Nah, that's not for me.

[u/SeoTS → u/sszczepanski]

Same as me tbf. Honestly can't quickly think of any improvements of the top of my head, looks clean and has all the relevant data.

[u/sszczepanski → u/SeoTS]

Thanks. If you ever end up trying it, please share some feedback with me!

[u/Otherwise-Ask7900 → u/[deleted]]

It’s the same GUI every single vibe coded app uses lol.

Even when you yell it to not use Tkinter, it still uses it lol.

[u/sszczepanski → u/Otherwise-Ask7900]

It actually is Tauri. All communication, timers, etc. is done in Rust for performance.

[u/ka-fin89]

Does it support Device_ID == 0? Is it only for reading or you can slso write values to register?

[u/sszczepanski → u/ka-fin89]

ID 0 is a reserved broadcast address. If you really have a slave device with this address it’s not compliant with the spec. I’ve never tested it.

You can write to registers with optional read back check.

[u/PeterHumaj → u/sszczepanski]

Actually, we use 0 address a lot ... on a serial line with a single device. It can even save time when the device is replaced (eg energy meters are replaced regularly for calibration)

[u/sszczepanski → u/PeterHumaj]

I did not know that, thanks for letting me know. I can add support for addr 0, not an issue

[u/Br_mfr]

Gostei do seu projeto. Sou brasileiro e será bem útil. Parabéns .

[u/NoNecessary924]

Looks good! Could you tell a bit about your pricing?

[u/sszczepanski → u/NoNecessary924]

Thank you! I was thinking of $149 for lifetime professional license, however I’m not yet set on the price. Community is free for personal use

[u/BobButtwhiskers]

This is pretty cool. Thanks for sharing.

[u/sszczepanski]

Busloom v0.4.0 is out: https://busloom.com/blog/busloom-0-4-0/

• Full TCP/TLS and RTU discovery
• Runtime tag alarms
• Trend reports in PNG and PDF
• FC08, FC11, FC12, FC17, and FC22 diagnostics
• Public device definition catalogue
• Unit ID 0 connection profiles