Recommendation for Logic Analyzer

[Wilson__]

Please recommend a medium-grade, nice and flexiable Logic Analyzer for debugging MCU system to Sensor at SPI signal of up to 20 MHz.  Likely, real use is 10MHz or lower.

Many thanks

[Postal2]

I'm using Kingst la1010 for debug signals up to 25MHz. Works good.
https://aliexpress.com/item/32780046572.html
Probably it was cheaper.

[mianos]

One of these is fine for SPI https://www.aliexpress.com/item/1005006004951378.html, maybe 20Mhz might be pushing it. I used one for SPI debugging for years.

I then got a dreamsourcelabs  DSLogic with 16 channels. Even better but much the same. Faster.

edit: fixed the url, sorry

[bostonman]

I'm using Kingst la1010 for debug signals up to 25MHz. Works good.

I have the LA2016 and think their product is great, so I agree with the above suggestion. My recommendation is to spend a few bucks more and get the LA5016 (newer model that wasn't out when I purchased mine), or, if you're willing to spend a few extra bucks, the LA5032.

Trying to connect sixteen channels isn't easy, and can image thirty-two would be much more challenging, but it would depend on your needs.

[DavidAlfa]

One of these is fine for SPI https://www.aliexpress.com/item/1005006004951378.html maybe 20Mhz might be pushing it.

Fixed your URL.
That a analyzer will work at 24MHz x 8ch all day long just fine.
Edit: The 16ch version can do 12MHz x16 or 24MHz x8.

[Doctorandus_P]

Those EUR5 LA's are a great way to start with LA use. In my opinion, they should be a part of each and every "arduino starters kit". I have used one for years with Sigrok / Pulseview. It's very sad and unfortunate not much work is being done on the Sigrok project anymore.

About half a year ago I bought a Kingst LA2016, because I wanted a bit more speed and channels. I verified that the software works on my Linux box (Other OS-es are apparently also supported). LA2016 also works with Sigrok/Pulseview if you install one of the latest unstable versions.

I have not yet really used my Kingst LA2016 for a project, but overall I prefer Pulseview over the original software. Pulseview has a whole lot of decoders (about 100+) and you can also write your own in Python. (those decoders are slow though).

I bought the Kingst because it was mentioned on the Sigrok site. I would love to buy officially supported hardware from Sigrok itself, but unfortunately there is none.

Bostonman suggests buying the LA5016 instead, but it's significantly more expensive. It's getting into a price range when you only buy stuff when you really need it. Even though I bought the 2016 myself, I still recommend to start with the EUR5 boxes. They cost just lunch money, and they are much more then a toy.

For sample rates, you want your LA to sample at least at 4x the data rate, but often you want more. You don't only want to capture the data, but when you want to do time measurements and delays between signals, you need a higher resolution. For example when you want to measure the propagation delay of a simple inverter, you can't do much with a LA that samples on only 100MHz. But capturing accurate data at those higher sample rates is also not trivial.

[pdenisowski]

Trying to connect sixteen channels isn't easy, and can image thirty-two would be much more challenging, but it would depend on your needs.

Yeah, keeping track of which conductor is connected to which pin is non-trivial when the conductor count gets high

[asmi]

I've heard many good things from people I trust about DreamSourceLab DSLogic U3Pro16/32 analyzers.

[bostonman]

Yeah, keeping track of which conductor is connected to which pin is non-trivial when the conductor count gets high

Keeping track of all the logic pulses too tends to get complicated too.

The only issue I've had with my LA2016 was during a recent measurement, I noticed unused (floating) channels were displaying either a constant high or pulses (I don't remember).

It was next to a desk lamp that uses florescent lights along with being next to some >38v pulses (I used voltage dividers on each line to divide the voltage in half even though the LA2016 can handle up to 50v).

I didn't dive into the issue, but sensed it was either the desk lamp or high voltages next to one another.

Otherwise, I think the unit is great and think the software does what I need it to do.

[artag]

A couple of variants of the cheap cypress-based 8 bit analysers that have appeared recently are :

https://www.ebay.co.uk/itm/194936419931
https://www.ebay.co.uk/itm/315435915307

The first is very tiny.
The second is a little bigger but appears to have some buffering or voltage translation on the front
Both have descriptions that appear to be complete rubbish. No FPGA., No ARM.

[tggzzz]

Yeah, keeping track of which conductor is connected to which pin is non-trivial when the conductor count gets high

Keeping track of all the logic pulses too tends to get complicated too.

That's why logic analysers have complex arm/trigger preconditions, plus filtering of the raw bitstreams. That enables only the interesting information to be captured/stored, while ignoring all the irrelevant signal changes. Hence it significantly reduces the need for very long buffers.

If a piece of equipment doesn't have that, then it is a bitstream recorder, not a logic analyser.

[artag]

Yeah, keeping track of which conductor is connected to which pin is non-trivial when the conductor count gets high

Yeah, don't let them take over

[jgustavoam]

I bought a Kingst LA1010. What a disappointment!
Cheap Chinese logic analyzers are better in certain situations. I do not recommend the Kingst LA1010.

[jheissjr]

https://www.hackster.io/news/raspberry-pi-pico-2-logic-analyzer-9b80800a6e16

[jheissjr]

A logic analyzer sampling at 100MHz can read a signal around 25MHz. How do you get a 25MHz signal through 4 inches / 10cm of wire on the probes? (2"/5cm for signal and 2"/5cm for ground).

[dobsonr741]

Just get a $10 or less Cypress based one for the SPI work. The search word is “USB 24MHz 8channel”. Bonus it will work with Saleae Logic2 software. Consider this as their evaluation for uour next big logic analyzer purchase.

[tggzzz]

A logic analyzer sampling at 100MHz can read a signal around 25MHz. How do you get a 25MHz signal through 4 inches / 10cm of wire on the probes? (2"/5cm for signal and 2"/5cm for ground).

How? By understanding the physics, and developing accordingly.

My 20yo Agilent 1682 gets 800MS/s through such probes. See Agilent/Keysight documentation for details.

It also has complex arm/trigger preconditions, plus filtering of the raw bitstreams running in realtime at full speed. That enables only the interesting information to be captured/stored, while ignoring all the irrelevant signal changes. Hence it significantly reduces the need for very long buffers.

If a piece of equipment doesn't have that, then it is a bitstream recorder, not a logic analyser.

For the avoidance of doubt: bitstream recorders can be useful, but are limited. It would be difficult to leave them running for 24hours waiting to capture the information that you need.

[phil from seattle]

https://www.hackster.io/news/raspberry-pi-pico-2-logic-analyzer-9b80800a6e16

Is he actually selling them these days? I tried to buy one a while ago but he had run out of the ones he had built.  Said he was going to be producing them, got on his mailing list but haven't heard boo.

[jheissjr]

I don’t know if he’s selling them. Let me know what you find and if he is.

[dave j]

I don’t know if he’s selling them. Let me know what you find and if he is.

According to the project's github page:

Finally Release 6.0 is completed and comes with many, many changes!

First, I have uploaded the project to PCBWay, I will still serve orders but as there is too much demand to keep up with it I also have uploaded it as a shared project, so you don't need to wait for me having stock. The project is found here: https://www.pcbway.com/project/shareproject/LogicAnalyzer_V6_0_cc383781.html It is right now under review so I expect it to be available in a couple of days.

Offloading producing and selling them to someone else is a sensible decision from his point of view.

[phil from seattle]

I don’t know if he’s selling them. Let me know what you find and if he is.

According to the project's github page:

Finally Release 6.0 is completed and comes with many, many changes!

First, I have uploaded the project to PCBWay, I will still serve orders but as there is too much demand to keep up with it I also have uploaded it as a shared project, so you don't need to wait for me having stock. The project is found here: https://www.pcbway.com/project/shareproject/LogicAnalyzer_V6_0_cc383781.html It is right now under review so I expect it to be available in a couple of days.

Offloading producing and selling them to someone else is a sensible decision from his point of view.

I just wanted to buy one, not go through the whole process of PCBs, ordering BOM parts, actual assembly.  Wish he did a JPCPCB project - then I could just order a few.  I might yet do the conversion my self.  I even offered to get them built and sell them for him but he wasn't interested.

[Doctorandus_P]

Elecrow also has a "Partner Products" section.
I think the idea is that you send them gerbers and and assembly info and you order them to manufacture a set amount of products and put it on their website. And then they ship it directly to your customers.

https://www.elecrow.com/cooperated-designers.html

[dave j]

I just wanted to buy one, not go through the whole process of PCBs, ordering BOM parts, actual assembly.  Wish he did a JPCPCB project - then I could just order a few.  I might yet do the conversion my self.  I even offered to get them built and sell them for him but he wasn't interested.

That's what the "PCB+Assembly" check box is for.

Whilst you can order just one, they seem to charge the same as if you want 20.

If you just want one to try the software with, it's worth remembering you can use a regular Pico - you just don't get any input level shifting/protection.