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USB logic analyizers - current thoughts on 'the best'?

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three_jeeps:
I am looking for input regarding the 'best' options for a USB logic analyzer in the $200-$500 range 32 (34?) channels and having deep memory and at least 200 MS/s @ 32 channels.
Ive searched the forum and most of the comments/opinions seem rather sparse after 2021.  Some units I am considering are:
1 DreamSourceLab DSLogic U3Pro32
2 Intronix LA1034 LogicPort
3 Digilent Digital Discovery

The Intronix is a bit long in the tooth and doesn't have very deep memory. Reviews for the other two basically complain about software clunkyness or lack of features.  I am looking for feedback regarding these 3 or if there are any other 'newer' options out there.
Thanks
J

tverbeure:
I have the DSLogic U3Pro16, which is identical to the U3Pro32 except for the number of channels. I haven't used the Intronix or the Digital Discovery, but at some point I have looked at them.

The Intronix and the DSLogic support external clock input, but the DSLogic one can only go to 50MHz, whereas it's 200MHz for the Intronix. The Intronix seems to have much better support for state tables, features that have been present in big iron logic analyzers from HP and Tektronix since the eighties. It's not very important for me: if I really need it, I'll use my HP 1670G. The triggering options of the DSLogic are not terrible, with the option do multi-state triggering with counters etc.

BTW, the DSLogic has an external trigger input pin, with associated probe wire, but that feature is currently not implemented, and I assume it never will.

The Intronix and the Digital Discovery have a very limited set of protocol decoders. The DSLogic has a truckload, and you can use PulseView if you want even more. This is a major plus for me.

The Digital Discovery only lists input voltages up to 3.3V. The DSLogic can go much higher, including 5V which is important for me because I have old 5V based test equipment that sometimes needs debugging.

The probe wires that come with the DSLogic are excellent: they're coaxial cables with a ground pin per probe wire. I expect the DSLogic to do best in terms of probing high speed signals. The Digital Discovery uses standard 0.1" Dupont wires but for $50 you can be a high-speed probe set consists of an adapter and twisted pair data/ground cables. Not as good as coaxial, but probably sufficient.

My biggest gripe about my DSLogic is that it doesn't do analog sampling, something the Saleae Logic Pro 16 can do. But neither can the Intronix or the Digital Discovery, and Saleae priced themselves out of the hobbyist market years ago.

I've been working for a while on a DSLogic teardown and review, but it's still incomplete. But if you're interested, here's the latest draft: https://github.com/tomverbeure/tomverbeure.github.io/blob/dslogic/_drafts/2023-03-20-DSLogic-U3Pro16-Teardown.md.

tggzzz:
There's an aspect of logic analysers that is often overlooked: the desirability and ability to not capture data.

If you use the filtering and triggering capabilities of "decent" logic analysers, you can avoid seeing lots of irrelevant crap thus leading you to concentrate on the small proportion of interesting information. That has the benefit of making long capture buffers less important.

Examples:
* don't capture input except on the rising edge of an external clock. That allows you to concentrate on the digital state data (not the digitised analogue waveforms)
* don't capture input except when one input is active, e.g. a chip select. That allows you to concentrate on the data being sent to one specific chip
* don't capture input unless it occurs more than or less than a specified time after the previous data. That allows you to check for rare timing violations
* don't capture input unless it occurs after this and that and the other
Note that all those need to be executing at full input rates; postprocessing buffers inevitably means the "interesting" information will be missed because it occurred while the buffer was being processed.

metebalci:

External clock input (state-mode) is quite useful in some cases, and also sampling at both the rising and falling edges of the external clock might be useful.

I also have a Digital Discovery, but AFAIK, it does not have an external clock input.

hli:
For the Digital Discovery, the reference manual states:
Setting the voltage to 3.3V, 5V logic inputs are tolerated but the input threshold is 1.42V.
(It's hidden in a foot-note, though)

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