How is my Saleae Logic 8 Logic Analyzer working out?

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I received my Saleae Logic 8 analyzer in the mail a few days ago. I pre-ordered it maybe a day or two after they opened up pre-orders for their new logic analyzers earlier this year. Last I checked they haven’t started shipping the Logic Pro 8/16 yet (USB 3.0/faster). I ordered the Logic 8 as I typically use the LA for 100KHz I2c and *kbaud serial analysis. Today I used it to check some singles on a microcontroller (16F1509). I flashed the micro with some sample code to confirm it worked; it did. The LA worked just fine but I noticed something and I’m not sure if it’s an over zealous algorithm, inductance, a ghost or what? I get a lot more wiggle in the analog display in the LA app than I do on my scope. Full disclosure: my scope has not been calibrated for over two years I still trust it’s input and I use it in the 10MHz+ range all the time, seems pretty solid. This is a 100ms transition off and on. I’ll be keeping my eye on this.. naturally I checked this at max sample rate (25MHz) after I noticed this.. same wiggle.

 

The digital and analog signal shown in Saleae Logic 1.1.24 beta using a Logic 8
The digital and analog signal shown in Saleae Logic 1.1.24 beta using a Logic 8

 

The same signal (channel 0) on a 60MHz Tektronix TDS1002B scope screenshot; I trust the scopes input.
The same signal (channel 0) on a 60MHz Tektronix TDS1002B scope screenshot; I trust the scopes input.

The same signal but with the analog view in 8x mode:

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I read through the online manual but I suspect the beta software documentation is lagging behind a bit. Version 1.1.21 said there was a “New voltage measurement tool for analog”.. I see there is a .25 just out so I’ll try that. Still, regardless I have zero regrets and love this thing. I like the bigger form.. I’m also glad they have these black ground clips but wish they would make two changes.

1. Channel 0 is a black leaded wire.. like all the grounds. Maybe white or any other color?

2. In the older application the channels were color coded in the application to match their wire leads.. that was nice 🙂

.. ask and though shall receive.. I downloaded 1.1.25 and there was my voltages. Didn’t even get to draft!

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This is a great tool and a must-have if you’re doing any kind of microcontroller work. Maybe I’ll try the Logic Pro’s out once they get caught up with all the pre-orders.

2 Comments

  • September 30, 2014 - 12:54 pm | Permalink

    Hi Charles, thanks for the great write-up! I’m embarrassed to say that we’re behind pushing the calibration files for the new units and that’s why your wave isn’t quite matching the scope, and the DC value is probably a bit off as well. It’ll get cleaned up once we push those calibration files – the software will download the cal file automatically once it’s available. Sorry for the delay, should be good to go in another week.

    • Chas
      September 30, 2014 - 12:57 pm | Permalink

      Joe, you have nothing to apologize for .. this is a Beta; I get it. I have my patient-pants on. This product is a thing of beauty and you guys should be pretty darn proud of yourselves.

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