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Logic Analyzer questions

__red____red__ Posts: 470
edited 2012-11-17 10:23 in General Discussion
Greetings,

I'm looking for opinions / advice on affordable logic analyzers. I've been stalking the USBee and Saleae.

Anyone got any insight?

Use case? Decoding i2c, uart, spi, sniffing data between embedded devices and memory :-)

Thanks,



Red
«1

Comments

  • SRLMSRLM Posts: 5,045
    edited 2011-10-13 18:47
    I'm going to buy the Logic16 from Saleae when I can afford it. They seem to have the best software available, it's new and being actively developed, and they came to the last UPEW (so they are willing to connect extra with Parallax customers).

    As for your use case, the Saleae software will automatically decode any protocol that you can specify.
  • Don MDon M Posts: 1,652
    edited 2011-10-13 18:59
    I personally own 2 of the Saleae Logic units ever since they first became available. They have proven themselves invaluable in troubleshooting and debugging. Very good value for the money. What I really like is that you can share the trace files with others collaborating on a project. All they need to do is download and install the software (free) and then they can view the whole trace.
  • davejamesdavejames Posts: 4,047
    edited 2011-10-13 20:30
    I don't believe you'll go wrong with either choice.

    I have the USBee SX and it works just fine. The software will decode "serial, two-wire serial, and SPI".

    The Saleae software looks a bit more flexible, especially in dragging data edges and placing markers.

    The SX is now about $20 more than the Logic; that bites.

    The "cool factor" of the Logic is more than the SX.

    I haven't perused the Saleae forums, and have found the USBee forums pretty vacant and sparsely answered.

    If I had the need for 8 more channels, I'd buy a Logic mainly due to the lower cost.

    *** Don M just commented that trace files can be shared amongst other Logics. The USBee SX software evidently has the same ability.
  • TorTor Posts: 2,010
    edited 2011-10-14 02:02
    The Saleae comes with a set of high-quality 'E-Z Hook XKM' microhooks, these are really nice and would cost quite a bit if bought separately. It's worth noting because there are clones out there, as well as other analyzers, where hooks are typically not included (and they don't tell you that). Or with cheaper hooks. With the Logic16 or the original Logic you're all set up, hooks and cables. Their hooks have tiny double-grippers which make them easy to use on IC pins, unlike some other single-gripper hooks I have which are trickier to use.

    -Tor
  • __red____red__ Posts: 470
    edited 2011-10-14 05:32
    I've been pondering this...

    http://www.ebay.com/itm/Oscilloscope-16ch-Logic-Analyzer-Mixed-Signal-Debugging-/230684314665?pt=LH_DefaultDomain_0&hash=item35b5db4c29

    My "conscience gene" has been throbbing as this Chinese LA claims to be functionally identical to the USBee DX.

    $180 for the equivalent $995.

    I think the throbbing is caused by my fear that this product may be a victim of the "outsource your fabrication to China and another factory in China will steal the design and undercut you".

    Ethically I'm having a hard time too thinking this as I'm making an assumption based on the reputation of the electronics industry of a country. For all I know these guys may have done the design themselves and made the hardware compatible with the USBee suite of software. There is an open source project that has done this already.
  • LeonLeon Posts: 7,620
    edited 2011-10-14 05:46
    Another option is to make your own based on the $100 Digilent Spartan-3 FPGA kit, using the sump.org LA software.
  • TorTor Posts: 2,010
    edited 2011-10-14 08:12
    __red__, I would be surprised if that ebay object is delivered with the full cable harness and hooks you'll need. They almost never do.. that's one thing which reduces the price compared to the originals they clone or copy.

    -Tor
  • davejamesdavejames Posts: 4,047
    edited 2011-10-14 08:59
    __red__ wrote: »
    My "conscience gene" has been throbbing as this Chinese LA claims to be functionally identical to the USBee DX.

    Your conscience gene has served you well, my young Padawan.

    Man! That box is a direct rip of the USBee product. They've even plagiarized USBee marketing descriptions to build their own.

    This is not the analyzer you're looking for...
  • ercoerco Posts: 20,256
    edited 2011-10-14 09:51
    Peter Anderson sells a kit to make your own logic PROBE for $2.49. Handy and has some trick functions:
    http://www.phanderson.com/logic_probe.html

    ordering: it's halfway down this page http://www.phanderson.com/picaxe

    Have a look at his home page http://www.phanderson.com He's an EE professor and has course info and lots of products for sale.
  • LeonLeon Posts: 7,620
    edited 2011-10-14 10:31
    The $30 Microchip PICkit 2 programmer/debugger can be used as a simple three-channel logic analyser. It's most useful for working with RS-232, SPI and I2C.
  • RDL2004RDL2004 Posts: 2,554
    edited 2011-10-14 11:50
    Hmm, does anybody still use logic probes these days? It's been quite a while since I used mine. I considered putting it on eBay but I didn't think I'd get much for it.
    HP545A.jpg
    1024 x 681 - 325K
  • LeonLeon Posts: 7,620
    edited 2011-10-14 12:29
    I can't find mine. :(

    It's just as easy to use the scope.
  • __red____red__ Posts: 470
    edited 2011-10-14 15:18
    davejames wrote: »

    This is not the analyzer you're looking for...

    But it's 800 dollars difference.

    I think of I buy one of the smaller usbee devices I'm just going to look at it every day and regret not having the additional functionality... I just can't justify nearly a thousand dollars...

    I'll probably just buy the logic 16 although my reasoning is pretty crappy.
  • davejamesdavejames Posts: 4,047
    edited 2011-10-14 17:09
    __red__ wrote: »
    But it's 800 dollars difference.

    Well, you now have a choice to support a (basically) counterfeit product, or the real stuff.

    Also remember "you get what you pay for". There's no telling what kind of support structure the Chinese company has...if any.

    The Logic 16 is a nice piece of kit. Go for it!
  • Paul Sr.Paul Sr. Posts: 435
    edited 2011-10-16 05:59
    Take a look at: OpenBench Logic Sniffer

    I purchased one of these not to long ago - haven't had time to get into it yet, just played around a bit, but it is a neat device with surprising power "emulates nearly all the features of an HP-16550A State/Timing Logic Analyzer"

    For $50 it's worth looking into!

    Links:
    http://gadgetfactory.net/logicsniffer/

    To Purchase:
    http://www.seeedstudio.com/depot/preorder-open-workbench-logic-sniffer-p-612.html?cPath=75

    Latest software announcement:
    http://dangerousprototypes.com/2011/06/10/openbench-logic-sniffer-release-3-08/
  • LeonLeon Posts: 7,620
    edited 2011-10-16 06:10
    It uses the same sump.org software as the FPGA-based logic analyser I mentioned earlier.
  • davejamesdavejames Posts: 4,047
    edited 2011-10-16 09:04
    Paul Sr. wrote: »
    Take a look at: OpenBench Logic Sniffer

    ...well, I have to admire their honesty:

    This open source hardware and software is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. If you can't accept this risk, please do not buy this hardware.

    :innocent:
  • Paul Sr.Paul Sr. Posts: 435
    edited 2011-10-16 10:31
    davejames wrote: »
    ...well, I have to admire their honesty:

    This open source hardware and software is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. If you can't accept this risk, please do not buy this hardware.

    :innocent:

    Don't be afraid, it's a fun place - this isn't the only one, you know!!
  • __red____red__ Posts: 470
    edited 2011-10-17 14:25
    In the interests of full disclosure, I bought the Logic 16.
    The main reasons being:
    1) Two man crew - supporting small industry.
    2) Cross platform support.
    3) I was just WAAAAYYY too confused and frustrated with the USBee product selection.
  • ctwardellctwardell Posts: 1,716
    edited 2011-10-17 14:37
    __red__ wrote: »
    In the interests of full disclosure, I bought the Logic 16.
    The main reasons being:
    1) Two man crew - supporting small industry.
    2) Cross platform support.
    3) I was just WAAAAYYY too confused and frustrated with the USBee product selection.

    Looks like a good choice. I think I'll look at getting one this winter.

    C.W.
  • AleAle Posts: 2,363
    edited 2011-10-17 22:28
    I have a pc test instruments' LogicProbe. It has 34 channels and can sample up to 500 MHz, While it has little memory, it uses compression and thus when few events are present you get 100s of us even at 100 MHz. It is not that cheap and I wish It was not tied to a PC, it has proved time and again its usefulness. A 4 channel scope can probably be very helpful, a 2 channel not that much so, I use normally both.
  • ctwardellctwardell Posts: 1,716
    edited 2012-11-11 13:12
    Paul Sr. wrote: »
    Take a look at: OpenBench Logic Sniffer

    I purchased one of these not to long ago - haven't had time to get into it yet, just played around a bit, but it is a neat device with surprising power "emulates nearly all the features of an HP-16550A State/Timing Logic Analyzer"

    For $50 it's worth looking into!

    Links:
    http://gadgetfactory.net/logicsniffer/

    To Purchase:
    http://www.seeedstudio.com/depot/preorder-open-workbench-logic-sniffer-p-612.html?cPath=75

    Latest software announcement:
    http://dangerousprototypes.com/2011/06/10/openbench-logic-sniffer-release-3-08/

    I just ordered one from epicTinker. It looks like it should be good fo debugging prop projects.

    C.W.
  • Bill HenningBill Henning Posts: 6,445
    edited 2012-11-11 14:33
    It does look very interesting... I ordered one too.
    ctwardell wrote: »
    I just ordered one from epicTinker. It looks like it should be good fo debugging prop projects.

    C.W.
  • rwgast_logicdesignrwgast_logicdesign Posts: 1,464
    edited 2012-11-12 01:24
    hmmm id love to know how it works out. ive had my eye on the scan logic 2 its cheap and has nice software. my bus pirate can use sump up to 1mhz but ive had issues getting it working. the openbench looks very appealing due to it number of channels and bandwith, but im not so sure the software is as nice as salae or scanlogic2
  • ctwardellctwardell Posts: 1,716
    edited 2012-11-12 02:10
    rwgast_logicdesign wrote: »
    hmmm id love to know how it works out. ive had my eye on the scan logic 2 its cheap and has nice software. my bus pirate can use sump up to 1mhz but ive had issues getting it working. the openbench looks very appealing due to it number of channels and bandwith, but im not so sure the software is as nice as salae or scanlogic2

    There is alternative software here: http://www.lxtreme.nl/ols/

    It is recommended here: http://dangerousprototypes.com/docs/Logic_Sniffer_quick_start_guide

    I downloaded and set it up, no device yet, so can only look and wait...

    C.W.
  • Mark_TMark_T Posts: 1,981
    edited 2012-11-12 09:40
    I'm a little surprised this thread seems not to have mentioned the PPLA: http://hackaday.com/2011/02/17/propeller-platform-logic-analzyer/
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2012-11-13 09:26
    This thread has gotten a bit long. But I keep wonder in anyone has mentioned that PropForth V5.03 has a nice working Logic Analyser as the final example in the PropForth.htm tutorials. The code is all their and ready to go. You just need to have a Propeller for a good multi-channel analyser.
  • ctwardellctwardell Posts: 1,716
    edited 2012-11-14 09:58
    Epic Tinker and the USPS kicked tail my order, ordered Sunday, Monday was Veterans Day, it still made it from California to Ohio on Wednesday!

    I had already loaded the software so install was just plugging it in on my Win7 64 box and letting it load the driver.

    I hooked up 4 channels to the /CS, SC, SO, and SI pins of the MCP23S18 on my COSMACog test setup.

    I grabbed a quick capture and used the SPI tool to analyze the data. Once I set the MSB/LSB order correctly it showed a perfect data stream.

    Lunch is over so no more time to work with it today, I'll give it a good workout this weekend.

    C.W.
  • Don MDon M Posts: 1,652
    edited 2012-11-16 18:44
    Looks like this company from China is copying the Saleae logic analyzer... cheap price.

    http://www.aliexpress.com/item/USB-Saleae-24M-8CH-Saleae-24MHz-8Channel-Logic-Analyzer-saleae-24M-8CH-Latest-support-1-1/605379977.html
  • ctwardellctwardell Posts: 1,716
    edited 2012-11-17 10:23
    Don M wrote: »
    Looks like this company from China is copying the Saleae logic analyzer... cheap price.

    http://www.aliexpress.com/item/USB-Saleae-24M-8CH-Saleae-24MHz-8Channel-Logic-Analyzer-saleae-24M-8CH-Latest-support-1-1/605379977.html

    I wouldn't want to buy one though, I really frown of such a blantant copy, even using the Saleae name.

    I really had to do some thinking before I bought the Logic Sniffer, I ended up going with it since the developers made it open source and open hardware.

    I try to steer clear of anything that is blatantly violating someones IP, if we don't honor others IP, how can we expect anyone to honor ours.

    C.W.
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