Sigrok and a “cheap” Saleae clone can save your life (I meant your time)

An affordable, inexpensive and “cheap” Saleae clone could save your day (really).

You could find it for less than U$ 10:
http://www.electrodragon.com/product/saleae-usb-logic-analyzer-24m-8-channel/

I was implementing a NuttX driver for BMP180 over I2C, but was failing to get it working and it was difficult to discover what was going on.

I decided to test my cheap Saleae clone for the first time. The Sigrok tool installation from source code is explained here:

http://marcusjenkins.com/linux/saleae-logic-analyser-clone-with-ubuntu/

Then compared my driver command:

bad_i2c_command

against Adrafruit BMP085/BMP180 commands:

good_i2c

Imediately I noticed I forgot to write the register address that I need to read before issuing the read command.

Just an I2C_WRITE before a I2C_READ fixed the issue!

Related: How to use sigrok to measure real-time signal latency http://blog.savoirfairelinux.com/en/2014/logic-analyzer-visualize-latency-with-sigrok-and-matplotlib/

Update: You need to copy the firmware to Sigrok work:

cp fx2lafw-saleae-logic.fw /usr/local/share/sigrok-firmware/fx2lafw-saleae-logic.fw

I got the firmware from sigrok-firmware-fx2lafw-bin-0.1.3.tar.gz

8 thoughts on “Sigrok and a “cheap” Saleae clone can save your life (I meant your time)

  1. To me, using a clone is unethical (and illegal?). Saleae does a great job developing hardware and software, and using clones like this might stop innovation. Just my $1.

    1. Hi Erich, I agree with you in part, but the equation is a little bit more complex.

      If you receive about U$5000/month then paying about U$200 for a logic analyser is fine. But if you live in a country where you receive less than U$300/month then paying U$200 + 60% import tax + U$40.00 shipping for a logic analyser is equivalent to you paying more than your month salary just for a logic analyser. (only to put it in a scale).

      Saleae is doing a great work and I’m glad to them for developing software for Windows, Linux and Mac. But instead of buying their “Apple-like design” logic analyser I bought an OpenBench (http://dangerousprototypes.com/docs/Open_Bench_Logic_Sniffer) because they are developing open-source software/hardware. As you can see OpenBench doesn’t have a case, there is no design at all, but it works better than Saleae clones (maybe even better than original Saleae).

      Buying a clone of an old product (released more than 5 years ago) will not stop innovation, what stops innovation is the company not investing their exorbitant profits in new products.

  2. Yes, I get your point. And actually I had a similar discussion a while back with students who bought clones. They did not earn $300/month, they were in the $500 range. I agree that $200 in such an environment is a lot, especially if doing it as a hobby. If it is for business, that might shift it a bit. Saleae got a lot of feedback on the price point, that’s why I think they came out with a $108 version: It is still $100, but you get a good product. The OpenBench one is then the right way to go, as this is open source and not a clone. I do not own an OpenBench one, but I hear goo things about it, especially for Linux users. And if that $50 are still too high, then it is still possible to use a FRDM-KL25Z board (for $15) as a logic analyzer (http://mcuoneclipse.com/2014/06/19/updated-freedom-board-logic-analyzer-with-dma/). It won’t work for high speed, it is not as good I think as the OpenBench one, but still good enough for many tasks.
    I don’t agree that if the clone is for an older product: to my feeling, these clones nearly have killed Saleae, and they did not come out with a new product for a long time. So buying clones regardless how old the design is will cause some damage. Again: if the price point is too high, there are plenty of alternatives to choose from. But I don’t want to give my money to pirates. I have no problem with companies going out of business because they are not competive. If a company is out of business, then making clones might be a different thing. So as long Saleae is producing and sellign Logic Analyzer, I will not consider clones.
    I hope that makes sense.

  3. Hi Erich,
    I completely agree with your discuss.
    Very nice your logic analyzer with DMA. Did you test it with Sigrok?
    I think this Saleae for $109 is only 4 inputs. It should be the original Logic with 8 inputs.
    It should be better if Saleae creates a student version like J-Link does, I bought the J-Link EDU although I prefer to use OpenOCD when microcontroller is supported or when I can adapt it to work, as for Kinetis KL25Z.

  4. I have not used Sigrok, I only have used OLS (http://www.lxtreme.nl/ols/) with it.
    Yes, that $109 has 4 inputs, but this should be enough for most applications.
    I have very mixed feelings about OpenOCD: it has not worked well for me in the past (v0.8.0), but I had not tried the latest v0.9.0 yet.

    1. Hi Erich, just to update this thread for future visitors. I bought a DreamSource DSLogic U3Pro16, it costs U$ 299 (about 4.3x less than Saleae 16 Pro) and I’m really satisfied with it. Their DSView is based on PulseView and it is really easy to use. I’ll try to get it running with PulseView to compare.

  5. If you mean design, taking a Cypress chip / reference design and calling it a logic analyzer then I can’t agree. On the other hand their software is where they’ve invested and the value is coming from. However, He is using Sigrok which isn’t made by Saleae . He’s taking a Salae clone which is pretty much just a bare bones CY7C68013A and then reflashing it so it doesn’t even have the Saleae firmware. So Cypress chip + new firmware + open source LA means he isn’t actually impinging on Saleae . The concept of using Micros and /or Cypress chips as a Logic Analyzer is also not new and not invented by Saleae .

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