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Tuesday, April 29, 2014

Review: Scana Plus Logic Analyzer

When IkaLogic (www.ikalogic.com) offered to send me one of their Scana Plus logic analyzers, I was delighted. Not least because the software to support this USB Logic analyzer is available for Mac. So no more having to crank up a virtual machine running XP and wrestle USB drivers into submission!

Overview



The device costs €199 (at the time of writing) direct from the Ikalogic store.

An oscilloscope will often have just two channels and require a fair bit of interpretation when it comes to working out how the irregular square-wave translates into 1s and 0s and indeed how those 1s and 0s translate into messages. A Logic Analyzer is designed to capture and analyze such signals with ease.

Unboxing and Installation

When the unit arrived, I was surprised at just how compact it was. This tiny unit is capable of 100 MHz sample rate on 9 channels, with capture times only really limited by your computer's memory and disk capacity.



The box includes everything you need:

  • Scana Plus unit itself
  • USB Lead
  • 10 x test clips and cable. (9 channels + ground)
The ScanStudio software is a free download from here. If like me, you are a Mac user then you will be glad to see that the software is available for Windows, Mac and Linux. 

After installing ScanStudio, I plugged int he unit, but couldn't get it to connect. Eventually, I realized that if, like me, you are using OS X Mavericks, then you have to run a menu option from ScanStudi to install the USB driver. 



I did they, and hey presto the device connected just fine.

Using the Scana Plus

The Scana Plus uses your Mac, PC or Linux computer running a program called ScanStudio to display the waveforms captured and optionally the results of their analysis.

The example above is the data coming from a 1-wire temperature sensor (the BS18B20) connected to an Arduino Uno board.

ScanStudio has the concept of "decoders" that you can apply to the data being sampled. It comes with a number of these pre-installed into your "Library/Application Support/ScanStudio/decoders" folder (on Mac) but you can also add other decoders or even write your own in JavaScript.



You can see the results of applying the 1-Wire decoder to the data in the closeup below:



You can see that the values of the data are displayed as hex. Great for trying to work out what's going on with some thoroughly unpleasant message format.

Conclusion

While cheaper logic analyzers are available, three features of this device make it worth a few extra dollars:

  • 9 channels - many logic analyzers are 8 channel. That extra channel makes it possible to analyze an 8-bit bus with an extra clock signal.
  • For this price range you would not normally expect 100 MHz sample rate.
  • Software compatible with platforms other than Windows.
   




1 comment:

Calin Dragos said...

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Best Regards,
Dragos Calin