SPI communication from LabVIEW using FT4222

Blogs, LabVIEW Blog
I've been recently asked to help out with some SPI communication support with FTDI FT4222 device.  For those who don't have idea about this comm., it's one of the famous inter-controller communication method.  The SPI comm. speed with FT4222 can go up to 53.8Mbps.  Really, it's that much speed however you should have board designed for that much speed. Here is a short story on how I did it. I developed low-level LabVIEW drivers which essentially uses the LibFT422 DLL from FTDI.  The 4 important SPI comm., functions to be achieved are SPI Master Read SPI Master Write SPI Slave Read SPI Slave Write After writing the low-level drivers in LabVIEW, I wanted to do the real testing. But to do the real testing, I don't have access to the…
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A Poet Yearns for Realization

Blogs, Consciousness Blog
There are times too when I write some poetic words..!  This is one of the things I'm longing for in this lifetime.  Not to become poetic.!  But for other one which you can comprehend from these stanzas.  If there may shower from universe, then let that may take along.! There is good deep silence in me which I can easily feel and at the same time there is also so much of thoughts, dreams happens inside.I didn't really wanted to write down as poem, but wanted to record this state of mind written down somewhere.  However, naturally it turned out as poetic words. And here it goes... My mind is (so silent) + (so thoughtful). Unknown thoughts are coming like dream, Unknown events are coming like dream. I'm trying to…
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Running LabVIEW code through VPN Netowrks

Blogs, LabVIEW Blog
Have you ever executed a huge set of LabVIEW code which resides in other PC but you have to run them in your PC through VPN network channel?  Recently there's been a request from one of our customer to do so.!  The reason is "CONFIDANTIALITY" .  The source code can't be moved to a vendor PC and can only be accessed via their VPN. (more…)
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Recover Files Using Window’s “Previous Version” Property

Blogs, LabVIEW Blog, Other Blogs
Have you ever encountered that due to some bug in your software the imporant file has been deleted or overwritten?  May be that file could be important data logged in the production or could be your old source code.  Do you know that windows has some capabilities to recover those missed files? Recently I encountered such issue.  My own holy software which passed through all unit test cases, somehow misbehaved in the production site.  It adds more awkward moment if customer sees that issue and says "OMG..! My data are lost..!  Where is my data?". A quick google search on recovering windows files gave me a relief that Microsoft Windows in itself has some recovery given that if the restore points are configured in that Windows.  Since it's production PC,…
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Subtle Problems in Multilevel USB Hubs

Blogs, LabVIEW Blog
A project recently got me through tough times.  We have connected almost all instruments using USB and ended up using multilevel USB hubs.  The hardware connection is something like below.  We thought that everything will be fine because All of these USB ports are detected by Windows without any issues The payload of these instruments' data are very low and We're able to test all these instruments in modular level. However we faced some subtle issues which is not lucid at the beginning. (more…)
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How to use FTDI FT4222H in LabVIEW

Blogs, LabVIEW Blog
There is a very good device named FT4222H from FTDI Chip which can be used for multi-interfaces like GPIO, I2C, SPI, Interrupt.  The nicest thing is you could access all those communication protocols directly using LabVIEW.  Generally speaking, if you work with a controlling application where your end-device uses such protocols, you could use this device to communicate with the end-device and make the life easier and design would be low cost too (device costs only $2.30). [caption id="attachment_617" align="alignright" width="200"] Fig. FTDI FT4222H Device Image[/caption] GPIO Interrupt I2C Master I2C Slave SPI Master SPI Slave Initially I assumed that this device would be straight forward to use for my application which required three of those features viz.. a master I2C, a GPIO and an Interrupt.  However, it turned out…
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SVN Error – No Lock Tokens available issue

Blogs
When the SVN gives the message that no lock tokens available, then it means that the SVN server has the lock information for the file but there is no relevant client who is known as the owner of lock.  Usually this lock token issue comes up to me when I have moved the files to some other location or renamed the file. Currently I follow below steps to break the lock in SVN server Find the file which has no-lock-token using the SVN commit window. Go to the respective folder of that file and look for SVN logs and search for that file to filter the various results. Out of the results, select the top result and right click to get "Update items to the revision" for that folder. Now,…
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Data Logging and Traceable Data

Blogs, LabVIEW Blog
One of the important criteria to consider while designing the data logging is the traceability of the data in future, in relative to the device/product under test.  Some logging is required only for temporary purpose but some data are required even till the end of the device life cycle.  A traceable data is required if you think you're logging product level details and and it needs to be persistent till the death of that product. Few scenarios where you would need traceable data are... When the product is out to end customers and end customers logs you with some defects with the product, you would need to trace back what exactly happened to the product during the testing phase using the traceable data.  Or whether there is similar pattern of…
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SVN Error – Currently locked by other user

Blogs, Other Blogs
When this error happens in your Tortoise SVN Commit screen as shown below, then it means (I assume) that some time back that user had svn-locked that file and later deleted from SVN by using keep-lock in svn commit window (or in somewhere the keep-lock played badly). How to fix it then? Go to the logs of that folder in which that the file was locked as explained in error message above (in my case, I went to UserAccountAuthentication logs).  Look for the file in one of the recent revision as below, right click and choose "Browse repository". This should bring up the repo version when that file existed in repo.  In the repo browser, right click that error file and choose the "Break Lock".  This should break the lock…
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