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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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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