Cypress Semiconductor I2C-USB Bridge Kit Project--Windows 7 usage, working code, etc.

Specifically, Bridge Kit model Cypress Perform CY3240-I2USB Rev*A.

Working in Windows 7--Leitner's GPL Code

My earliest, unmodified copy of Leitner's ZIP file with source code and DLL--see hashes and other bibliography below.

Cypress' driver probably does not work beyond Windows XP. Leitner's code works in Windows 7--usage example below--and it doesn't need any Cypress drivers. Another advantage of his code is that there is no end-user-level installation necessary such as Cypress' usb2iic.exe.

The Bridge Kit comes with a "Slave" Demo Board with two red LEDs on it. The following C# code uses two checkboxes to turn the lights on and off with check and uncheck. This was the third driver I used to work with the board. There is probably more background when you read about the first driver--Cypress' own driver. I also wrote code that uses libUSB that works in both Linux and Windows.

Extra Control Bytes - SniffUSB

One difference between this driver and the other two is that I had to figure out some additional input bytes. Cypress has some doc on this, but I found SniffUSB very helpful with this. It allowed me to watch the USB packets to figure out what I needed to send.


SniffUSB by Thomas F. Divine of Printing Communications Associates, Inc. ("PCA" or "PCAUSA"). I was using 2.0.0006, released (most likely) February 23, 2007.

Leitner's source code comes as csharp-usb-hid-driver.zip. The DLL is USBHIDDRIVER.dll.

More on Leitner's ZIP file and Leitner

filename: csharp-usb-hid-driver.zip

SHA256(csharp-usb-hid-driver.zip)= d217cbd69a544552ca5cf1445a68585c99d52f76709441651e49027278cec04a

MD5(csharp-usb-hid-driver.zip)= 20b1df50340efe86b0af678e86229609

size = 220,962 bytes

Date of Kwynn's earliest copy = 05 (May)/11/2011 11:45 AM EDT

I believe the copy on the site was dated 2007. My file should be unmodified from what was on his site in 2011. I have no idea if it's what's there now. Now (2014/02/20) he has a downloader with a "setup.exe," so I'm avoiding that.

Leitner now goes by Florian Leitner-Fischer. Leitner's driver page.

Page(s) History (earlier)

Page History, 2014

2014/02/20 9:39pm EST - Added the ZIP file itself, hashes, Leitner's relatively new hyphenated name, and a link to his page for the driver.

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