FX3 device : low data rate through USB3 extension card | Cypress Semiconductor
FX3 device : low data rate through USB3 extension card
I have successfully installed a development kit for a device embedding an FX3 (actually an Enclustra MX2).
There is a sample host application based on the Cypress Bulkloop sample code, to check data tranfer and data rates.
I have strange results that needs some clarification.
[context : all hosts PCs run Win7, the tests are done with the same MX2 device and USB 3 SS cable)
-On a PC with native USB3 ports, we achieved 360 MB/s
-On another PC with a TU3-H2PIE PCI-Express card (http://www.trendnet.com/langfr/products/proddetail.asp?prod=270_TU3-H2PI...), the best we could get was 160 MB/s
-On another PC with a TU3-H2EC ExpressCard (http://www.trendnet.com/langfr/products/proddetail.asp?prod=275_TU3-H2EC...), the best we could get was also 160 MB/s
All PCs have up-to-date drivers, and the extension cards had external Power supply to ensure running at full power.
So, it seems that we cannot always guarantee > 300 MB/s data rate for the fnial customer, and it is a problem.
What is your knowledge about that kind of problem ?
-is Trendnet the culprit, for bad hardware ?
-is there some incompatibility between the FX3 and USB 3 via extension cards ?
-is there a problem in the "Bulkloop" code, which is too limited to handle specific USB interface access ?
-is there something we can do to circumvent the problem ?