FX3 Isochronous bandwith issue in Linux | Cypress Semiconductor
FX3 Isochronous bandwith issue in Linux
Using cyfxisosrc example, on Windows I can easily get large bandwith above 100 MB/s but in Linux, no matter what I do, I am stuck at 8MB/s. I however use a recent version of Ubuntu which is supposed to have full support for USB3.
It seems the computer completely ignores the desciptor that changes settings such as CY_FX_ISO_BURST and CY_FX_ISO_PKTS, as altering those values has absolutely no effect on the bandwith, which is always 8MB/s.
I even tried to remove support for other speeds than Super Speed, but this had no effect.
Also, the doccumentation http://www.cypress.com/?docID=48135 is wrong, as there is nowhere a parameter CY_FX_ISOSRCSINK_DMA_ BUF_SIZE in the source code.