AnsweredAssumed Answered

BF533 - VDSP - Large Bulk USB Transfers

Question asked by GTrigity on Apr 4, 2012
Latest reply on Apr 6, 2012 by CraigG

I've recently been porting my custom application (on a custom board) on the BF533 from VDSP 4.5 to VDSP 5.0 (update 10). I finally got small (0x8 bytes) bulk command/responses to go back and forth through the Net 2272 chip that the BF533 relies on to do the USB transfers. The problem I now have is I can not get large (0x8c0 bytes) bulk transfers to work correctly from my application. I'm using DMA to do the transfers to the NET2272 chip.


When I run the BULK loopback example (from <VDSP 5 >\Blackfin\Examples\USB-LAN EZ-EXTENDER\USB\bulk_loopback_app) on my board, the maximum sized data (65k) is able to transfer back and forth without issue. The random sized data is also able to transfer back and forth without issue.


I need to get large transfers to work in both directions as some of the commands that I need to issue to the board require a lot of data to be transferred before I can move on to the next command.


Has anyone else run into an issue like this? Any suggestions would be appreciated. I know I haven't included any code, which is why I'm asking for places to look at and pitfalls that others have found that I need to look into.