I write a firmware for a system based on FX3 and videosensor. I programmed GPIF as described in AN75779 and created DMA chanel for translate data to the PC. I didn't make changes in data, only translate.

As described in AN75779, I define the size of DMA bufer as 16kB, and the bufer count as 4. But when I try to translate data it translate only few frames, and then translation terminated and device didn't detect by Cypress CC.

I reduced the size of DMA bufer to 1kB.  Now traslate didn't terminat, but the data arrived discordantly, so i can't capture properly image.

Where there is may be a problem and how solve it?

How do you debug it? You may want to add some print messages to the firmware and see what exactly is happening?

Function CyU3PDmaMultiChannelCommitBuffer returns CY_U3P_ERROR_INVALID_SEQUENCE and translation terminated. What this mean I don't understand because there aren't any description in technical documentations.  Also device don't detects by Cypress CC, but in system device manager it is present.

When I use the small bufer device don't returns any errors.

I solved the problem with transfer data. But now there is another problem with the low data transfer speed. If I've transfer less then 10MB/s there are all ok, and packets havn't lost. But when I have increased data trasfer speed to 50MB/s many packets become lost.

I when I try to test the speed with USBBulkSourceSink example it was up to 380MB/s. But when I use data from videosensor to transfer in this exapmple it transefr with loses. What may be cause of this lases.

Try using the maximum dma buffer that is available.

Regards,

sai krishna.