Hello, I try to supply the PLCK with 80MHz sine wave. When I click Transfer Data-In in USB control center, at the first several times, the transfers are correct. Then it will show “BULK IN transfer failed with Error Code: 997”. It does not happen when the PCLK frequency is below 50MHz (throughput: 136MB/s).

help

 Hi Lehua Chen,

Below are my answers/suggestions:

(1), Is it possible to supply PLCK with sine wave at maximum frequency (eg: 80MHz)? It seems the sine wave is the same as square wave as a clock, because only the rising edge is used.

I would recommend you to use a square wave. Square might be giving little bit more time for GPIF to sample data in.

(2), In the manural, it mentions “programmable 100-MHz GPIF II interface”. What is the maximal throughput if PCLK is 100MHz. How should we set the burstLen, dmaCfg.size and Max no. of packets in a burst?

I don't have the exact number. But GPIF II interface is well tested at 100MHz synchronous.

 burstLen, dmaCfg.size and Max no. of packets in a burst - should be same as it is described in the USBBulkSourceSink example.

(3), In the Readme.txt in USB BULK SOURCE SINK EXAMPLE, Having only 1 endpoint (IN or OUT) is recommended. So if I only want to use Endpoint In, is it necessary to delete endpoint OUT?

Yes. Comment out the code related to endpoint OUT in all the places.

I have the source files that are optimized for USBIsoSourceSink example. You can use them as a reference here.

Regards,

sai kirshna.

It seems there is some issue with attaching files....

Hello, sai Krishna,

 Hi,

Do the following things:

1. Keep only one endpoint. In your case IN endpoint.

2. #define CY_FX_EP_BURST_LENGTH          (15)     /* Super speed burst length in packets. */

3. Once you change CY_FX_EP_BURST_LENGTH, then it will be updated in the following places:

epCfg.burstLen = CY_FX_EP_BURST_LENGTH;

dmaCfg.size  = (2*1024 * CY_FX_EP_BURST_LENGTH); and 

in the descriptors, 

 /* Super speed endpoint companion descriptor for consumer EP */

    0x06,                           /* Descriptor size */

    CY_U3P_SS_EP_COMPN_DESCR,       /* SS endpoint companion descriptor type */

    (CY_FX_EP_BURST_LENGTH - 1),    /* Max no. of packets in a burst(0-15) - 0: burst 1 packet at a time */

    0x00,                           /* Max streams for bulk EP = 0 (No streams) */

    0x00,0x00                       /* Service interval for the EP : 0 for bulk */

Regards,

sai krishna.

Hi, sai Krishna,

 Hi,

Are you using Ivy bridge?. What is your host controller.

Regards,

sai krishna.

Computer:

Thanks

Lehua Chen

Hi Lehua Chen,

We are seeing some issues with Intel Ivy bridge architectures and we are working on it.

I am not sure whether your chipset is part of that.

Anyways, the best thing to do is to create a technical support case by attaching the USB trace during the error condition.

Thanks,

sai krishna.

Hi, sai Krishna,

 Hi Lehua Chen,

Did you get a chance to check the traffic on the USB bus to understand what exactly is happening.

May be the oscilloscope is not capable of probing a signal that runs at 80MHz. Please check that one as well.

Regards,

sai krishna.

Hi, sai Krishna,

Hi, sai Krishna,

Could you help me to check how the PCLK clock shape (above 80MHz) will be when your comany made the GPIF 100MHz test. Is it still perfect or there will be distortion at high frequency?

Thank you,

Lehua Chen 

Hello, sai Krishna,

When your comany made the GPIF 100MHz test, is the Streamer also used to check the throughput?

Thank you,

Lehua Chen 

Hello, sai Krishna,

When testing  the GPIF 100MHz, could we continuously transfer data (Keep SLWR always low)?

Thank you,

Lehua Chen 

Hello, sai Krishna,

When testing  the GPIF 100MHz, did you also use the evaluation board (CYUSB3KIT-001)?

Thank you,

Lehua Chen