Cypress Perform

Home > Design Support > Cypress Developer CommunityTM > Cypress Forums > USB Controllers > Question about CyU3PUsbRegisterEpEvtCallback with CYU3P_USBEP_NAK_EVT

Bookmark and Share
Cypress Developer CommunityTM
Forums | Videos | Blogs | Training | Rewards Program | Community Components



Question about CyU3PUsbRegisterEpEvtCallback with CYU3P_USBEP_NAK_EVT
Moderator:
RSKV

Post Reply
Follow this topic



Question about CyU3PUsbRegisterEpEvtCallback with CYU3P_USBEP_NAK_EVT

kommy posted on 31 Aug 2012 10:14 PM PST
Member
8 Forum Posts
Dear all, I use NRDY event callback function on USB 3.0. registered as follows. CyU3PUsbRegisterEpEvtCallback( CB_func,CYU3P_USBEP_NAK_EVT, 0x0000, 0x0008 ); // used EP3 consumer But,this NAK_EVT callback function (CB_func) is invoked more times than NRDY Transaction packet fx3 received. (I counted NRDY TP times with USB protocol analyzer and CB_func invoked times with ICE.) Is/Are there other trigger except NRDY TP invoking NAK_EVT callback? # using latest FX3 SDK (v1.2).


Re: Question about CyU3PUsbRegisterEpEvtCallback with CYU3P_USBEP_NAK_EVT

kommy posted on 31 Aug 2012 10:31 PM PST
Member
8 Forum Posts
Sorry, newlines were gone.

Re: Question about CyU3PUsbRegisterEpEvtCallback with CYU3P_USBEP_NAK_EVT

kommy posted on 04 Sep 2012 11:11 PM PST
Member
8 Forum Posts
I found a new fact. When FX3 transmits Data Packet with EoB(End of Burst) bit '1' and NRDY Transaction Packet, NAK_EVT callback function is invoked. Is it the specification of FX3 SDK ? I thought that NAK_EVT callback is invoked by only NRDY TP on USB 3.0.

Re: Question about CyU3PUsbRegisterEpEvtCallback with CYU3P_USBEP_NAK_EVT

RSKV posted on 06 Sep 2012 07:13 AM PST
Cypress Employee
655 Forum Posts

Hi Kommy,

This callback is triggered whenever the device gives an interrupt notification that an EP is not ready. How many more times you are observing the call back compared to the NRDY packets that are there on the USB bus. Is there any relevance that you observed in these numbers. One possibility could be that this callback keeps happening repeatedly from the point of an NRDY response until the endpoint becomes ready.

Thanks,

sai krishna.



Re: Question about CyU3PUsbRegisterEpEvtCallback with CYU3P_USBEP_NAK_EVT

kommy posted on 11 Sep 2012 01:14 AM PST
Member
8 Forum Posts
Hello, Sai Krishna. Thank you for replying. I don't understand this phenomenon yet. I keep to research it. Best regards.




ALL CONTENT AND MATERIALS ON THIS SITE ARE PROVIDED "AS IS". CYPRESS SEMICONDUCTOR AND ITS RESPECTIVE SUPPLIERS MAKE NO REPRESENTATIONS ABOUT THE SUITABILITY OF THESE MATERIALS FOR ANY PURPOSE AND DISCLAIM ALL WARRANTIES AND CONDITIONS WITH REGARD TO THESE MATERIALS, INCLUDING BUT NOT LIMITED TO, ALL IMPLIED WARRANTIES AND CONDITIONS OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT OF ANY THIRD PARTY INTELLECTUAL PROPERTY RIGHT. NO LICENSE, EITHER EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE, IS GRANTED BY CYPRESS SEMICONDUCTOR. USE OF THE INFORMATION ON THIS SITE MAY REQUIRE A LICENSE FROM A THIRD PARTY, OR A LICENSE FROM CYPRESS SEMICONDUCTOR.

Content on this site may contain or be subject to specific guidelines or limitations on use. All postings and use of the content on this site are subject to the Terms and Conditions of the site; third parties using this content agree to abide by any limitations or guidelines and to comply with the Terms and Conditions of this site. Cypress Semiconductor and its suppliers reserve the right to make corrections, deletions, modifications, enhancements, improvements and other changes to the content and materials, its products, programs and services at any time or to move or discontinue any content, products, programs, or services without notice.