Cypress Perform

Home > Design Support > Cypress Developer CommunityTM > Cypress Forums > USB Controllers > Reading GPIF transaction counter

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



Reading GPIF transaction counter
Moderator:
RSKV

Post Reply
Follow this topic



Reading GPIF transaction counter

ademenev posted on 01 Oct 2012 4:22 AM PST
Senior Member
12 Forum Posts

In FX2LP, transaction counter can be read while transaction is in progress. Is there a way to make an "atomic" read of the all 4 transaction count registers? Otherwise reading them is useless, because if an update occurs in between of read operation, the data read would be corrupted




Re: Reading GPIF transaction counter

RSKV posted on 07 Oct 2012 09:47 AM PST
Cypress Employee
655 Forum Posts

You should be able to read those 4 transaction registers at any point of time. I don't think data gets corrupted just because we are reading them. Did you encounter any situation where the data of these registers got corrupted?. Please let me know.

Thanks,

sai krishna.



Re: Reading GPIF transaction counter

ademenev posted on 31 Oct 2012 05:03 AM PST
Senior Member
12 Forum Posts

Suppose transaction count contains 0x00FFFF00.  I read lower byte - it is 0x00. Before I read other bytes, a transaction occors, and count now contains 0x00FFFEFF. And the final value I read is 0x00FFFE00 - totally wrong.



Re: Reading GPIF transaction counter

TheThinker posted on 14 Dec 2012 10:02 PM PST
Senior Member
17 Forum Posts

Hi,

Why do you want to read the transaction counter while there is a read/write operation is going on?
Are you somewhere in the firmware reading the values and doing any operations according to the values?
You can rather use FIFO Read/Write operation appropriately.

What are you exactly trying to implement with this logic?

Njoy...






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.