PORTS Forum

Ports and Interfaces => USB => Topic started by: USBVIDPID on August 22, 2012, 03:40:22 pm

Title: Max Full Speed Control EP Polling Rate?
Post by: USBVIDPID on August 22, 2012, 03:40:22 pm

What is the maximum polling rate allowed for a full speed control endpoint using EHCI Host?

Thx, jmw

Title: Re: Max Full Speed Control EP Polling Rate?
Post by: Barry Twycross on August 22, 2012, 05:27:13 pm

I just noticed you said control endpoint. You could possibly do it several times a ms. Table 5.2 of the spec tells you the maximum number of control requests you could possibly do depends on the transfer size, but is 32 for 1 byte transfers.

I'm not sure a real world EHCI controller could manage that though.