You are here

About Default USB Device | Cypress Semiconductor

About Default USB Device

Summary: 1 Reply, Latest post by PRJI on 07 May 2012 02:30 AM PDT
Verified Answers: 0
Last post
Log in to post new comments.
exact_bet's picture
1 post

I am reading EZ-USB_TRM.pdf, in the chapter 3, 3.6 The RENUM Bit, "Another Use for the Default USB Device", it says "By utilizing the Default USB Device (i.e., by
keeping RENUM=0), the firmware can, with very little code, perform meaningful USB transfers
that use these pre-configured endpoints.

My understanding is, by utilizing the default usb device, it will automatically handle any device request, and the firmware cannot handle the device request, therefore cannot perform meaningful USB transfers, right?

I think the cpu is held in reset states when RENUM = 0.


prji's picture
Cypress Employee
473 posts

 Firmware can also handle device requests. CPU is not in reset when RENUM=0. For more information please go through 2.3 USB Requests section of TRM.



Log in to post new comments.