About Default USB Device

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Anonymous
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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.

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Anonymous
Not applicable

 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.

   

Thanks

   

Prajith

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