lpcware

LPC1347 Composite Device Enumeration Problem

Discussion created by lpcware Employee on Jun 15, 2016
Content originally posted in LPCWare by ECamino on Fri Aug 21 05:33:04 MST 2015
Hi,

I have a composite device that:

1. Enumerates on Windows XP every time.
2. Enumerates on ubuntu 14 LTS about 9/10 times.
3. Enumerates on an Android STB with USB host about 1/5 times.

I used a USB protocol analyzer to see what's going on. I see a lot of IN txn (STALL) during enumeration. The device is eventually suspended by the USB Host. The analyzer shows Time Out errors.

My device is a composite with a USB keyboard and Vendor Defined HID interface.

The ROM USB stack, once initialized and USB connect called, is it "idiot proof?"  If not, then what could my code be doing so that my device won't enumerate sometimes on Linux and Android?

Thanks,

EC

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