USB, select/poll for ucom
danny at cs.huji.ac.il
Sat Jun 28 02:37:13 PDT 2003
> have fun. the mindshare book is good. however, it took me a long
> time to get a usb 'aha' moment and understand its twisty maze was
> really a workable design obscured by standardese... I suspect it is a
> problem in the usb chipset driver for the com part. ttypoll just says
> 'you have data in the buffer' so for some reason the data isn't making
> into the tty buffer.
Im amazed at how some of you can write a driver based on the Spec. Docs!
here is a pearl i came across reading the USB spec for 1.1, page 43
'The maximum allowable interrupt data payload
size is 64 bytes or less for full-speed.'
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