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Message
From: zx_mei@s...
Date: Sat, 16 Aug 2003 14:42:32 +0200
Subject: Re: [usb] low speed EOP -- clarification
hi, all
is there anyone who can share the low speed device core?ohterwise,
how difficult to write one?
----- Original Message -----
From: meizx@i...
To: usb@o...
Date: Mon, 21 Oct 2002 16:28:34 -0100
Subject: Re: [usb] low speed EOP -- clarification
>
>
> hi,
> You understanding of J state and speed bit time is actually
> correct.Furthermore,you can refer to Chapter7 table7.1 for detailed
> electriacal information and section 7.1.11 for detailed data
> signaling rate
> information.
>
> ----- Original Message -----
> From: "Srikanth K S" <skashyap@t... >
> To: usb@o...
> Date: Mon, 21 Oct 2002 12:50:18 +0530
> Subject: [usb] low speed EOP -- clarification
>
> > Hello All,
> > We had a doubt in USB 1.1 spec. section 11.5.1.10.
> >
> > USB 1.1 says:
> > 11.5.1.10 SendEOP
> > This state is entered from the Resuming state if the 20ms
> timer
> > expires. It is also entered from the Enabled state when an SOF
> (or
> > other FS token)
> > is received and a low-speed devices is attached to this port.
> In
> > this state, the hub will send a low-speed EOP (two low-speed
> bits
> > times
> > of SE0 followed by one low-speed bit times of J). At the end
> of the
> > EOP, the state ends. ..................................
> >
> > Our understanding:
> > When HC terminates the resume signal, it is done by sending
> > low-speed EOP (two low-speed bits times of SE0 followed by one
> > low-speed bit times of J). We infer that,
> > 1. the period of J of this EOP is = 1 low speed bit time (= 8
> bit
> > times of full speed) irrespective of the speed of the device
> and
> > 2. the signal strength is DIFFERENTIAL 0 for a low speed
> device and
> > DIFFERENTIAL 1 for a full speed device.
> >
> > Please give your feedback. Thanks in advance.
> > --------------------------------------------------------------
> > Srikanth Kashyap S.
> > --------------------------------------------------------------
> > But I don't have to know an answer.I don't feel frightened by
> > not knowing things, by being lost in the mysterious universe
> > without having any purpose, which is the way it really is, as
> > far as I can tell, possibly. It doesn't frighten me.
> > -- Richard P. Feynman
> > --------------------------------------------------------------
> >
> >
>
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