|
Message
From: mdennis97@h...
Date: Tue, 17 Dec 2002 11:10:28 -0100
Subject: Re: [usb] dout of usb 1.1 function core
Thank you very much,rudi.
I find an interesting thing.In the function 2.0 core,you use SSRAM to
buffer the input and output data.In the 1.1 core,however,FIFO
instead.Why?
----- Original Message -----
From: Rudolf Usselmann <rudi@a... >
To: usb@o...
Date: 14 Dec 2002 10:48:04 +0700
Subject: Re: [usb] dout of usb 1.1 function core
>
>
> On Sat, 2002-12-14 at 13:02, mdennis97@h... wrote:
> > Thanks,rudi.You are right.I made a mistake for these wires.
> >
> > I have another question:why some signals of the PL module were
> not
> > handled?
> >
>
ie.,token_valid,int_to_set,int_seqerr_set,pid_cs_err,nse_err,crc5_err,rx_s
> > ize,rx_done,etc..
> >
> > Regards
> >
> > Dennis
>
>
> The USB 1.1 function was derived from the USB 2.0 function.
> The goal was to have a simple core for embedded applications.
> Those applications did not have a way to gracefully recover.
> If to many things go wrong the host will drop the function
> and you have to unplug and plug back in.
> Best case you just loose data and rely on higher level protocols
> to recognize it and deal with it. Other applications may not
> care so much (mice, cameras ...).
> Frames with those errors are just ignored/dropped - no recovery
> is implemented.
>
> rudi
> ------------------------------------------------
> www.asics.ws - Solutions for your ASIC needs -
> NEW ! 3 New Free IP Cores this months (so far :*)
> FREE IP Cores --> http://www.asics.ws/ <---
> ----- ALL SPAM forwarded to: UCE@F... -----
>
|
 |
Browse
