RE: Source centered vs source sync
Hi,
I absolutely agree.
I would like to add that you do not need to use buffers/delay elements in
order to create the Source Centered clocking scheme, because in the source
you usually have 2x internal clock which allows you to create the
Delay-Shift in an accurate and process independent manner.
Boaz
> -----Original Message-----
> From: Devendra Tripathi [mailto:tripathi@xxxxxxxxxxx]
> Sent: Tuesday, September 26, 2000 7:51 PM
> To: stds-802-3-hssg@xxxxxxxx
> Subject: Source centered vs source sync
>
>
>
> Hi,
>
> One problem I found in implementing source synchronous design
> is that we need
> to adjust timing by inserting buffers. When worst case to
> best case ratio
> of delays
> are high, this becomes a tough problem to solve (especially
> when available
> time is
> a few ns). In centered clock case, this does not become a
> problem. There may be
> still buffers in clock/data paths but they track each other
> under various
> conditions.
> To take example of FC vs. GMII timings, I have found GMII
> timings (which are
> source sync.) much difficult to implement compared to FC
> (which is source
> centered).
>
> Regards,
> Tripathi.
>
>
> At 01:25 AM 9/26/00 -0700, you wrote:
> >stds-802-3-hssg@xxxxxxxx
>
> Best Regards,
>
> Devendra Tripathi
> Vitesse Semoconductor Corporation
> 3100 De La Cruz Boulevard
> Santa Clara, CA 95054
> Phone: (408) 986-4380 Ext 103
> Fax: (408) 986-6050
>