Infinity Fabric = PCIe

By: Michael S (already5chosen.delete@this.yahoo.com), March 16, 2017 5:13 pm
Room: Moderated Discussions
Ricardo B (ricardo.b.delete@this.xxxxx.xx) on March 16, 2017 3:07 pm wrote:
> Michael S (already5chosen.delete@this.yahoo.com) on March 16, 2017 2:46 pm wrote:
> > Aaron Spink (aaronspink.delete@this.notearthlink.net) on March 16, 2017 11:11 am wrote:
> > > Michael S (already5chosen.delete@this.yahoo.com) on March 16, 2017 9:54 am wrote:
> > >
> > > > No, full QPI link consists from 4 quadrants, each with his own clock.
> > > >
> > > Pretty sure it is a single fwd clk per link which agrees with
> > > "Each link also has one and only one forwarded clock."
> > >
> > > While it is true that QPI has flexibility in quadrant allocation, the clk isn't replicated
> > > according to the public documentation. The individual lanes undergo an in depth training
> > > procedure and support periodic retraining. Can't remember if there is a disparity mechanism
> > > or not but it seams reasonable that at higher speeds it would be required.
> >
> > Yes, see above.
> > BTW, what is "disparity mechanism" ?
>
> Some mechanism to ensure it doesn't send too many consecutive 1 or 0.

Thanks. I never encountered it by name "disparity mechanism".
I probably invented a dozen of various schemes for such purpose in different shipping products, all without knowing that I construct disparity mechanisms. :-)

> Even for DC coupled links, it can help with the behaviour of transmitter/receiver.
> A popular one is, of course, 8B/10B (or 64B/66B) encoding.

8B/10B both assures high density of transitions and guarantees near-perfect DC balance.
In DC-coupled linked the later is unnecessary.

> But it's possible to come up with other schemes like "invert all bits if you've sent too many 0 or 1".
>
>
>
< Previous Post in ThreadNext Post in Thread >
TopicPosted ByDate
What is infinity fabric?slacker2017/03/12 06:41 PM
  What is infinity fabric?Jason Creighton2017/03/13 12:26 AM
    What is infinity fabric?Klimax2017/03/13 12:42 AM
      What is infinity fabric?Kevin G2017/03/13 04:39 AM
  What is infinity?Anon2017/03/13 04:44 AM
  What is infinity fabric?Groo2017/03/13 07:33 AM
    What is infinity fabric?Ireland2017/03/13 09:12 AM
      Another way to put same questionIreland2017/03/13 09:16 AM
      What is infinity fabric?Groo2017/03/13 12:12 PM
        What is infinity fabric?Ireland2017/03/13 02:07 PM
          What is infinity fabric?Ireland2017/03/13 02:32 PM
            What is infinity fabric?Seni2017/03/14 12:38 PM
          What is infinity fabric?Brendan2017/03/14 05:28 AM
            What is infinity fabric?Ireland2017/03/14 06:09 AM
            What is infinity fabric?Groo2017/03/14 07:35 AM
              What is infinity fabric?Ireland2017/03/14 08:35 AM
    Infinity Fabric = PCIeslacker2017/03/15 02:59 PM
      Infinity Fabric = PCIeMichael S2017/03/15 04:19 PM
        Infinity Fabric = PCIeIreland2017/03/15 04:49 PM
        Infinity Fabric = PCIeRicardo B2017/03/15 10:25 PM
        Infinity Fabric = PCIeslacker2017/03/15 10:45 PM
          Infinity Fabric = PCIeRicardo B2017/03/15 11:02 PM
            Infinity Fabric = PCIeAaron Spink2017/03/16 01:08 AM
              Infinity Fabric = PCIeRicardo B2017/03/16 05:30 AM
                Infinity Fabric = PCIeAaron Spink2017/03/16 10:58 AM
        Infinity Fabric = PCIeGabriele Svelto2017/03/16 03:48 AM
          Latency vs. bandwidthDavid Kanter2017/03/16 08:04 AM
      Infinity Fabric = PCIeGroo2017/03/15 05:35 PM
        Infinity Fabric = PCIeslacker2017/03/15 11:11 PM
          Infinity Fabric = PCIeAdrian2017/03/16 02:51 AM
            Infinity Fabric = PCIeMichael S2017/03/16 04:32 AM
              Infinity Fabric = PCIeAdrian2017/03/16 07:58 AM
                Infinity Fabric = PCIeRicardo B2017/03/16 09:16 AM
                  Infinity Fabric = PCIeMichael S2017/03/16 09:54 AM
                    Infinity Fabric = PCIeRicardo B2017/03/16 10:07 AM
                      Infinity Fabric = PCIeMichael S2017/03/16 02:33 PM
                        Infinity Fabric = PCIeGabriele Svelto2017/03/17 03:35 AM
                          Infinity Fabric = PCIeAaron Spink2017/03/17 10:25 AM
                            Thanks, your posts on this thread have been extremely informative (NT)Gabriele Svelto2017/03/17 01:08 PM
                            Infinity Fabric = PCIeRicardo B2017/03/17 06:08 PM
                              Infinity Fabric = PCIeAaron Spink2017/03/17 06:27 PM
                              Quickpath papers - circuits and implementationslacker2017/03/18 06:50 PM
                                Quickpath papers - circuits and implementationRicardo B2017/03/19 08:07 AM
                    Infinity Fabric = PCIeAaron Spink2017/03/16 11:11 AM
                      Infinity Fabric = PCIeMichael S2017/03/16 02:46 PM
                        Infinity Fabric = PCIeRicardo B2017/03/16 03:07 PM
                          Infinity Fabric = PCIeMichael S2017/03/16 05:13 PM
                            Infinity Fabric = PCIeAaron Spink2017/03/16 11:04 PM
                            Infinity Fabric = PCIeRicardo B2017/03/16 11:30 PM
                              Infinity Fabric = PCIeMichael S2017/03/17 07:24 AM
                                Infinity Fabric = PCIeRicardo B2017/03/17 06:07 PM
              Infinity Fabric = PCIeDavid Kanter2017/03/16 08:36 AM
                Infinity Fabric = PCIeMichael S2017/03/16 08:50 AM
                  Infinity Fabric = PCIeAaron Spink2017/03/16 11:24 AM
                    Infinity Fabric = PCIeMichael S2017/03/16 02:45 PM
                      Infinity Fabric = PCIeAaron Spink2017/03/16 11:21 PM
Reply to this Topic
Name:
Email:
Topic:
Body: No Text
How do you spell green?