Yes, and one would think that Metaswitch would have a 10 MHz input.  

From: Lewis Bergman 
Sent: Friday, February 23, 2018 6:44 AM
To: af@afmug.com 
Subject: Re: [AFMUG] OT Raspberry PI

Every Rubidium GPS timing piece of gear I have ever seen outputs 10MHz. Every 
device that I have ever seen that takes a timing signal requires 10MHz. I 
probably have lead a sheltered life but I haven't seen anything else.

On Fri, Feb 23, 2018 at 12:06 AM Robert <i...@avantwireless.com> wrote:

  https://en.wikipedia.org/wiki/ECos

  On 2/22/18 5:52 PM, Chuck McCown wrote:
  > That looks great.  Did not find a cost anywhere.
  > *From:* Bill Prince
  > *Sent:* Thursday, February 22, 2018 6:47 PM
  > *To:* Motorola III
  > *Subject:* Re: [AFMUG] OT Raspberry PI
  > Try this: http://www.ecoscentric.com/news/press-170314.shtml
  >
  > --bp
  > --
  > bp
  > part15sbs{at}gmail{dot}com
  > On Thu, Feb 22, 2018 at 3:56 PM, Bill Prince <part15...@gmail.com> wrote:
  >
  >     Pretty sure you need  RTOS to accomplish this.That will get pretty
  >     close to bare metal.
  >
  >     -bp
  >     --
  >     bp
  >     part15sbs{at}gmail{dot}com
  >     On Thu, Feb 22, 2018 at 3:36 PM, <ch...@wbmfg.com> wrote:
  >
  >         Had the command syntax wrong.
  >         But got nice to work.  Have to sudo if you use negative nice
  >         numbers.
  >         It made zero difference in my jitter.  I went from 19 to –20 on
  >         nice and no change.
  >         *From:* ch...@wbmfg.com
  >         *Sent:* Thursday, February 22, 2018 4:29 PM
  >         *To:* af@afmug.com
  >         *Subject:* Re: [AFMUG] OT Raspberry PI
  >         The problem is there is a crap ton of stuff out there that needs
  >         network sync.  And it all has a T1 as an input.
  >         But most T1 trunking circuits are getting replaced with SIP.
  >         So, I am building a cheap and dirty T1 signal generator that is
  >         GPS and rhubidium referenced.  The hard part is easy.  The easy
  >         part should be easy but all the T1 framing chips that used to
  >         exist no longer exist.
  >         The ones that are out there have massive CPU interfaces and tons
  >         of registers that need to get set to get them fired up and
  >         running....
  >         Where is Exar when you need them....
  >         *From:* Adam Moffett
  >         *Sent:* Thursday, February 22, 2018 4:21 PM
  >         *To:* af@afmug.com
  >         *Subject:* Re: [AFMUG] OT Raspberry PI
  >         Tell whoever's got the T1 that 1967 is way behind us and get a
  >         new interface.
  >         Problem eliminated LOL
  >         ------ Original Message ------
  >         From: ch...@wbmfg.com
  >         To: af@afmug.com
  >         Sent: 2/22/2018 6:16:45 PM
  >         Subject: Re: [AFMUG] OT Raspberry PI
  >>         I have to generate an alternate mark inversion signal on 1.544
  >>         MHz with every 193rd bit following a t1 framing sequence.
  >>         Sure wish a 555 could do that.
  >>         *From:* Dave
  >>         *Sent:* Thursday, February 22, 2018 4:10 PM
  >>         *To:* af@afmug.com
  >>         *Subject:* Re: [AFMUG] OT Raspberry PI
  >>         Find a 555 timer ... I used many in the olden day when
  >>         radioshacks were king LOL!
  >>
  >>
  >>         On 02/22/2018 05:05 PM, ch...@wbmfg.com wrote:
  >>>         I am thinking of using some shift registers instead of using
  >>>         the PI output directly as the timing signal.
  >>>         Use the PI to load them.
  >>>         I love me some hardware design anyhow....
  >>>         *From:* Colin Stanners
  >>>         *Sent:* Thursday, February 22, 2018 3:59 PM
  >>>         *To:* af@afmug.com
  >>>         *Subject:* Re: [AFMUG] OT Raspberry PI
  >>>         Other than setting the process priority, you may need a
  >>>         custom kernel. See
  >>>         
https://medium.com/@metebalci/latency-of-raspberry-pi-3-on-standard-and-real-time-linux-4-9-kernel-2d9c20704495
  >>>         
<https://medium.com/@metebalci/latency-of-raspberry-pi-3-on-standard-and-real-time-linux-4-9-kernel-2d9c20704495>
  >>>
  >>>         On Feb 22, 2018 4:48 PM, <ch...@wbmfg.com> wrote:
  >>>
  >>>             Anyone know how to get my program to run on bare metal?
  >>>             Or at the very least tell Linux that my program is the
  >>>             most important thing in the world and service it above
  >>>             all other things.
  >>>             I am trying to create a timing signal with the Pi.  It is
  >>>             doing it but the jitter is pretty bad.
  >>>             I have researched trying to use an interrupt but there is
  >>>             a pretty low limit on how many times per second you can
  >>>             fire a hardware interrupt.
  >>>             Too low for my application.
  >>
  >>         --
  >

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