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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