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 <[email protected]> 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 <[email protected]> > 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, <[email protected]> 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:* [email protected] > > *Sent:* Thursday, February 22, 2018 4:29 PM > > *To:* [email protected] > > *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:* [email protected] > > *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: [email protected] > > To: [email protected] > > 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:* [email protected] > >> *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, [email protected] 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:* [email protected] > >>> *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, <[email protected]> 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. > >> > >> -- > > >
