Discussion:
IRIG B
(too old to reply)
Clive Green
2010-05-25 08:08:18 UTC
Permalink
Can anyone help with a modern IRIG B chipset manufacturer

Many thanks

Clive Green



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Rob Kimberley
2010-05-25 08:25:21 UTC
Permalink
Hello Clive.

I believe that Meinberg may have something. Take a look at the link below:-

http://www.pcidatabase.com/vendor_details.php?id=1623

Hope all going well.

Rob Kimberley

-----Original Message-----
From: time-nuts-bounces-***@public.gmane.org [mailto:time-nuts-bounces-***@public.gmane.org] On
Behalf Of Clive Green
Sent: 25 May 2010 9:08 AM
To: time-nuts-***@public.gmane.org
Subject: [time-nuts] IRIG B

Can anyone help with a modern IRIG B chipset manufacturer

Many thanks

Clive Green



Quartzlock

+ Gothic, Plymouth Road, Totnes, Devon. TQ9 5LH England

(: +44 (0) 1803 862 062 7: +44 (0) 1803 867 962

š: <mailto:nlaw-***@public.gmane.org> cgreen-***@public.gmane.org ü:
<http://www.quartzlock.com> www.quartzlock.com

Skype: clive.green.skype Messenger: cgreen-***@public.gmane.org

Registered office: Gothic, Plymouth Road, Totnes, Devon. TQ9 5LH England
Registered in England



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Hal Murray
2010-05-25 08:49:59 UTC
Permalink
> Can anyone help with a modern IRIG B chipset manufacturer

Send or receive?

The ntp package has software for both sides using PC audio cards.

--
These are my opinions, not necessarily my employer's. I hate spam.




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jimlux
2010-05-25 13:06:43 UTC
Permalink
Hal Murray wrote:
>> Can anyone help with a modern IRIG B chipset manufacturer
>
> Send or receive?
>
> The ntp package has software for both sides using PC audio cards.
>

I've been looking for an open-source IRIG B or E reader for FPGA use.

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Stanley Reynolds
2010-05-25 13:13:18 UTC
Permalink
Example of IRIG-B generator and decoder implemented in LabVIEW FPGA:

http://zone.ni.com/devzone/cda/epd/p/id/3396

Stanley

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jimlux
2010-05-25 15:09:22 UTC
Permalink
Stanley Reynolds wrote:
>
> Example of IRIG-B generator and decoder implemented in LabVIEW FPGA:
>
> http://zone.ni.com/devzone/cda/epd/p/id/3396
>
>

Thanks,
I was looking for something in VHDL or Verilog... I'm not sure how well
the Labview RIO, etc. stuff ports to non-Labview environments, but I'll
ask some Labview gurus about this one.

Thanks again
Jim

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Bob Camp
2010-05-25 11:38:34 UTC
Permalink
Hi

For full send / receive in hardware it looks like a "grab a FPGA and codec" sort of thing. Might be able to do it with a micro depending on the performance level.

Bob

On May 25, 2010, at 4:08 AM, Clive Green wrote:

> Can anyone help with a modern IRIG B chipset manufacturer
>
> Many thanks
>
> Clive Green
>
>
>
> Quartzlock
>
> + Gothic, Plymouth Road, Totnes, Devon. TQ9 5LH England
>
> (: +44 (0) 1803 862 062 7: +44 (0) 1803 867 962
>
> š: <mailto:nlaw-***@public.gmane.org> cgreen-***@public.gmane.org ü:
> <http://www.quartzlock.com> www.quartzlock.com
>
> Skype: clive.green.skype Messenger: cgreen-***@public.gmane.org
>
> Registered office: Gothic, Plymouth Road, Totnes, Devon. TQ9 5LH England
> Registered in England
>
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts-***@public.gmane.org
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jimlux
2010-05-25 13:03:29 UTC
Permalink
Clive Green wrote:
> Can anyone help with a modern IRIG B chipset manufacturer
>

I didn't know that there was such a thing, even in ancient times, much
less modern. All I've seen are designs made of discretes or programmed
in a microcontroller or FPGA.

Are you looking for a IRIG generator or receiver. DC or modulated on audio?

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Dean Weiten
2010-05-25 13:05:19 UTC
Permalink
Date: Tue, 25 May 2010 09:08:18 +0100
From: "Clive Green" <cgreen-***@public.gmane.org>
Subject: [time-nuts] IRIG B
To: <time-nuts-***@public.gmane.org>
Message-ID: <000d01cafbe1$6f6788b0$4e369a10$@com>
Content-Type: text/plain; charset="iso-8859-2"

Can anyone help with a modern IRIG B chipset manufacturer

Many thanks

Clive Green

----------------------

Hi Clive and the group.

I can't give you a lead on an ready-made chipset, but I've implemented an IRIG-B decoder in a 68HC11 and in an 68HCS12. I found the difficult part to be the analog section, as it can introduce significant uncertainties in the timing stream, especially in a modulated signal. We got ours down to around 10 uSec which we considered quite good. Of course the 5 volt logic levels of the unmodulated signal makes it easier to get better accuracy.

The IRIG-B decoder work I did was implemented on power systems relays & disturbance recorders several years ago, then I left the company and in the meantime, they changed over to an FPGA implementation and skipped the processor altogether. Now I'm back with that same company (although ownership has changed), but I haven't yet had a chat with the new FPGA designer to find out how he did it :-)

I've also tweaked and "upgraded" (well in my opinion) the TG program of the NTP package, which generates WWV(H) and IRIG-B audio signals in *NIX operating systems. It was targeted for the Sun Sparc and I moved it to OSS audio which was what I was using on X86 GNU/LINUX at the time. I think I submitted it for inclusion in the NTP package but I don't think it ever got in there; I used to claim that it was rejected, but then again it's also possible that I didn't submit it correctly. I can give this to you if you would like.

If you would advise on your application and parametric requirements, perhaps I (or someone else on the mailing list) could make further suggestion or help directly.

--

Dean Weiten


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Bob Camp
2010-05-25 16:05:08 UTC
Permalink
Hi

Audio codecs (especially monophonic ones) are pretty cheap these days.
Depending on volume they can get to the sub $1 range. Even in small quantity
they are below $4. That makes them a pretty tempting "front end" for a send
/ receive box.

Bob

-----Original Message-----
From: time-nuts-bounces-***@public.gmane.org [mailto:time-nuts-bounces-***@public.gmane.org] On
Behalf Of Dean Weiten
Sent: Tuesday, May 25, 2010 9:05 AM
To: cgreen-***@public.gmane.org
Cc: time-nuts-***@public.gmane.org
Subject: Re: [time-nuts] IRIG B

Date: Tue, 25 May 2010 09:08:18 +0100
From: "Clive Green" <cgreen-***@public.gmane.org>
Subject: [time-nuts] IRIG B
To: <time-nuts-***@public.gmane.org>
Message-ID: <000d01cafbe1$6f6788b0$4e369a10$@com>
Content-Type: text/plain; charset="iso-8859-2"

Can anyone help with a modern IRIG B chipset manufacturer

Many thanks

Clive Green

----------------------

Hi Clive and the group.

I can't give you a lead on an ready-made chipset, but I've implemented an
IRIG-B decoder in a 68HC11 and in an 68HCS12. I found the difficult part to
be the analog section, as it can introduce significant uncertainties in the
timing stream, especially in a modulated signal. We got ours down to around
10 uSec which we considered quite good. Of course the 5 volt logic levels
of the unmodulated signal makes it easier to get better accuracy.

The IRIG-B decoder work I did was implemented on power systems relays &
disturbance recorders several years ago, then I left the company and in the
meantime, they changed over to an FPGA implementation and skipped the
processor altogether. Now I'm back with that same company (although
ownership has changed), but I haven't yet had a chat with the new FPGA
designer to find out how he did it :-)

I've also tweaked and "upgraded" (well in my opinion) the TG program of the
NTP package, which generates WWV(H) and IRIG-B audio signals in *NIX
operating systems. It was targeted for the Sun Sparc and I moved it to OSS
audio which was what I was using on X86 GNU/LINUX at the time. I think I
submitted it for inclusion in the NTP package but I don't think it ever got
in there; I used to claim that it was rejected, but then again it's also
possible that I didn't submit it correctly. I can give this to you if you
would like.

If you would advise on your application and parametric requirements, perhaps
I (or someone else on the mailing list) could make further suggestion or
help directly.

--

Dean Weiten


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Don Latham
2010-05-25 17:20:09 UTC
Permalink
16 bit audio interfaces with USB adapters (cheap sound cards) are
available made in the old country for less than ten inflated rasbuckniks
on epray...
Don

Bob Camp
> Hi
>
> Audio codecs (especially monophonic ones) are pretty cheap these days.
> Depending on volume they can get to the sub $1 range. Even in small
> quantity
> they are below $4. That makes them a pretty tempting "front end" for a
> send
> / receive box.
>
> Bob
>
> -----Original Message-----
> From: time-nuts-bounces-***@public.gmane.org [mailto:time-nuts-bounces-***@public.gmane.org] On
> Behalf Of Dean Weiten
> Sent: Tuesday, May 25, 2010 9:05 AM
> To: cgreen-***@public.gmane.org
> Cc: time-nuts-***@public.gmane.org
> Subject: Re: [time-nuts] IRIG B
>
> Date: Tue, 25 May 2010 09:08:18 +0100
> From: "Clive Green" <cgreen-***@public.gmane.org>
> Subject: [time-nuts] IRIG B
> To: <time-nuts-***@public.gmane.org>
> Message-ID: <000d01cafbe1$6f6788b0$4e369a10$@com>
> Content-Type: text/plain; charset="iso-8859-2"
>
> Can anyone help with a modern IRIG B chipset manufacturer
>
> Many thanks
>
> Clive Green
>
> ----------------------
>
> Hi Clive and the group.
>
> I can't give you a lead on an ready-made chipset, but I've implemented an
> IRIG-B decoder in a 68HC11 and in an 68HCS12. I found the difficult part
> to
> be the analog section, as it can introduce significant uncertainties in
> the
> timing stream, especially in a modulated signal. We got ours down to
> around
> 10 uSec which we considered quite good. Of course the 5 volt logic levels
> of the unmodulated signal makes it easier to get better accuracy.
>
> The IRIG-B decoder work I did was implemented on power systems relays &
> disturbance recorders several years ago, then I left the company and in
> the
> meantime, they changed over to an FPGA implementation and skipped the
> processor altogether. Now I'm back with that same company (although
> ownership has changed), but I haven't yet had a chat with the new FPGA
> designer to find out how he did it :-)
>
> I've also tweaked and "upgraded" (well in my opinion) the TG program of
> the
> NTP package, which generates WWV(H) and IRIG-B audio signals in *NIX
> operating systems. It was targeted for the Sun Sparc and I moved it to
> OSS
> audio which was what I was using on X86 GNU/LINUX at the time. I think I
> submitted it for inclusion in the NTP package but I don't think it ever
> got
> in there; I used to claim that it was rejected, but then again it's also
> possible that I didn't submit it correctly. I can give this to you if you
> would like.
>
> If you would advise on your application and parametric requirements,
> perhaps
> I (or someone else on the mailing list) could make further suggestion or
> help directly.
>
> --
>
> Dean Weiten
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts-***@public.gmane.org
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
>
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts-***@public.gmane.org
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>


--
"Neither the voice of authority nor the weight of reason and argument are
as significant as experiment, for thence comes quiet to the mind."
R. Bacon


Dr. Don Latham AJ7LL
Six Mile Systems LLP
17850 Six Mile Road
POB 134
Huson, MT, 59846
VOX 406-626-4304
www.lightningforensics.com
www.sixmilesystems.com


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Bob Camp
2010-05-25 21:12:47 UTC
Permalink
Hi

I *think* Clive is looking for a chip set to put on a pc board in a product.

Bob

-----Original Message-----
From: time-nuts-bounces-***@public.gmane.org [mailto:time-nuts-bounces-***@public.gmane.org] On
Behalf Of Don Latham
Sent: Tuesday, May 25, 2010 1:20 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] IRIG B

16 bit audio interfaces with USB adapters (cheap sound cards) are
available made in the old country for less than ten inflated rasbuckniks
on epray...
Don

Bob Camp
> Hi
>
> Audio codecs (especially monophonic ones) are pretty cheap these days.
> Depending on volume they can get to the sub $1 range. Even in small
> quantity
> they are below $4. That makes them a pretty tempting "front end" for a
> send
> / receive box.
>
> Bob
>
> -----Original Message-----
> From: time-nuts-bounces-***@public.gmane.org [mailto:time-nuts-bounces-***@public.gmane.org] On
> Behalf Of Dean Weiten
> Sent: Tuesday, May 25, 2010 9:05 AM
> To: cgreen-***@public.gmane.org
> Cc: time-nuts-***@public.gmane.org
> Subject: Re: [time-nuts] IRIG B
>
> Date: Tue, 25 May 2010 09:08:18 +0100
> From: "Clive Green" <cgreen-***@public.gmane.org>
> Subject: [time-nuts] IRIG B
> To: <time-nuts-***@public.gmane.org>
> Message-ID: <000d01cafbe1$6f6788b0$4e369a10$@com>
> Content-Type: text/plain; charset="iso-8859-2"
>
> Can anyone help with a modern IRIG B chipset manufacturer
>
> Many thanks
>
> Clive Green
>
> ----------------------
>
> Hi Clive and the group.
>
> I can't give you a lead on an ready-made chipset, but I've implemented an
> IRIG-B decoder in a 68HC11 and in an 68HCS12. I found the difficult part
> to
> be the analog section, as it can introduce significant uncertainties in
> the
> timing stream, especially in a modulated signal. We got ours down to
> around
> 10 uSec which we considered quite good. Of course the 5 volt logic levels
> of the unmodulated signal makes it easier to get better accuracy.
>
> The IRIG-B decoder work I did was implemented on power systems relays &
> disturbance recorders several years ago, then I left the company and in
> the
> meantime, they changed over to an FPGA implementation and skipped the
> processor altogether. Now I'm back with that same company (although
> ownership has changed), but I haven't yet had a chat with the new FPGA
> designer to find out how he did it :-)
>
> I've also tweaked and "upgraded" (well in my opinion) the TG program of
> the
> NTP package, which generates WWV(H) and IRIG-B audio signals in *NIX
> operating systems. It was targeted for the Sun Sparc and I moved it to
> OSS
> audio which was what I was using on X86 GNU/LINUX at the time. I think I
> submitted it for inclusion in the NTP package but I don't think it ever
> got
> in there; I used to claim that it was rejected, but then again it's also
> possible that I didn't submit it correctly. I can give this to you if you
> would like.
>
> If you would advise on your application and parametric requirements,
> perhaps
> I (or someone else on the mailing list) could make further suggestion or
> help directly.
>
> --
>
> Dean Weiten
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts-***@public.gmane.org
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
>
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts-***@public.gmane.org
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>


--
"Neither the voice of authority nor the weight of reason and argument are
as significant as experiment, for thence comes quiet to the mind."
R. Bacon


Dr. Don Latham AJ7LL
Six Mile Systems LLP
17850 Six Mile Road
POB 134
Huson, MT, 59846
VOX 406-626-4304
www.lightningforensics.com
www.sixmilesystems.com


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Magnus Danielson
2010-05-25 22:30:59 UTC
Permalink
On 05/25/2010 11:12 PM, Bob Camp wrote:
> Hi
>
> I *think* Clive is looking for a chip set to put on a pc board in a product.

Me too, but I think the reality is that I don't think there is such a
thing except maybe in some early ASICs. Today FPGAs rule that world. The
benefit is naturally that functional updates can come cheaply if
provision is made for remove firmware updates.:)

The closest I can come up with is maybe WWV receiver chips. But that is
IRIG-H and not IRIG-B.

The only reasons for heading down the audio ADC/DAC route over 8-bit is
dynamic range and cost. It makes sense for IRIG-B102 signals.

Cheers,
Magnus

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Bob Camp
2010-05-25 23:09:35 UTC
Permalink
Hi

Like all the rest of us I'm making assumptions. I *assume* that we're talking about an implementation that will handle IRIG over audio over a fairly wide dynamic range.

Bob


On May 25, 2010, at 6:30 PM, Magnus Danielson wrote:

> On 05/25/2010 11:12 PM, Bob Camp wrote:
>> Hi
>>
>> I *think* Clive is looking for a chip set to put on a pc board in a product.
>
> Me too, but I think the reality is that I don't think there is such a thing except maybe in some early ASICs. Today FPGAs rule that world. The benefit is naturally that functional updates can come cheaply if provision is made for remove firmware updates.:)
>
> The closest I can come up with is maybe WWV receiver chips. But that is IRIG-H and not IRIG-B.
>
> The only reasons for heading down the audio ADC/DAC route over 8-bit is dynamic range and cost. It makes sense for IRIG-B102 signals.
>
> Cheers,
> Magnus
>
> _______________________________________________
> time-nuts mailing list -- time-nuts-***@public.gmane.org
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
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>


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Magnus Danielson
2010-05-25 23:23:37 UTC
Permalink
On 05/26/2010 01:09 AM, Bob Camp wrote:
> Hi
>
> Like all the rest of us I'm making assumptions. I *assume* that we're talking about an implementation that will handle IRIG over audio over a fairly wide dynamic range.

Well, like most cases, I'd assume it is over "sufficient" dynamic range.
The signal itself doesn't require very high dynamics, 8 bit should work
well, 12 bits should allow for less care in level settings, 24 bits is
excessive but cheap and only real care is high amplitude/clipping.

Cheers,
Magnus

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Bob Camp
2010-05-25 23:32:11 UTC
Permalink
Hi

Most of the cheap codecs are 24 bits "as advertised" and maybe 16 bits "as measured".

That puts them in a nice comfort zone a bit past the 10 or 12 bits you get from a micro.

Bob


On May 25, 2010, at 7:23 PM, Magnus Danielson wrote:

> On 05/26/2010 01:09 AM, Bob Camp wrote:
>> Hi
>>
>> Like all the rest of us I'm making assumptions. I *assume* that we're talking about an implementation that will handle IRIG over audio over a fairly wide dynamic range.
>
> Well, like most cases, I'd assume it is over "sufficient" dynamic range. The signal itself doesn't require very high dynamics, 8 bit should work well, 12 bits should allow for less care in level settings, 24 bits is excessive but cheap and only real care is high amplitude/clipping.
>
> Cheers,
> Magnus
>
> _______________________________________________
> time-nuts mailing list -- time-nuts-***@public.gmane.org
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
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>


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Hal Murray
2010-05-25 18:49:54 UTC
Permalink
> The IRIG-B decoder work I did was implemented on power systems relays &
> disturbance recorders several years ago, then I left the company and in the
> meantime, they changed over to an FPGA implementation and skipped the
> processor altogether. Now I'm back with that same company (although
> ownership has changed), but I haven't yet had a chat with the new FPGA
> designer to find out how he did it :-)

Interesting. I'd like to know why they switched to FPGA.

I thought the consensus in the FPGA world was that if you could do it in
software that was probably the better way to go. The main idea is that it's
easier to hire programmers than FPGA designers.

I'd expect silicon costs to be roughly equal. In a FPGA you are "wasting" a
lot of silicon for routing. In a CPU, you are wasting it on instruction
decoding. Both are high volume parts riding the crest of Moore's Law. Of
course, algorithm details may push you one way or the other.


> I've also tweaked and "upgraded" (well in my opinion) the TG program of the
> NTP package, which generates WWV(H) and IRIG-B audio signals in *NIX
> operating systems. It was targeted for the Sun Sparc and I moved it to OSS
> audio which was what I was using on X86 GNU/LINUX at the time. I think I
> submitted it for inclusion in the NTP package but I don't think it ever got
> in there; I used to claim that it was rejected, but then again it's also
> possible that I didn't submit it correctly. I can give this to you if you
> would like.

It's in there. Thanks. I called it tg2 because I couldn't test it in the
Sun world and I wanted to make sure I didn't break anything.

The recipe for getting fixes into the NTP package is pretty simple: find an
insider who likes your changes. Mechanically, their bugzilla is at
https://support.ntp.org/bugs/index.cgi
That tracks enhancements/wishes as well as bugs. You can upload diffs and
such.

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Bob Camp
2010-05-25 21:14:59 UTC
Permalink
Hi

A lot of the codec's talk I2S. That's not a real popular item in the
embedded processor world. If you are already running a FPGA, the IRIG might
fit in the "empty" part of the chip. You often have to bump up 1.5 or 2:1
when you run out of this or that.

Bob

-----Original Message-----
From: time-nuts-bounces-***@public.gmane.org [mailto:time-nuts-bounces-***@public.gmane.org] On
Behalf Of Hal Murray
Sent: Tuesday, May 25, 2010 2:50 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] IRIG B


> The IRIG-B decoder work I did was implemented on power systems relays &
> disturbance recorders several years ago, then I left the company and in
the
> meantime, they changed over to an FPGA implementation and skipped the
> processor altogether. Now I'm back with that same company (although
> ownership has changed), but I haven't yet had a chat with the new FPGA
> designer to find out how he did it :-)

Interesting. I'd like to know why they switched to FPGA.

I thought the consensus in the FPGA world was that if you could do it in
software that was probably the better way to go. The main idea is that it's

easier to hire programmers than FPGA designers.

I'd expect silicon costs to be roughly equal. In a FPGA you are "wasting" a

lot of silicon for routing. In a CPU, you are wasting it on instruction
decoding. Both are high volume parts riding the crest of Moore's Law. Of
course, algorithm details may push you one way or the other.


> I've also tweaked and "upgraded" (well in my opinion) the TG program of
the
> NTP package, which generates WWV(H) and IRIG-B audio signals in *NIX
> operating systems. It was targeted for the Sun Sparc and I moved it to
OSS
> audio which was what I was using on X86 GNU/LINUX at the time. I think I
> submitted it for inclusion in the NTP package but I don't think it ever
got
> in there; I used to claim that it was rejected, but then again it's also
> possible that I didn't submit it correctly. I can give this to you if you
> would like.

It's in there. Thanks. I called it tg2 because I couldn't test it in the
Sun world and I wanted to make sure I didn't break anything.

The recipe for getting fixes into the NTP package is pretty simple: find an
insider who likes your changes. Mechanically, their bugzilla is at
https://support.ntp.org/bugs/index.cgi
That tracks enhancements/wishes as well as bugs. You can upload diffs and
such.

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Hal Murray
2010-05-25 19:00:07 UTC
Permalink
> For full send / receive in hardware it looks like a "grab a FPGA and codec"
> sort of thing. Might be able to do it with a micro depending on the
> performance level.

It doesn't take a lot of CPU.

I have a 433 MHz AMD Geode (i386 clone) running ntpd's IRIG decoder. Top
says the CPU usage bounces around a lot. Typical large samples are 2.3%.
Round that up and we are talking 20 MHz. It would be fun to get it running
an an ARM and see how slow it could go. (Or pick your favorite embedded CPU.)

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Hal Murray
2010-05-25 19:21:19 UTC
Permalink
> Audio codecs (especially monophonic ones) are pretty cheap these days.
> Depending on volume they can get to the sub $1 range. Even in small quantity
> they are below $4. That makes them a pretty tempting "front end" for a send /
> receive box.

I got an interesting education in silicon economics 5-8 years ago.

We were looking for a low cost audio A/D. A guy from TI suggested using a
codec and ignoring the other half. (The idea of throwing away half of a chip
had never occurred to me.)


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