It's possible to use Bresenham with two integers 10,000,000 and
32,768 but I found no way to perform all the 24-bit calculations
on an 8-bit PIC quick enough. Removing the GCD often helps
but in this case the accumulator remains 3-bytes wide.
Huh? Dividing 10,000,000 by 4 (to match the PIC
Thanks for the info, Clint.
Seems like the only way to get my four Panasonic DVRs to synchronize
time is to analyze the I/O of the micro in the DVR, write interface
and HMI specs, and replace the micro with one that can talk to my
SNTP server. (Added two DVRs back when NASA was launching
Yes, DLL not DDL I made a mistake. Actually it is not in my schedule to
make such a divisor, just for speculation. The main thought here is that,
as you pointed out, it can be done avoiding PLL and DLL.
On Fri, Feb 3, 2012 at 1:49 AM, Hal Murray hmur...@megapathdsl.net wrote:
OK for the PSOC
I think I've seen comments about making 32 KHz from 10 MHz in a PIC or AVR.
tvb has this web page, but I don't see a 32 KHz option:
http://www.leapsecond.com/pic/picdiv.htm
Hal,
Yes, I have a PIC divider that takes 5 or 10 MHz input and
outputs a 32.768 kHz square wave with minimal jitter
://www.rbarrios.com
-Mensaje original-
From: Tom Van Baak
Sent: Thursday, February 02, 2012 10:34 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] ANFSCD - Synchronizing time in home video recorders
I think I've seen comments about making 32 KHz from 10 MHz
you,
Roberto EB4EQA
http://www.rbarrios.com
-Mensaje original-
From: Tom Van Baak
Sent: Thursday, February 02, 2012 10:34 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] ANFSCD - Synchronizing time in home video recorders
I think I've seen comments
it is done.
Thank you,
Roberto EB4EQA
http://www.rbarrios.com
-Mensaje original- From: Tom Van Baak
Sent: Thursday, February 02, 2012 10:34 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] ANFSCD - Synchronizing time in home video
recorders
I think
Message -
From: Azelio Boriani
To: Tom Van Baak ; Discussion of precise time and frequency measurement
Sent: Thursday, February 02, 2012 8:18 AM
Subject: Re: [time-nuts] ANFSCD - Synchronizing time in home video recorders
Amazing... there is always something to learn from TVB. Now
and frequency measurement
Sent: Thursday, February 02, 2012 8:18 AM
Subject: Re: [time-nuts] ANFSCD - Synchronizing time in home video
recorders
Amazing... there is always something to learn from TVB. Now I'll try to
derive a 2.048MHz G.703-13 clock from a 10MHz clock. I suspect
Subject: Re: [time-nuts] ANFSCD - Synchronizing time in home video recorders
Yes, shortly after having sent out the message I realized that I was, as
usual, too fast. I'm aware that a simple microprocessor can't be used but a
Spartan3 can be involved. Then another problem: the 2.048MHz is about 1
t...@leapsecond.com said:
I'm not sure how well a multi-level leap year algorithm relates Breseham's
algorithm. I tracked down his 1965 plotter article. There might be common
ground there.
It's the same math as a DDS.
If Breseham would land exactly on a grid point after N steps, a DDS will
OK for the PSOC example. At the moment I can try on a Spartan3 because I
already have a board with the OCXO. The Spartan3 has the so called DCM, a
digital clock generator that can multiply an input clock using its DDL
digital delay line.
On Thu, Feb 2, 2012 at 8:13 PM, Hal Murray
Years ago (in the 80's) I needed to lock a homebrew DDS to an accurate,
stable 10 MHz reference (a good TCXO in this case) that was set to
WWV/H. Considering that the DDS was clocked at 2^24 Hz (16.777216 MHz)
this was slightly awkward, but I did it using standard HC and 4000 logic.
The
No doubt, the correct way to generate accurate clocks from an accurate
10MHz is by PLLs. There are DDS too, then there is a strange method that
uses a sort of dual (triple? Quadruple? ...) modulus. The advantage is that
you don't need another oscillator (the PLL needs a VCO) or the (co)sine
lookup
... since the analogs went dark.
Are you near any Class-A or low-power stations? Those are still permitted to
broadcast NTSC signals. What's in their vertical interval would be a separate
question, though.
___
time-nuts mailing list --
OK for the PSOC example. At the moment I can try on a Spartan3 because I
already have a board with the OCXO. The Spartan3 has the so called DCM, a
digital clock generator that can multiply an input clock using its DDL
digital delay line.
The original context was keeping wall clock time. In
And now for something completely different:
Here I am with all of this precision time equipment, and I still
have to manually set time on the Digital Video Recorders (DVR)
because the TV channels that used to send a time code that the
DVR understood no longer do so. Seems like it died when
Failing that, can the crystal that determines time for the DVR be adjusted?
What sort of crystals do you find inside? My guess is there are two of them,
one at 32KHz used for timekeeping, and one at ?? MHz for the CPU.
I think I've seen comments about making 32 KHz from 10 MHz in a PIC or
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