Am 18.11.2016 um 02:18 schrieb Bob Camp:
If you head of into ARM land (or even FPGA’s) there is a bit of a gotcha. If you
want to run a 10 MHz input and a PPS output, you need a counter with at least
24 bits. The peripherals on ARM chips are all over the place. Some have very
fancy timers, but o
Hi
If you head of into ARM land (or even FPGA’s) there is a bit of a gotcha. If
you
want to run a 10 MHz input and a PPS output, you need a counter with at least
24 bits. The peripherals on ARM chips are all over the place. Some have very
fancy timers, but only go to 16 bits. Some have 32 bit t
d anything in the datasheet.
> >
> >
> > -=Bryan=-
> >
> >
> > ________
> > From: time-nuts on behalf of Tom Van Baak
>
> > Sent: November 16, 2016 3:27 PM
> > To: Discussion of precise time and frequency measurement
&
Sorry, meant the ARM pin on the picdiv not the ARM MCU's
-=Bryan=-
From: time-nuts on behalf of Bob Camp
Sent: November 17, 2016 2:07 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] precision timing pulse
Hi
Ther
On Wed, Nov 16, 2016 at 8:52 PM, jimlux wrote:
> On 11/16/16 7:17 PM, Hal Murray wrote:
>
>>
>> t...@leapsecond.com said:
>>
>>> Arduino probably uses compiled code, external libraries, and interrupts
>>> so
>>> that also is a no-no for precise time.
>>>
>>
>> There are two parts to the Arduino e
For counting and timing the ARM has hardware counbter/timmer that is made
with logic gates so you don't need software or to disable interrupts.
Most modern uP has loads and loads of peripheral hardware built-in. With
the ARM there is a lot more of these peripheral devices than there are pins
on t
sday, November 17, 2016 1:26 PM
Subject: Re: [time-nuts] precision timing pulse
> Tom:
>
>
> As you were gracious to release the source code for these excellent little
> dividers, I would suspect someone who is somewhat fluent in assembly could
> just modify so it counts a s
rom: time-nuts on behalf of Tom Van Baak
>
> Sent: November 16, 2016 3:27 PM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] precision timing pulse
>
> Chris & Chris,
>
> Yes the "TVB dividers" are instruction loops
;t seem to find anything
in the datasheet.
-=Bryan=-
From: time-nuts on behalf of Tom Van Baak
Sent: November 16, 2016 3:27 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] precision timing pulse
Chris & Chris,
Yes the
On Wed, 16 Nov 2016 11:14:59 -0800, you wrote:
>albertson.ch...@gmail.com said:
>> I'm wondering why everyone seems to be assuming a PIC is the right processor
>
>If you want cycle-accurate timing, one approach is to count cycles. If you
>have an assembly level background, the PIC is as good as
On 11/17/16 4:45 AM, Bob Camp wrote:
Hi
On Nov 16, 2016, at 11:52 PM, jimlux wrote:
On 11/16/16 7:17 PM, Hal Murray wrote:
t...@leapsecond.com said:
Arduino probably uses compiled code, external libraries, and interrupts so
that also is a no-no for precise time.
There are two parts to t
On Wed, 16 Nov 2016 20:47:52 -0800
jimlux wrote:
> The BeagleBoard Black is a bigger, more capable example.. You can
> actually run a *nix on it, but has device drivers and such for lots of
> GPIO and timers.
And additionally has two PRU units, which are basically uC's with
cycle exact executi
Hi
> On Nov 16, 2016, at 11:52 PM, jimlux wrote:
>
> On 11/16/16 7:17 PM, Hal Murray wrote:
>>
>> t...@leapsecond.com said:
>>> Arduino probably uses compiled code, external libraries, and interrupts so
>>> that also is a no-no for precise time.
>>
>> There are two parts to the Arduino ecosys
On 11/16/16 7:17 PM, Hal Murray wrote:
t...@leapsecond.com said:
Arduino probably uses compiled code, external libraries, and interrupts so
that also is a no-no for precise time.
There are two parts to the Arduino ecosystem. One is low cost hardware. The
other is a software package that is
On 11/16/16 1:03 PM, Hal Murray wrote:
ch...@chriscaudle.org said:
but once you get to most of the ARM processors it is harder to make them
deterministic because of caches.
There are many ARM SOC chips that are half way between an Arduino and a
Raspberry Pi. They have GPIO and various serial
t...@leapsecond.com said:
> Arduino probably uses compiled code, external libraries, and interrupts so
> that also is a no-no for precise time.
There are two parts to the Arduino ecosystem. One is low cost hardware. The
other is a software package that is easy for non-wizards to use.
I'd be v
On Wed, Nov 16, 2016 at 1:03 PM, Hal Murray wrote:
> ch...@chriscaudle.org said:
> > but once you get to most of the ARM processors it is harder to make them
> > deterministic because of caches.
>
> There are many ARM SOC chips that are half way between an Arduino and a
> Raspberry Pi. They have
Chris & Chris,
Yes the "TVB dividers" are instruction loops where every cycle is counted by
hand, and then verified with a simulator, and then checked with a time interval
counter. All the code is out there at www.leapsecond.com/pic/
I use PIC's for historical and technical reasons. Modern CPU'
ch...@chriscaudle.org said:
> but once you get to most of the ARM processors it is harder to make them
> deterministic because of caches.
There are many ARM SOC chips that are half way between an Arduino and a
Raspberry Pi. They have GPIO and various serial ports and counter/timers.
They don't
thdsl.net
Sent: Wednesday, November 16, 2016 1:14 PM
Subject: Re: [time-nuts] precision timing pulse
albertson.ch...@gmail.com said:
> I'm wondering why everyone seems to be assuming a PIC is the right processor
If you want cycle-accurate timing, one approach is to count cycles. If you
On Wed, November 16, 2016 10:17 am, Chris Albertson wrote:
> I'm wondering why everyone seems to be assuming a PIC is the right
> processor.
You could use AVR (arduino), but once you get to most of the ARM
processors it is harder to make them deterministic because of caches. You
want a processor
albertson.ch...@gmail.com said:
> I'm wondering why everyone seems to be assuming a PIC is the right processor
If you want cycle-accurate timing, one approach is to count cycles. If you
have an assembly level background, the PIC is as good as any small chip.
Yes, it's a pain to get started if
I'm wondering why everyone seems to be assuming a PIC is the right
processor. Of course it could work for this but I'd select whatever is
the easiest to program and debug. Those tend to the they little single
board development systems that sell for under $10. They typically have USB
connection
The PIC can easily be programmed to be armed with a switch and stop at a
particular count, or you can use actual logic - debouncer, gating
flip-flop and programmable counter!
David N1HAC
On 11/15/16 1:57 PM, Chuck / Judy Burch wrote:
I'm building a laboratory scintillation counter that uses
___
> > From: time-nuts on behalf of Hal Murray <
> > hmur...@megapathdsl.net>
> > Sent: November 15, 2016 12:17 PM
> > To: Discussion of precise time and frequency measurement
> > Cc: hmur...@megapathdsl.net
> > Subject: Re: [time-nuts] precision timin
I'll add my 10 cents here. Because the accumulation time can be very long
555 class timers become a serious issue due to the large R&Cs involved.
I will guess some accuracy is desired.
As Chris says a start button to an arduino. The difference I might suggest
is a GPS 1sec PP into the arduino for c
.com/pic/picdiv.htm
>
>
> -=Bryan=-
>
>
>
> From: time-nuts on behalf of Hal Murray <
> hmur...@megapathdsl.net>
> Sent: November 15, 2016 12:17 PM
> To: Discussion of precise time and frequency measurement
> Cc: hmur...@megapathdsl.net
> Subject: Re: [time-nuts] p
If you are trying to avoid writing code, the 74hc might be worth taking
a look at.
On Tue, Nov 15, 2016 at 3:00 PM Chuck / Judy Burch
wrote:
>
> I'm building a laboratory scintillation counter that uses my HP 5335a
> counter as a read-out. The FREQ mode gives only approximate results
> (max
So you are already using a micro controller (a PIC) then
1) for the button input use an unused pin on the PIC. Connect the pin
to 5V via a 10K resister and then when you press the button it shorts
the pin to ground.The PIC then starts counting. A modern uP has
the 10K resister build into th
urray
Sent: November 15, 2016 12:17 PM
To: Discussion of precise time and frequency measurement
Cc: hmur...@megapathdsl.net
Subject: Re: [time-nuts] precision timing pulse
ciandjabu...@gmail.com said:
> How do I get a pulse to start with a push button and then stop for example
> 500 or 10,
You could build a simple one shot using something like a 555 timer IC
Or take a input pin from your PiC and use the RTC to drive a routine which
changes state of the pin for the duration of test
Content by Scott
Typos by Siri
> On Nov 15, 2016, at 1:57 PM, Chuck / Judy Burch
> wrote:
>
>
>
ciandjabu...@gmail.com said:
> How do I get a pulse to start with a push button and then stop for example
> 500 or 10,000 seconds later?
How about another PIC?
--
These are my opinions. I hate spam.
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time-nuts mailing list -- time-nuts@febo.
I'm building a laboratory scintillation counter that uses my HP 5335a
counter as a read-out. The FREQ mode gives only approximate results
(maximum gate time is about 5 seconds). The TOT mode counts pulses for
an arbitrary time that can be set using the "external arm input" on the
rear panel
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