Wanted: A Very Accurate Timer
Sear...@mail.con2.com
can buy?
It must to be accurate to within 1/60th of a second over the course of
6 hours.
Is something like this commercially available, or will I have to build
it, or have someone build it?
Any advice would be appreciated.
Thanks a lot.
Darren Harris
Staten Island, New York.
Ian Stirling
> Can I get recomendations for the most accurate electronic timer that I
> can buy?
>
> It must to be accurate to within 1/60th of a second over the course of
> 6 hours.
>
> Is something like this commercially available, or will I have to build
> it, or have someone build it?
GPS recievers.
I've seen some with an alarm function.
However, 1/60th of a second in 6 hours isn't impossible to do otherwise.
Jim Thompson
wrote:
An ordinary digital clock powered from the AC line is more accurate
than that.
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Richard Henry
"Jim Thompson" <thegr...@example.com> wrote in message
news:kggob1t5oeo0lqt14...@4ax.com...
> On 24 Jun 2005 17:19:09 GMT, Ian Stirling <ro...@mauve.demon.co.uk>
> wrote:
>
> >In sci.electronics.design Sear...@mail.con2.com wrote:
> >> Can I get recomendations for the most accurate electronic timer that I
> >> can buy?
> >>
> >> It must to be accurate to within 1/60th of a second over the course of
> >> 6 hours.
> >>
> >> Is something like this commercially available, or will I have to build
> >> it, or have someone build it?
> >
> >GPS recievers.
> >I've seen some with an alarm function.
> >However, 1/60th of a second in 6 hours isn't impossible to do otherwise.
>
> An ordinary digital clock powered from the AC line is more accurate
> than that.
On the surface, shouldn't that be "as accurate as that"? In North America
and other 60-Hz realms, at least.
I have heard horror stories about short-term inaccuracies in the power
system 60 Hz timing, that it is only guaranteed to be accurate within 1
cycle per day, for instance.
And I found this tidbit googling around for accurate clocks: "GPS time was
zero at 0h 6-Jan-1980 and since it is not perturbed by leap seconds GPS is
now ahead of UTC by 13 seconds."
Jim Thompson
wrote:
>
>"Jim Thompson" <thegr...@example.com> wrote in message
>news:kggob1t5oeo0lqt14...@4ax.com...
>> On 24 Jun 2005 17:19:09 GMT, Ian Stirling <ro...@mauve.demon.co.uk>
>> wrote:
>>
>> >In sci.electronics.design Sear...@mail.con2.com wrote:
>> >> Can I get recomendations for the most accurate electronic timer that I
>> >> can buy?
>> >>
>> >> It must to be accurate to within 1/60th of a second over the course of
>> >> 6 hours.
>> >>
>> >> Is something like this commercially available, or will I have to build
>> >> it, or have someone build it?
>> >
>> >GPS recievers.
>> >I've seen some with an alarm function.
>> >However, 1/60th of a second in 6 hours isn't impossible to do otherwise.
>>
>> An ordinary digital clock powered from the AC line is more accurate
>> than that.
>
>On the surface, shouldn't that be "as accurate as that"? In North America
>and other 60-Hz realms, at least.
As I understand it, for grid-power-hopping to work, the accuracy is
_much_ better than that.
>
>I have heard horror stories about short-term inaccuracies in the power
>system 60 Hz timing, that it is only guaranteed to be accurate within 1
>cycle per day, for instance.
I think that's nonsense.
>
>And I found this tidbit googling around for accurate clocks: "GPS time was
>zero at 0h 6-Jan-1980 and since it is not perturbed by leap seconds GPS is
>now ahead of UTC by 13 seconds."
>
Tim Hubberstey
>>In sci.electronics.design Sear...@mail.con2.com wrote:
>>
>>>Can I get recomendations for the most accurate electronic timer that I
>>>can buy?
>>>
>>>It must to be accurate to within 1/60th of a second over the course of
>>>6 hours.
>>>
> An ordinary digital clock powered from the AC line is more accurate
> than that.
Only when averaged over at least a day. The OP needs accuracy of about
0.5 ppm, while the short-term accuracy of the AC line is no better than
600 ppm (0.1 Hz), IIRC.
A quick Google search shows 0.5 ppm as a spec available for many TCXOs,
so this can be built (relatively) cheaply using a TCXO and a
microcontroller.
--
Tim Hubberstey, P.Eng. . . . . . Hardware/Software Consulting Engineer
Marmot Engineering . . . . . . . VHDL, ASICs, FPGAs, embedded systems
Vancouver, BC, Canada . . . . . . . . . . . http://www.marmot-eng.com
EL
>
> "Jim Thompson" <thegr...@example.com> wrote in message
> news:kggob1t5oeo0lqt14...@4ax.com...
>> On 24 Jun 2005 17:19:09 GMT, Ian Stirling <ro...@mauve.demon.co.uk>
>> wrote:
>>
>> >In sci.electronics.design Sear...@mail.con2.com wrote:
>> >> Can I get recomendations for the most accurate electronic timer that I
>> >> can buy?
>> >>
>> >> It must to be accurate to within 1/60th of a second over the course of
>> >> 6 hours.
>> >>
>> >> Is something like this commercially available, or will I have to build
>> >> it, or have someone build it?
>> >
>> >GPS recievers.
>> >I've seen some with an alarm function.
>> >However, 1/60th of a second in 6 hours isn't impossible to do otherwise.
>>
>> An ordinary digital clock powered from the AC line is more accurate
>> than that.
>
> On the surface, shouldn't that be "as accurate as that"? In North America
> and other 60-Hz realms, at least.
>
> I have heard horror stories about short-term inaccuracies in the power
> system 60 Hz timing, that it is only guaranteed to be accurate within 1
> cycle per day, for instance.
*** GASP!!!!!! ***
An error of one part in 5,184,000??!?!?!?!?!
How could anyone possibly tolerate that???!?!?!?!?!
;^)
Richard Henry
"EL" <nos...@here.com> wrote in message
news:42bc5a36$0$5749$9a6e...@news.newshosting.com...
I recall working with a marketing guy a few years back who had a customer
interested in a ruggedized PC that had timing accurate to 1 second/month,
even when turned off. He thought the PC's real-time clock chip would be ok,
because it has its own battery.
DaveM
news:1119630929.6...@g47g2000cwa.googlegroups.com...
Dan,
Sadly enough, there have been a number of replies to your question, but none
have attempted to answer it directly.
But, you didn't state the intended use or desired method of operation of the
timer. Assuming that you are looking for a handheld timer suitable for
tasks such as cooking or sunbathing, almost any of the common timers
available at outlets such as Radio Shack, Target, Walmart, etc. should fill
your bill. They are all crystal controlled, and although their accuracy
isn't usually stated in the specs, they should easily meet your
requirements.
If you're looking for an industrial timer that can control other devices,
then you need to specify what kind of equipment or the power requirements of
the equipment.
--
Dave M
MasonDG44 at comcast dot net (Just subsitute the appropriate characters in
the address)
Never take a laxative and a sleeping pill at the same time!!
Roger Hamlett
Crystals, can relatively easily get to 1ppm. (you need just slightly
better than this), and with a crystal oven to control the temperature,
accuracies better that 0.1ppm, are relatively easy. Omega offer off the
shelf timing systems warranted to better than this.
Some radio transmitters in most countries have warranted accuracies
(usually on the long-wave), and a receiver, with a PLL locked onto this
can give superb accuracies (some warrant 0.01ppm, and some go even
further - in the UK, the 60KHz used for this, is maintained to better that
2 parts in 10^12). In the US, WWVB, broadcasts a similar signal.
These same transmitters are usually the ones carrying MSF time and date
information, and the master source is usually now an atomic clock. Some of
the receiver systems for these, have inputs for the distance to the
transmitter, and give 'real time', compensated for this to mSec or better
accuracies.
The master clock for the GPS system, provides similar accuracies. A
receiver, with local PLL, can be used again to get access to this clock.
Mains provides good 'long term' accuracy, but in the short term is poor,
and would not meet your requirements in this regard.
So, if you have access to radio reception, look at using a local
oscillator locked to the WWVB transmissions. Otherwise you will need to
consider a high accuracy crystal, in a suitable oven. If internet
connectivity is available, you could use a time server, and a local clock
slaved to this (units to do this are off the sheld items).
In the UK, one of th companies doing a range of products using these
technologies, are:
http://www.steatite.co.uk/downloads/time_freq_linecard.pdf
Best Wishes
Joerg
> Can I get recomendations for the most accurate electronic timer that I
> can buy?
>
> It must to be accurate to within 1/60th of a second over the course of
> 6 hours.
This lets me assume that you need some kind of electronic triggering.
1/60th of a second is to precise for a finger to push a button.
> Is something like this commercially available, or will I have to build
> it, or have someone build it?
Check out the sports markets. The devices for swimming relay contests
may not quite offer 6 hours but equipment for marathons or triathlons
should. It has been a while since I did competition swimming but I
vaguely remember that the stuff mostly came from the major watch
companies, usually from Switzerland.
Regards, Joerg
Jonathan Kirwan
I had thought that maintaining an accumulated deviation of no greater
than 1/60 sec in 6 hours is about like 24 seconds/year or 2 seconds a
month. This is <1ppm drift. Without being temperature stable, this
is not so easy, is it?
Jon
Mike Monett
>
> On Fri, 24 Jun 2005 16:36:09 -0400, "DaveM"
> <mason...@comcast99.net> wrote:
>
> ><Sear...@mail.con2.com> wrote
> >> Can I get recomendations for the most accurate electronic timer that I
> >> can buy?
> >>
> >> It must to be accurate to within 1/60th of a second over the course of
> >> 6 hours.
> >>
> >> Is something like this commercially available, or will I have to build
> >> it, or have someone build it?
> >>
> >> Any advice would be appreciated.
> >>
> >> Thanks a lot.
> >>
> >> Darren Harris
> >> Staten Island, New York.
[...]
> I had thought that maintaining an accumulated deviation of no greater
> than 1/60 sec in 6 hours is about like 24 seconds/year or 2 seconds a
> month. This is <1ppm drift. Without being temperature stable, this
> is not so easy, is it?
>
> Jon
Just checking the math: 1/(6*3600*60)=7.716E-7
You are right. That may be difficult without an oven.
Darren's spec may be a little tight. Normally, people who need to measure to
that precision already know the methods and where to get the needed
equipment.
The next question : what is he measuring that is that stable? I don't know of
anything that is expressed in seconds with <1ppm stability, except perhaps
gps. But if it involved gps, he'd already have the answer to his question.
Mike Monett
quietguy
timer woul dhave to have a readout in the order of 1/100's of a second.
Since this sort of accuracy is common in timing many sporting events (eg
swimming, motor racing, running etc) a chat with the local swimming club
etc might give you some leads to sources
David
NSM
> Can I get recomendations for the most accurate electronic timer that I
> can buy?
>
> It must to be accurate to within 1/60th of a second over the course of
> 6 hours.
You can pick up a Radio Shack Model 100 from $5 and up on eBay. There is
free software that will give you 8 separate accurate lap timers on that, one
for each function key. It runs off 4 AA cells.
N
Don Lancaster
6 hours would be 6 x 3600 x60 units = 1,296,000 or better than one part
in 10^6.
That is heading into TCXO crystal oven country.
Or possibly locking to a NIST radio source such as WWV or WWVB.
Or, at the very least, a calibration from a traceable source.
Loosen your spec.
--
Many thanks,
Don Lancaster
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
voice: (928)428-4073 email: d...@tinaja.com
Please visit my GURU's LAIR web site at http://www.tinaja.com
Jim Adney
<jki...@easystreet.com> wrote:
>I had thought that maintaining an accumulated deviation of no greater
>than 1/60 sec in 6 hours is about like 24 seconds/year or 2 seconds a
>month. This is <1ppm drift. Without being temperature stable, this
>is not so easy, is it?
It's about one part in 13 million, so, yes, this is pretty difficult.
You won't do this with a straight crystal oscillator, and I don't know
if any of the GPS units actually give out a clock signal that's fast
enough to measure 1/60 of a second.
HP makes a 10 MHz ovenized crystal oscillator which is much more
stable than this, however. There is one on ebay now for about $85.
That's about as cheap as you are likely to find for this level of
precision.
Do you really need this much precision?
-
-----------------------------------------------
Jim Adney jad...@vwtype3.org
Madison, WI 53711 USA
-----------------------------------------------
Richard H.
> Can I get recomendations for the most accurate electronic timer that I
> can buy?
>
> It must to be accurate to within 1/60th of a second over the course of
> 6 hours.
>
> Is something like this commercially available, or will I have to build
> it, or have someone build it?
You will certainly find what you need here, though whether it is within
your budget may be another matter. They have units that are far better
than 1ppm accurate. http://www.symmttm.com/
Or, have you considered a simple PC application that syncs its time from
NIST via the Internet using an NTP client? Virtually free and accurate
to <10ms, as long as you can tolerate a net-connected PC.
Or, perhaps a PC / system connected to a GPS receiver via the serial
port (though I understand the time via the serial port may only have
1-second resolution for many units, so homework is in order).
Richard
mike
Once you have this precision, you need some way to reliably use it.
I always get a chuckle out of "Star Trek". They've got massive
computers calculating precise timing, trajectories etc.
but they always initiate it with an imprecise verbal command, "ENGAGE".
mike
--
Return address is VALID but some sites block emails
with links. Delete this sig when replying.
.
Wanted, PCMCIA SCSI Card for HP m820 CDRW.
FS 500MHz Tek DSOscilloscope TDS540 Make Offer
Wanted 12" LCD for Compaq Armada 7770MT.
Bunch of stuff For Sale and Wanted at the link below.
MAKE THE OBVIOUS CHANGES TO THE LINK
ht<removethis>tp://www.geocities.com/SiliconValley/Monitor/4710/
Glenn Gundlach
I'm sitting here looking at my homebuilt digital clock that is counting
120 zero crosses of the AC line as its 1 second time base. Motorola
processor. Do you need the absolute accuracy or would counting
2,592,000 AC zero crosses do the trick?
GG
Dave Plowman (News)
Glenn Gundlach <stra...@yahoo.com> wrote:
> I'm sitting here looking at my homebuilt digital clock that is counting
> 120 zero crosses of the AC line as its 1 second time base. Motorola
> processor. Do you need the absolute accuracy or would counting
> 2,592,000 AC zero crosses do the trick?
In the UK, the mains frequency might well average out at 50 Hz over 24
hours, but that's not the same as being absolutely accurate over any 6
hour period. Can't see the US being any different.
--
*The man who fell into an upholstery machine is fully recovered.*
Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.
NSM
"mike" <spa...@netscape.net> wrote in message
news:42BCD8EB...@netscape.net...
> Once you have this precision, you need some way to reliably use it.
>
> I always get a chuckle out of "Star Trek". They've got massive
> computers calculating precise timing, trajectories etc.
> but they always initiate it with an imprecise verbal command, "ENGAGE".
Hard to take a show seriously where spacecraft make banking turns in space
and go "Whoosh" as they pass you. "Blake's 7" at least got that part right.
N
Sear...@mail.con2.com
I originally entertained something like this 2-1/2 years ago, but the
timer I needed, which was basically a racing watch, but with a large
bright red display, was not commercially available and proved too
complicated to build.
So I have to settle on just a simple timer for now, and worry about
getting something more complex later.
It is way too complicated to go into the details as far as why I need
this, but basically this will involve conducting experiments/tests on
the accuracy of human timing, and also the confirmation of certain
conclusions drawn from studying the code contained within the hardware
I'll be testing against.
1/60th of a second is important because it is specific to that hardware
and how it functions. It uses registers that change every 1/60th of a
second to make certain occurances "random". If one could react with an
accuracy of 1/60th of a second, then these occurances would follow a
predictable pattern. But of course that kind of timing is not humanly
possible with any kind of consistency.
Anyway, to simplify what I'm doing, this involves a huge number of
timed inputs(by a person) over the course of several hours. The timer
will be the reference.
If it is easier for me to get a set-up that involves frequent
resets/corrections to get the needed accuracy at any 60th of a second
over the course of several hours, then that is what I'll have to do.
P.S: The hardware itself is a videogame.
Richard H.
> 1/60th of a second is important because it is specific to that hardware
> and how it functions. It uses registers that change every 1/60th of a
> second to make certain occurances "random". If one could react with an
> accuracy of 1/60th of a second, then these occurances would follow a
> predictable pattern. But of course that kind of timing is not humanly
> possible with any kind of consistency.
>
> Anyway, to simplify what I'm doing, this involves a huge number of
> timed inputs(by a person) over the course of several hours. The timer
> will be the reference.
>
> If it is easier for me to get a set-up that involves frequent
> resets/corrections to get the needed accuracy at any 60th of a second
> over the course of several hours, then that is what I'll have to do.
>
> P.S: The hardware itself is a videogame.
This strikes me as a very different definition of the problem from your
original post...
If your goal is to have an event 60 times per second with good accuracy,
that is trivial with most microcontrollers. Even a basic design could
get you 100,000 events per second with good accuracy.
But what you described in your original post was a requirement to finish
after 6 hours with a clock drift of no more than 1/60 second. That
problem is 21,600 times harder, and requires elaborate solutions.
i.e., it sounds like your requirement is for a timer that can:
a) trigger 60 times per second with "good" accuracy
b) count for 6 hours or more
In defining "good" accuracy, 1% equates to +/- 0.00017 secs margin per
60/sec event (between 0.01649 and 0.01683 seconds per event). These
timings aren't likely to vary much on one board (barring temerature
changes), but would vary in this range from one board to the next.
So, what degree of accuracy are you really needing?
Cheers,
Richard
Sear...@mail.con2.com
Richard H. wrote:
> Sear...@mail.con2.com wrote:
> > 1/60th of a second is important because it is specific to that hardware
> > and how it functions. It uses registers that change every 1/60th of a
> > second to make certain occurances "random". If one could react with an
> > accuracy of 1/60th of a second, then these occurances would follow a
> > predictable pattern. But of course that kind of timing is not humanly
> > possible with any kind of consistency.
> >
> > Anyway, to simplify what I'm doing, this involves a huge number of
> > timed inputs(by a person) over the course of several hours. The timer
> > will be the reference.
> >
> > If it is easier for me to get a set-up that involves frequent
> > resets/corrections to get the needed accuracy at any 60th of a second
> > over the course of several hours, then that is what I'll have to do.
> >
> > P.S: The hardware itself is a videogame.
>
> This strikes me as a very different definition of the problem from your
> original post...
How? In my original post I said the following: "It must to be accurate
to within 1/60th of a second over the course of 6 hours."
> If your goal is to have an event 60 times per second with good accuracy,
> that is trivial with most microcontrollers. Even a basic design could
> get you 100,000 events per second with good accuracy.
But that is not my goal.
> But what you described in your original post was a requirement to finish
> after 6 hours with a clock drift of no more than 1/60 second. That
> problem is 21,600 times harder, and requires elaborate solutions.
>
> i.e., it sounds like your requirement is for a timer that can:
> a) trigger 60 times per second with "good" accuracy
> b) count for 6 hours or more
Still wrong. The timer will trigger nothing. All it needs is a display
so that I can see the seconds.(Though showing 1/60th of a second
intervals would be great, it's just not required for this project,
which I have had to simplify greatly).
> In defining "good" accuracy, 1% equates to +/- 0.00017 secs margin per
> 60/sec event (between 0.01649 and 0.01683 seconds per event). These
> timings aren't likely to vary much on one board (barring temerature
> changes), but would vary in this range from one board to the next.
>
> So, what degree of accuracy are you really needing?
1/60th of a second...
(ie: When the 2 hour, 53 minute, and 37 second point is reached, the
display should show it at exactly that time at an accuracy of 1/60th of
a second from when the clock started running).
Mike Monett
[...]
> > So, what degree of accuracy are you really needing?
>
> 1/60th of a second...
>
> (ie: When the 2 hour, 53 minute, and 37 second point is reached, the
> display should show it at exactly that time at an accuracy of 1/60th of
> a second from when the clock started running).
>
> Darren Harris
> Staten Island, New York.
You have no idea what your requirements mean. A drift of 1ppm in 6 hrs is
meaningless in a marathon or other race, when the wind can easily cause
1% change in performance.
So in Brooklanese -Fahgettaboutit!
Mike Monett
Sear...@mail.con2.com
There is no wind involved here.
I've been trying not to get into the details, because details lead to
the request for more details, and this is just way to complex to get
into here. Not just as far as what I'm doing, but the timer I am
seeking is actually inadequate for all of the experiments I want to do.
Now if this is so difficult to understand, then the more complex timer
will be near impossible to explain.
For this project there will be 1,296,000 increments over the course of
6 hours. I just need the option of *visually* seeing on the timer's
display when each second increments beginning with the press of a start
button, and the accuracy must be 1/60th of a second at worst for any of
those 21,600 seconds after zero.(I'm assuming that the timer will have
to be plugged in an AC outlet).
Mike Monett
[...]
> I've been trying not to get into the details, because details lead to
> the request for more details, and this is just way to complex to get
> into here. Not just as far as what I'm doing, but the timer I am
> seeking is actually inadequate for all of the experiments I want to do.
>
> Now if this is so difficult to understand, then the more complex timer
> will be near impossible to explain.
I think you just lost the interest of anyone capable of helping you.
> For this project there will be 1,296,000 increments over the course of
> 6 hours. I just need the option of *visually* seeing on the timer's
> display when each second increments beginning with the press of a start
> button, and the accuracy must be 1/60th of a second at worst for any of
> those 21,600 seconds after zero.(I'm assuming that the timer will have
> to be plugged in an AC outlet).
>
> Darren Harris
> Staten Island, New York.
The truth you seek is out there. Have fun:)
Mike Monett
quietguy
> Actually, since your application is only a video game, then perhaps it is
> not accuracy that you need - rather precision, which is a very different
> concept to accuracy.
Have a think about it and perhaps that will simplify your problem
David
Sear...@mail.con2.com
Well compensating for centrifugal force is plausible, and space is not
a complete vacuum. :-)
Sear...@mail.con2.com
quietguy wrote:
> >
> > Actually, since your application is only a video game, then perhaps it is
> > not accuracy that you need - rather precision, which is a very different
> > concept to accuracy.
No. I'm sure that accuracy is definitely what is needed.
> Have a think about it and perhaps that will simplify your problem
The problem is what it is. There is nothing that can be changed.
Obviously, even this simple version of a timer is not commercially
available, and not something that can be easily built.
Thanks.
Jim Adney
wrote:
>On Fri, 24 Jun 2005 20:59:10 GMT Jonathan Kirwan
><jki...@easystreet.com> wrote:
>
>>I had thought that maintaining an accumulated deviation of no greater
>>than 1/60 sec in 6 hours is about like 24 seconds/year or 2 seconds a
>>month. This is <1ppm drift. Without being temperature stable, this
>>is not so easy, is it?
>
>It's about one part in 13 million, so, yes, this is pretty difficult.
Oops, I'm off by one decimal place; it's more like one part in 1.3
million. This can be done with a good crystal oscillator, but it's got
to be a pretty good one, and it has to be calibrated against a real
standard.
The question remains of why one would need this degree of accuracy in
a timing function.
James Waldby
> > > > So, what degree of accuracy are you really needing?
> > >
> > > 1/60th of a second...
> > >
> > > (ie: When the 2 hour, 53 minute, and 37 second point is reached, the
> > > display should show it at exactly that time at an accuracy of 1/60th of
> > > a second from when the clock started running).
> > You have no idea what your requirements mean. A drift of 1ppm in 6 hrs is
> > meaningless in a marathon or other race, when the wind can easily cause
> > 1% change in performance.
> I've been trying not to get into the details, because details lead to
> the request for more details, and this is just way to complex to get
> into here. Not just as far as what I'm doing, but the timer I am
> seeking is actually inadequate for all of the experiments I want to do.
You will waste a lot less of everyone's time if you just go ahead
and explain what you want. If you happen to know. Of course if you
don't know what you want, you are less likely to get it.
Anyhow, AIUI you have a video game and you want to use a timer for
doing something related to this game ... perhaps you want to reverse
engineer it, perhaps crack some protection, perhaps set up a computer-
aided play device. Whatever. And you think that having a timer with
1/60 second accuracy displaying the current time throughout a six hour
period will help you do so. (It may be silly for you to think so, because
if you are just reading the time off the running display or pushing
buttons to record the time when stuff happens, you won't be able to do
either one with 1/60 second reaction times anyway.)
Note that the clock in the video game almost certainly will drift
around in a range at least 10 parts per million wide, which makes
your 1 ppm requirement superfluous. Instead, snoop the video game
clock and use a buffered copy of it to drive the counters in your timer.
This way your displayed time always is in sync with the video game time.
> Now if this is so difficult to understand, then the more complex timer
> will be near impossible to explain.
Perhaps your problem is that you don't know what you are doing.
Feel free to convince us otherwise.
> For this project there will be 1,296,000 increments over the course of
> 6 hours. I just need the option of *visually* seeing on the timer's
> display when each second increments beginning with the press of a start
> button, and the accuracy must be 1/60th of a second at worst for any of
> those 21,600 seconds after zero.
As several people have noted, you could use a TXCO (temperature
compensated crystal oscillator) or a crystal oven for adequate
performance. See eg $4 and $18 items
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526666127
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526612301
Note that you can get an inexpensive counter/timer on ebay, like
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526025102
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526108906
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526165454
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526085126
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526393893
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7525744632
The bench instruments probably have 7 to 10 digit stability
when warmed up and similar accuracy when in cal. Some of them
might make their timebases externally available and/or have
totalizer functions that would do the job for you. In any case,
if you build a TXCO you'll need a counter/timer to check it.
-jiw
Richard H.
> I've been trying not to get into the details, because details lead to
> the request for more details, and this is just way to complex to get
> into here.
Darren,
You are correct that it takes details to provide a useful answer. Based
on the broad question originally asked, the URL I provided should have
met your needs. Perhaps if we understood why you didn't find what you
needed there, more accurate responses might be possible.
If you work with engineers much, you'll appreciate that people very
often ask for the wrong thing - by challenging questionable requirements
the true specs become known, often hugely affecting the complexity
involved. Here, you are asking for a degree of accuracy that is
difficult to achieve, but you say you won't actually be using it, which
sounds flawed. (Irrespective of the event frequency in the DUT, if you
are only capturing one-second granularity, more accuracy is wasted.)
> ... the timer I am
> seeking is actually inadequate for all of the experiments I want to do.
>
> Now if this is so difficult to understand, then the more complex timer
> will be near impossible to explain.
So, you're wasting everyone's time (including yours) looking for a
solution that won't meet your needs? If you really want nanosecond
accuracy, we can guide you to a solution that'd give you that, but not
if you don't ask.
If you would be less defensive about the requirements and share more
about your desired goal, you might get help in meeting it - the volume
of responses here demonstrates folks' willingness to help. We don't
need you to divulge your experiment, but significant requirements would
be nice (budget, size, weight, power, connectivity, inputs, outputs,
skillset), along with some tolerance for validating the potentially
difficult specs.
All that said, have you considered the overly simple solution of
software on a PC? It may be difficult to get better than 18.2ms
resolution from the system clock, but that is very close to your stated
requirement, and an RTC clock card would be easy enough to add.
Then, use SNTP to frequently check an atomic source and factor the drift
into the local clock's readings. (Or ditch the local clock entirely and
just make an SNTP/Daytime query of an atomic clock at the time you want
a reading - the accuracy can be calc'd as good as 1/250 sec.) Plus,
this is easily extensible to integrate with an event log, rather than
using a manual process.
Of course, there's no knowing if this will meet your other unstated
requirements, so perhaps it was a waste of time to share this idea?
Richard
maa...@panic.xx.tudelft.nl
> The problem is what it is. There is nothing that can be changed.
If, even with expert help, a problem appears to be hard or expensive to
solve, change the problem. Every engineer has done that at least one but
probably several times...
---
Met vriendelijke groet,
Maarten Bakker.
Sear...@mail.con2.com
> and explain what you want. If you happen to know. Of course if you
> don't know what you want, you are less likely to get it.
I said in my very first post that I was looking for an electronic timer
that is accurate to within 1/60th of a second over the course of 6
hours. Then the thread turned into questions concerning my project and
assumptions as to why what I ask for wasn't logical.
> Anyhow, AIUI you have a video game and you want to use a timer for
> doing something related to this game ... perhaps you want to reverse
> engineer it, perhaps crack some protection, perhaps set up a computer-
> aided play device. Whatever. And you think that having a timer with
> 1/60 second accuracy displaying the current time throughout a six hour
> period will help you do so. (It may be silly for you to think so, because
> if you are just reading the time off the running display or pushing
> buttons to record the time when stuff happens, you won't be able to do
> either one with 1/60 second reaction times anyway.)
I did previously say: "But of course that kind of timing is not humanly
possible with any kind of consistency."
> Note that the clock in the video game almost certainly will drift
> around in a range at least 10 parts per million wide, which makes
> your 1 ppm requirement superfluous. Instead, snoop the video game
> clock and use a buffered copy of it to drive the counters in your timer.
> This way your displayed time always is in sync with the video game time.
I'm aware of the consistency of the game hardware. And this project
can't involve tapping into the games clock.
> > Now if this is so difficult to understand, then the more complex timer
> > will be near impossible to explain.
>
> Perhaps your problem is that you don't know what you are doing.
> Feel free to convince us otherwise.
The problem is the criticizing of my needs and the suggestion of
alternatives by those unfamiliar with the project. The initial question
was simple, and I thank those who gave me their best answers.
> > For this project there will be 1,296,000 increments over the course of
> > 6 hours. I just need the option of *visually* seeing on the timer's
> > display when each second increments beginning with the press of a start
> > button, and the accuracy must be 1/60th of a second at worst for any of
> > those 21,600 seconds after zero.
>
> As several people have noted, you could use a TXCO (temperature
> compensated crystal oscillator) or a crystal oven for adequate
> performance. See eg $4 and $18 items
> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526666127
> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526612301
>
> Note that you can get an inexpensive counter/timer on ebay, like
> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526025102
> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526108906
> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526165454
> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526085126
> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526393893
> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7525744632
> The bench instruments probably have 7 to 10 digit stability
> when warmed up and similar accuracy when in cal. Some of them
> might make their timebases externally available and/or have
> totalizer functions that would do the job for you. In any case,
> if you build a TXCO you'll need a counter/timer to check it.
> -jiw
I'm just looking for a timer to click off every second on it's display,
and with the accuracy I mentioned. I know nothing about how to build
anything, or about the features of the devices in those links.
Sear...@mail.con2.com
Richard H. wrote:
> Sear...@mail.con2.com wrote:
> > I've been trying not to get into the details, because details lead to
> > the request for more details, and this is just way to complex to get
> > into here.
>
> Darren,
>
> You are correct that it takes details to provide a useful answer. Based
> on the broad question originally asked, the URL I provided should have
> met your needs. Perhaps if we understood why you didn't find what you
> needed there, more accurate responses might be possible.
> If you work with engineers much, you'll appreciate that people very
> often ask for the wrong thing - by challenging questionable requirements
> the true specs become known, often hugely affecting the complexity
> involved. Here, you are asking for a degree of accuracy that is
> difficult to achieve, but you say you won't actually be using it, which
> sounds flawed. (Irrespective of the event frequency in the DUT, if you
> are only capturing one-second granularity, more accuracy is wasted.)
I'm not asking for the wrong thing. The requirements are only
"questionable to someone not familiar to with what I am trying to do. I
never said that I will not be using the accuracy I am searching for.
And I think it has already been established that the kind of accurate
timer I need doesn't exist(or no one here knows of one).
>
> > ... the timer I am
> > seeking is actually inadequate for all of the experiments I want to do.
> >
> > Now if this is so difficult to understand, then the more complex timer
> > will be near impossible to explain.
>
> So, you're wasting everyone's time (including yours) looking for a
> solution that won't meet your needs? If you really want nanosecond
> accuracy, we can guide you to a solution that'd give you that, but not
> if you don't ask.
Who said that I'm looking for a solution that won't meet my needs?(And
I only need 1/60th of a second acccuracy).
> If you would be less defensive about the requirements and share more
> about your desired goal, you might get help in meeting it - the volume
> of responses here demonstrates folks' willingness to help. We don't
> need you to divulge your experiment, but significant requirements would
> be nice (budget, size, weight, power, connectivity, inputs, outputs,
> skillset), along with some tolerance for validating the potentially
> difficult specs.
All this is unecessary info for a timer with a simple read-out. There
are no other rquirements than what I stated.
> All that said, have you considered the overly simple solution of
> software on a PC? It may be difficult to get better than 18.2ms
> resolution from the system clock, but that is very close to your stated
> requirement, and an RTC clock card would be easy enough to add.
Again, I need only 1/60th of a second accuracy, and the reference point
will be from "start".
> Then, use SNTP to frequently check an atomic source and factor the drift
> into the local clock's readings. (Or ditch the local clock entirely and
> just make an SNTP/Daytime query of an atomic clock at the time you want
> a reading - the accuracy can be calc'd as good as 1/250 sec.) Plus,
> this is easily extensible to integrate with an event log, rather than
> using a manual process.
>
> Of course, there's no knowing if this will meet your other unstated
> requirements, so perhaps it was a waste of time to share this idea?
Yeah. I guess I'll have to look elsewhere.
Thanks.
Sear...@mail.con2.com
quietguy wrote:
> >
> > Actually, since your application is only a video game, then perhaps it is
> > not accuracy that you need - rather precision, which is a very different
> > concept to accuracy.
>
> Have a think about it and perhaps that will simplify your problem
The problem is getting a timer.
Sear...@mail.con2.com
maa...@panic.xx.tudelft.nl wrote:
> In sci.electronics.repair Sear...@mail.con2.com wrote:
> > The problem is what it is. There is nothing that can be changed.
>
> If, even with expert help, a problem appears to be hard or expensive to
> solve, change the problem. Every engineer has done that at least one but
> probably several times...
I've already simplified the timer requirements so as to target part of
my "problem".
John Fields
>The problem is getting a timer.
---
I can build exactly what you want. Email me if you're interested with
how much you're prepared to spend to get it.
--
John Fields
Professional Circuit Designer
Jim Adney
>The problem is getting a timer.
You've said that you just want a timer that will run over a period of
six hours with 1/60 sec accuracy.
You've said that all you want is a simple clock display that reads out
seconds.
You've said that it needs to just start at an arbitrary start time and
count from there.
None of these goals is particularly hard, but to get that accuracy
you'll need to buy some sort of commercial clock with a time display
and mate it to a frequency source (which in this industry is also
commonly called a "clock", further confusing this question) that is
more accurate than such timers usually come with. Or, if you have real
money to spend you can buy something with a real frequency standard
(clock) inside which could be purchased with a digital clock display.
The price for something like this could be anything from $2500 to
$40,000. This whole range is much more accurate than you've asked for,
but it seems unlikely that anyone makes something that meets just your
minimum accuracy requirement.
The problem that I see is that you've not asked for any kind of
electronic input or output for the timer, which makes most of us
wonder how you expect to be able to use 1/60 sec accuracy while just
doing this by eye.
If you're planning to use electronic start and stop signals, then you
can get much better accuracy than 1/60 sec.
So this leaves us confused about what it is that you really want/need.
It's not that people here are trying to be difficult; it's that they
are trying to be helpful, but the specs of your request, taken as a
whole, just don't seem to make sense.
So if you explained a little more, without giving away any of your
secrets, then you will probably get the answer you're after.
Richard H.
> And I think it has already been established that the kind of accurate
> timer I need doesn't exist(or no one here knows of one).
http://www.google.com/search?q=1%2F100+second+timer
#2 on the list...
http://www.meylan.com/1_100sec.html
12 models with 1/100 displays and up to 100 hours. Whether they're
really 99.99992%+ accurate is for you to determine.
Now, these were very easy to find. They meet your limited "simple"
specs. Seiko is a name brand in sports timing, and the printer model
has it all.
I'll politely assume that surely you searched Google first, found these,
and determined they were inadequate by merely looking at them. So, what
makes these unsuitable?
Richard
Sear...@mail.con2.com
Well, you have already hinted at it yourself.
What are the odds that a stand alone stopwatch will be anything close
to 1/60th of a second of the correct time at the 6 hour mark?
And we all know that 1/100th of a second on a hand held stopwatch is
nothing but a marketing gimic. :-)
Sear...@mail.con2.com
Jim Adney wrote:
> On 27 Jun 2005 10:09:50 -0700 Sear...@mail.con2.com wrote:
>
> >The problem is getting a timer.
>
> You've said that you just want a timer that will run over a period of
> six hours with 1/60 sec accuracy.
>
> You've said that all you want is a simple clock display that reads out
> seconds.
>
> You've said that it needs to just start at an arbitrary start time and
> count from there.
Yup.
> None of these goals is particularly hard, but to get that accuracy
> you'll need to buy some sort of commercial clock with a time display
> and mate it to a frequency source (which in this industry is also
> commonly called a "clock", further confusing this question) that is
> more accurate than such timers usually come with. Or, if you have real
> money to spend you can buy something with a real frequency standard
> (clock) inside which could be purchased with a digital clock display.
> The price for something like this could be anything from $2500 to
> $40,000. This whole range is much more accurate than you've asked for,
> but it seems unlikely that anyone makes something that meets just your
> minimum accuracy requirement.
So it seems. :-)
> The problem that I see is that you've not asked for any kind of
> electronic input or output for the timer, which makes most of us
> wonder how you expect to be able to use 1/60 sec accuracy while just
> doing this by eye.
Let me repost something I wrote earlier in this thread:
"It is way too complicated to go into the details as far as why I need
this, but basically this will involve conducting experiments/tests on
the accuracy of human timing, and also the confirmation of certain
conclusions drawn from studying the code contained within the hardware
I'll be testing against."
"1/60th of a second is important because it is specific to that
hardware
and how it functions. It uses registers that change every 1/60th of a
second to make certain occurances "random". If one could react with an
accuracy of 1/60th of a second, then these occurances would follow a
predictable pattern. But of course that kind of timing is not humanly
possible with any kind of consistency."
> If you're planning to use electronic start and stop signals, then you
> can get much better accuracy than 1/60 sec.
Again, this involves "human timing".
> So this leaves us confused about what it is that you really want/need.
> It's not that people here are trying to be difficult; it's that they
> are trying to be helpful, but the specs of your request, taken as a
> whole, just don't seem to make sense.
I covered everything pertinent in my posts, and have no idea what else
I can say(that doesn't throw everyone further into a state of
cconfusion).
> So if you explained a little more, without giving away any of your
> secrets, then you will probably get the answer you're after.
There are no "secrets".
This is actually much simpler than the original project which involves
more than just a timer, but the ability to record the time of each of
four (joystick)input activations/deactivations, which could number over
300 over the course of between 2 and 3 minutes. And then play them back
the same way.(Thereby replicating my moves with that 1/60th of a second
accuracy). But since I am having such difficulty with this, the
original needs are definitely out of the question anytime soon.
I thought that there might be an affordable timer that would somehow
keep it's accuracy by via 60Hertz AC. But I guess not.
biltu
Ian Stirling wrote:
> In sci.electronics.design Sear...@mail.con2.com wrote:
> > Can I get recomendations for the most accurate electronic timer that I
> > can buy?
> >
> > It must to be accurate to within 1/60th of a second over the course of
> > 6 hours.
> >
> > Is something like this commercially available, or will I have to build
> > it, or have someone build it?
>
> GPS recievers.
> I've seen some with an alarm function.
> However, 1/60th of a second in 6 hours isn't impossible to do otherwise.
maa...@panic.xx.tudelft.nl
> None of these goals is particularly hard, but to get that accuracy
> you'll need to buy some sort of commercial clock with a time display
> and mate it to a frequency source (which in this industry is also
> commonly called a "clock", further confusing this question) that is
> more accurate than such timers usually come with. Or, if you have real
> money to spend you can buy something with a real frequency standard
> (clock) inside which could be purchased with a digital clock display.
> The price for something like this could be anything from $2500 to
> $40,000. This whole range is much more accurate than you've asked for,
> but it seems unlikely that anyone makes something that meets just your
> minimum accuracy requirement.
As said before, the power company has something almost up to that
standard, but that idea was probably also rejected in earlier
discussion here?
Ian Stirling
<snip>
> Well, you have already hinted at it yourself.
>
> What are the odds that a stand alone stopwatch will be anything close
> to 1/60th of a second of the correct time at the 6 hour mark?
>
>
> And we all know that 1/100th of a second on a hand held stopwatch is
> nothing but a marketing gimic. :-)
Google
GPS stopwatch
Job done.
Rich Grise
[and seems to have snipped all attribution]
>> > Now if this is so difficult to understand, then the more complex timer
>> > will be near impossible to explain.
>>
>> Perhaps your problem is that you don't know what you are doing.
>> Feel free to convince us otherwise.
>
> The problem is the criticizing of my needs and the suggestion of
> alternatives by those unfamiliar with the project. The initial question
> was simple, and I thank those who gave me their best answers.
We are "unfamiliar with the project" because you haven't _told_ us
anything about the project. You've made some obscure reference to
video games;
What do you need to time?
What are you trying to accomplish?
Yeah, the question was simple. "I need to time an interval to an
accuracy of 1/60 second, over a span of possibly 6 hours."
People who have many years' experience have informed you of almost
a half-dozen ways to accomplish this, but apparently they're
unsatisfactory.
And newbies wonder why us crusty old farts get annoyed at newbies.
Get to the f---ing point, rather than bitching about the suggestions
that have been offered based on nothing more than the above, with
a dollop of mind reading thrown in. In Other Words, What Are You
Trying To Accomplish?
Thanks,
Rich
Rich Grise
> On 27 Jun 2005 10:09:50 -0700, Sear...@mail.con2.com wrote:
>
>>The problem is getting a timer.
>
> ---
> I can build exactly what you want. Email me if you're interested with
> how much you're prepared to spend to get it.
Me Too!
;-)
Rich
BTW, the email is richardgrise at yahoo dot com, but elide ard.
Rich Grise
> This is actually much simpler than the original project which involves
> more than just a timer, but the ability to record the time of each of
> four (joystick)input activations/deactivations, which could number over
> 300 over the course of between 2 and 3 minutes. And then play them back
> the same way.(Thereby replicating my moves with that 1/60th of a second
> accuracy). But since I am having such difficulty with this, the
> original needs are definitely out of the question anytime soon.
Well, Jesus Aitch! Why didn't you just say so? There's probably a
dozen people here who could design a joystick tracker with millisecond
accuracy, and record switch closures to microsecond tolerances. I'd
lighten up a bit on looking for a coincidence detector, which is not
going to happen unless you can physically hack the game you're trying
to hack.
If you're looking at reaction time stuff, then you'll have to find
a biology or anatomy group, although I'd still venture to guess that
most people who are conversant with this level of electronics
probably know something about nerve impulse propagation and
electromyelographic interfaces. Heck, a year or so ago, I was being
tested for neuropathy, and they taped some electrodes that look
very much like EKG or EEG electrodes to my legs, and the nurse (or
lady doctor - we didn't get into that) took a hand-held that looked
so much like a stun gun that when I said, "Stun Gun???" she said,
"That's what everybody says." They stunned me, and they took
readings of my neural response. Diagnosis: Alcoholic Neuropathy.
Oh, well.
You might also look into the source code for "MAME" - Multiple
Arcade Machine Emulator. I play Mr. Do! and Bubble Bobble regularly,
and am considering something much like your project, to see how the
software uses joystick/button actions to modify its own algorithm!
Good Luck!
Rich
maa...@panic.xx.tudelft.nl
> I said in my very first post that I was looking for an electronic timer
> that is accurate to within 1/60th of a second over the course of 6
> hours. Then the thread turned into questions concerning my project and
> assumptions as to why what I ask for wasn't logical.
I think for you to measure an event with an accuracy of 1/60th of a
second, you need to take measurements at least 120 times a second (well
known theorem, I forgot the name).
OBones
That would be Shannon.
Keith Williams
obones_gfd_@_gfd_altern.org says...
bandwidth and S/N ratio.
--
Keith
Richard Henry
<maa...@panic.xx.tudelft.nl> wrote in message
news:5e1c2$42c1a90b$82a12456$29...@news1.tudelft.nl...
Nyquist.
quietguy
better way to go, but the guy rejects this idea, but I agree it is a better shot
David
Sear...@mail.con2.com
Rich Grise wrote:
> On Mon, 27 Jun 2005 23:00:46 -0700, Searcher7 wrote:
>
> > This is actually much simpler than the original project which involves
> > more than just a timer, but the ability to record the time of each of
> > four (joystick)input activations/deactivations, which could number over
> > 300 over the course of between 2 and 3 minutes. And then play them back
> > the same way.(Thereby replicating my moves with that 1/60th of a second
> > accuracy). But since I am having such difficulty with this, the
> > original needs are definitely out of the question anytime soon.
>
> Well, Jesus Aitch! Why didn't you just say so? There's probably a
> dozen people here who could design a joystick tracker with millisecond
> accuracy, and record switch closures to microsecond tolerances. I'd
> lighten up a bit on looking for a coincidence detector, which is not
> going to happen unless you can physically hack the game you're trying
> to hack.
As I mentioned, I can't hack into the gameboard. This has to be a
separate device. And this project is on the back burner anyway, since
it is more complex than just the timer I am seeking for now.
> If you're looking at reaction time stuff, then you'll have to find
> a biology or anatomy group, although I'd still venture to guess that
> most people who are conversant with this level of electronics
> probably know something about nerve impulse propagation and
> electromyelographic interfaces. Heck, a year or so ago, I was being
> tested for neuropathy, and they taped some electrodes that look
> very much like EKG or EEG electrodes to my legs, and the nurse (or
> lady doctor - we didn't get into that) took a hand-held that looked
> so much like a stun gun that when I said, "Stun Gun???" she said,
> "That's what everybody says." They stunned me, and they took
> readings of my neural response. Diagnosis: Alcoholic Neuropathy.
>
> Oh, well.
>
> You might also look into the source code for "MAME" - Multiple
> Arcade Machine Emulator. I play Mr. Do! and Bubble Bobble regularly,
> and am considering something much like your project, to see how the
> software uses joystick/button actions to modify its own algorithm!
MAME is not an option, because the original hardware must be used.
The original project involved a "Automatic Pattern Generator". People
develop patterns to clear the mazes in the game Pac-man. I wanted to
have a computer develop patterns through trial and error, but that
would entail hacking into the game board.
So I came up with the idea to at the press of a button have my joystick
movements recorded and then have the option of playing the sequence
back through the joystick inputs.(It's a lot more complex than this,
but those are the basics).
I've had to put these ideas on the back burner and concentrate on
something else that requires the timer I posted about.
Rich Grise
...
> So I came up with the idea to at the press of a button have my joystick
> movements recorded and then have the option of playing the sequence back
> through the joystick inputs.(It's a lot more complex than this, but
> those are the basics).
THIS IS ALMOST TRIVIAL TO DO!!!!!!!!!! Why are you so impelled to continue
to be a bonehead?
> I've had to put these ideas on the back burner and concentrate on
> something else that requires the timer I posted about.
People keep giving you answers, and you keep rejecting them - the only
logical conclusion is that you're doing nothing but trolling.
Sorry.
Rich
Sear...@mail.con2.com
I'm not the one trolling here.
None of that had to do with the original question which was for a
timer. And that's all.
I've got all of the answers I could get here.
Darren Harris
Staten ISland, New York.
John Fields
>In sci.electronics.repair Sear...@mail.con2.com wrote:
>> I've got all of the answers I could get here.
>
>But have you read them? Apart from that you may not be able to interpret
>them, I know you got some useful advise. I suggested you use an 120Hz
>clock, so you will actually obtain the sampling resolution you want. I
>have not seen you respond to that, thankful nor rejective. For me that
>implies you should really find an electronics designer to work with.
---
For me, your suggestion that he use a 120Hz clock implies that you
don't know what you're talking about.
Considering that the OP has specified that: "It must to be accurate
to within 1/60th of a second over the course of 6 hours."
means that, since there are 3600 seconds in an hour there will be
21,600 seconds in six hours, and since he wants to split the seconds
into 60 slivers each, there will be 1,296,000 slivers in six hours.
Since he states that the accuracy must be _within_ 1 sliver, that
means he needs an accuracy of one part in 1,296,000. Looking at it
from a different perspective, that's an accuracy of +/- 0.000038580%.
Now, what was it you were saying about that 120Hz clock?
maa...@panic.xx.tudelft.nl
> I've got all of the answers I could get here.
But have you read them? Apart from that you may not be able to interpret
them, I know you got some useful advise. I suggested you use an 120Hz
clock, so you will actually obtain the sampling resolution you want. I
have not seen you respond to that, thankful nor rejective. For me that
implies you should really find an electronics designer to work with.
---
James Waldby
I think "Hanlon's Razor", ie, "Never attribute to malice that which
is adequately explained by stupidity"* is a more-logical
explanation here, if we regard trolling as malicious and think of
ignorance/boneheadity/laziness/wrongheadedness as akin to stupidity.
It seems to me that Darren Harris has rejected out of hand most
suggestions because he failed to understand them.
-jiw
Guy Macon
Sear...@mail.con2.com wrote:
>
>Rich Grise wrote:
>
>> People keep giving you answers, and you keep rejecting them - the only
>> logical conclusion is that you're doing nothing but trolling.
>
>I'm not the one trolling here.
You certainly appear to be trolling.
>None of that had to do with the original question which was for a
>timer. And that's all.
Your original question was fully answered several times, as were
your followups where you kept adding details that you left out.
Please read this:
How To Ask Questions The Smart Way
http://www.catb.org/~esr/faqs/smart-questions.html
>I've got all of the answers I could get here.
I am no fan of the usual flamewars and topic drift here, but in
this case the fault is 100% yours. You won't get a good answer
anywhere else unless you read the above website and start following
the advice in it.
Followups set. If you don't know what that means, find out.
Sear...@mail.con2.com
The suggestion was faulty. That is why that post of his is now gone.
Sear...@mail.con2.com
Guy Macon wrote:
> Sear...@mail.con2.com wrote:
> >
> >Rich Grise wrote:
> >
> >> People keep giving you answers, and you keep rejecting them - the only
> >> logical conclusion is that you're doing nothing but trolling.
> >
> >I'm not the one trolling here.
>
> You certainly appear to be trolling.
Only to someone who doesn't know what trolling is.
> >None of that had to do with the original question which was for a
> >timer. And that's all.
>
> Your original question was fully answered several times, as were
> your followups where you kept adding details that you left out.
Totally incorrect. Find a single post in this thread where it was
answered completely.
And I added no details that I "left out". Those "follow ups" should not
have happened, since they were off post. But certain people kept
needling me for details.
> Please read this:
>
> How To Ask Questions The Smart Way
> http://www.catb.org/~esr/faqs/smart-questions.html
What for?
> >I've got all of the answers I could get here.
>
> I am no fan of the usual flamewars and topic drift here, but in
> this case the fault is 100% yours. You won't get a good answer
> anywhere else unless you read the above website and start following
> the advice in it.
>
> Followups set. If you don't know what that means, find out.
I don't need to read any such website.
The topic drift here is not my fault. Would it take a genius to answer
the question in the first post without needing more details?
Evidently so.
Again, I have whatever answers I can get here. Let it go.
Sear...@mail.con2.com
I rejected most suggestions because I did understand them,and they were
adequate for my needs. Only someone truly stupid would not understand
that.
Of those links that were posted, I have yet to hear back from the one
company I e-mailed. And the timers didn't have enough details or were
totally inadequate for my purposes.(Like those Ebay links you posted).
I read all the advice here and said thanks a several times throughout
the thread, and stated that I got all the info I could get here. What
else do you want from me? The crap is over details that certain
individuals are looking for. Those details are complicated and totally
off topic.
maa...@panic.xx.tudelft.nl
> Now, what was it you were saying about that 120Hz clock?
I was not presenting it as a complete solution, but as a useful part of
finding another strategy to solve the problem.
maa...@panic.xx.tudelft.nl
> I read all the advice here and said thanks a several times throughout
> the thread, and stated that I got all the info I could get here. What
> else do you want from me? The crap is over details that certain
> individuals are looking for. Those details are complicated and totally
> off topic.
Problem with looking for advise or information on usenet is that you are
not the person who is in control over what others do to help you. It's
the other way around. If someone has an idea, he or she will try to help
you as good as possible. The more questions you are asked, the better.
It means people are really trying to help. In the end you will have to
evaluate all answers you get yourself. The more answers you reject, the
more dissatisfied you will be with the help you are getting. I myself
have not analysed your problem toroughly (as repair and design is a
hobby and I have more things to do for which my time is paid), but I did
try to give you some hints for other approaches that may work. That is
the kind of information you will get from the usenet. With lots of luck
you will find an out-of-the box solution here, but that is in no way
guaranteed.
Tim Shoppa
> second to make certain occurances "random". If one
> a second, then these occurances would
> follow a predictable pattern. But
> of course that kind of timing is not humanly
> possible with any kind of consistency.
I'm guessing that you're trying to beat some sort of gambling/gaming
system that uses a pseudorandom sequence clocked at 60Hz. A few
off-the-wall comments:
1. You don't have to do it consistently, just enough to put the odds
in your favor. Most games are set by law to returns in the 40-48%
range. Just "hitting the button" in a 1/6 second window (sounds
feasible to me) where you know you've got a 7 or 8 out of 10 chance is
way better. You don't wait for the 1/60th of a second where you know
you win, but instead you wait for a 1/6sec window where there's a
really good chance you'll win.
2. The gaming system's clock is probably nowhere near the 1ppm
accuracy you're stating that you require. It would probably make more
sense to try to phase-lock the "guesser" to the system. This isn't
easy if there's a lot of noise and other pseudo-random uncertainties
involved, but it's not impossible.
If the gaming system is locked to AC power, then there's enough 60Hz
ripple in the light out of a fluorescent or incadescent to lock to that
easily.
I'd be very surprised if a gaming system had a 1/60 second clock, BTW.
Tim.
Rich Grise
> In sci.electronics.repair John Fields <jfi...@austininstruments.com> wrote:
>> Now, what was it you were saying about that 120Hz clock?
>
> I was not presenting it as a complete solution, but as a useful part of
> finding another strategy to solve the problem.
>
> Met vriendelijke groet,
Zaadvragende Ogen! ;-P
With Friendly Greets,
Rich
Rich Grise
DOOOD!!!!! =:-O
He's trying to cheat the slots?!?!??? F-ck, man, I thought he
just wanted to reinvent Bazo's Breaker or something.
Speaking of screwing a casino, I'd rather deal with real feds than
casino security. Like, for example, printing out a scan of a bill,
then trying to use it in a casino changer - you wouldn't even
make it out of the building. (although, I haven't tried to pass one
to a blackjack dealer...) But the little girl at the bank teller window
will happily break it to small bills for you - or actually, the easiest
place to pass bogus bills is at the nudie bar - you flash your bogus
twenty, and ask the babe for change. Then you leave, and go to the next
nudie bar, where you rip off another bimbo $19.00.
It's almost trivial. >;->
(of course, if you're going for hundreds or thousands, then you'll
have to find your own foreign investors. I hear gun-running pays
pretty well, if you like that sort of people.)
Chears!
Rich
maa...@panic.xx.tudelft.nl
> Zaadvragende Ogen! ;-P
Next time, say that to a girl... Or better yet, about a girl behind her
back ;-)
Sear...@mail.con2.com
What?!?
Was that paragraph really necessary?
The problem is the *abuse*. Being called stupid, and troll, or a
bonehead by individuals who couldn't even understand the question, let
alone come up with answers.
Sear...@mail.con2.com
Thanks.
I agree with all that. But what I'm doing has nothing to do with a
gambling system.
Sear...@mail.con2.com
You seem to know quite a bit about this stuff.
Personal experience perhaps? :-)
Sigh...
OK. Here we go.
There are 3 or 4 gamers in the U.S. who have confirmed ability to play
the classic game Ms.Pac-man all the way to the end(133 mazes), while
consuming *all* of the bonus prizes and monsters along the way.
The problem is that our highest scores vary by as much as 100,000
points. So the scores cannot really be a determining factor as far as
who the best in the world is at this game, because we have all
accomplished the same thing. We cannot go further thanks to the game's
end.
Our varying high scores are attributed to the "random" aspects of the
game. There are 252 "random" bonus prizes in a complete game, and these
prizes vary in value from 100 points(Cherry) to 5,000 points(Bananna).
>From what I'm told, the Ms.Pac-man programming code shows that the
register that determines which bonus prizes appear at any given time
incriments 60 times a second. So in 7/60th of a second it will
incriment through all 7 bonus prizes before beginning again. And the
last joystick input before the dot that triggers the prize output is
eaten is responsible for which prize appears. Now if a player could
determine the exact 1/60th of a second a number corresponding to the
5,000 point prize would be the selection *and* had the timing to
activate the correct joystick input at that exact 60th of a second,
that player would be able to make nothing but Banannas appear
throughout the whole game. But of course this is not humanly possible.
So basically the game uses human inconsistency to randomize the prize
output.
There is however an anomaly in the odds. Each of the 7 bonus prizes *do
not* have a 1 in 7 chance of appearing because of the way the
Ms.Pac-man programming code was written.(See below)...
Cherry 0 7 14 21 28
Strawberry 1 8 15 22 29
Orange 2 9 16 23 30
Pretzel 3 10 17 24 31
Apple 4 11 18 25
Pear 5 12 19 26
Banana 6 13 20 27
The register runs through all 32 incriments in just over half a second.
As you can see, all prizes have corresponding numbers. The sequence
goes from 0 to 31, and continually repeats without a pause, skip, or
reset from the time the game is powered on to when it is powered off.
***Unfortunately, the high bonus prizes(Apple, Pear, & Bananna) are
shortchanged in that last line. So as a result the average complete
game score is 874,342.5 points instead of the 905,280 points that it
would be if the odds were in fact 1 in 7 for each prize. The *actual*
odds of getting each prize is shown as fractions and percents here:
Odds of Appearance
******************
Cherry 100 points = 5/32 = 15.625%
Strawberry 200 points = 5/32 = 15.625%
Orange 500 points = 5/32 = 15.625%
Pretzel 700 points = 5/32 = 15.625%
Apple 1,000 points = 4/32 = 12.5%
Pear 2,000 points = 4/32 = 12.5%
Banana 5,000 points = 4/32 = 12.5%
As I mentioned consistently reacting within 1/60th of a second is not
possible, but 1/20th of a second can be achieved with *relative*
consistency, which should be enough to shift the scoring odds ever so
slightly. I say 1/20th because the numbers representing the high value
prizes(Apple, Pear, and Bananna) run through the register within that
amount of time. Determining the exact instant this happens will be
possible through a series of visually references. Since each maze
produces two prizes, and the speeds of game's character movements are
consistent throughout the game. And since we have and can create maze
patterns that run from before the appearance of the first prize to
after the appearance of the second, the exact time the first prize
appears, what it is,and possibly it's travel pattern will make it the
reference for determining what adjustment/s will have to be made before
the second prize appears.
***So the last joystick movement before the dot that triggers the
second prize will be the key.
Since our maze patterns have a lot of pauses, the possibility of
resuming motion at the exact same time a particular second on the
display clicks over is doable with some accuracy above and beyond
rolling the dice.(It's a matter of how many times we can hit this high
speed window over the course of a 5 or 6 hour game).
Even a 25% accuracy of hitting that 1/20th of a second window will add
an average of over 45,000 points to one's scores, with a large
deviation either way.(This is rough math). This would greatly increase
the probability of moving the world record up on the game.
Also, another idea involves aiming for the larger 27/60th of a second
window that the prizes do have an equal chance of occurring, thereby
effectively cutting out the register numbers of 28 to 31. This of
course would be much easier to do, and automatically adds about 31,000
points to one's average score.
As far as drift in the game's hardware timimg, this has already been
considered. But still adjustments can be made by noting the first
specific prize, and then making adjustments for the second prize.
The bottom line is that there will be a lot of human error as far as
timing is concerned, but the player with the *least* amount of errors
should have a higher scoring average over time.
***So it is logical to want to minimize the inconsistency of whatever
timing device is used for reference as much as possible. A second on
the display that doesn't click over accurately within 1/60th of a
second will add it's deviation to that of the human errors which will
already be plentiful. So obviously, the more accuarte the timer is, the
better.
Now that was the dumbed-down explanation of my already twice simplified
project.(I'll have to work my way back to the automatic pattern
generator in the future).
NSM
<Sear...@mail.con2.com> wrote in message
news:1120174978.6...@o13g2000cwo.googlegroups.com...
> Also, another idea involves aiming for the larger 27/60th of a second
> window that the prizes do have an equal chance of occurring, thereby
> effectively cutting out the register numbers of 28 to 31. This of
> course would be much easier to do, and automatically adds about 31,000
> points to one's average score.
What would occur to me first is to replicate the game on a PC and build
whatever timing or scoring you need into the PC software.
N
James Waldby
Sear...@mail.con2.com wrote:
[snip scoring and anomaly stuff and prize %'s]
> patterns that run from before the appearance of the first prize to
> after the appearance of the second, the exact time the first prize
> appears, what it is,and possibly it's travel pattern will make it the
> reference for determining what adjustment/s will have to be made before
> the second prize appears.
>
> ***So the last joystick movement before the dot that triggers the
> second prize will be the key.
>
> Since our maze patterns have a lot of pauses, the possibility of
> resuming motion at the exact same time a particular second on the
> display clicks over is doable with some accuracy above and beyond
> rolling the dice.
...
> As far as drift in the game's hardware timimg, this has already been
> considered. But still adjustments can be made by noting the first
> specific prize, and then making adjustments for the second prize.
...
I didn't see where game hardware timing drift was considered.
Did I overlook something about drift in what you wrote?
Anyhow, this timing problem looks complex enough -- it looks like the
timer may need to slightly speed up or slow down, or to keep track
of scoring and joystick events -- that the best approach would be
a PC- or micro-based timing program. Let PTP="PC timing program".
You want PTP to provide a seconds metronome, to signal the Banana
zone of each second. To make it actually work, I think PTP would
need to know timestamps and values for your joystick inputs and
for scoring. (See * re getting this info.) With that data, PTP
can get syncronized and accomodate for drift. For example,
suppose you do some joystick movement x and then 5 cycles later
the score goes up 500 points; this tells PTP Orange was on the
bonus timer 5/60 seconds ago. After a while PTP can figure out
where Ms.Pac-man is in its 0...31 bonus timer cycle. If, 123
seconds later, Orange is showing up a cycle early relative to PTP,
then PTP increases its per-second delay count by 1 part in 60*123.
PTP should have an adjustable reaction-time offset for different
players. PTP probably should start with a half-minute or so
synchronization phase, and re-sync whenever player tells it to.
* Getting event data: Of course you could set up a board with
several pushbuttons on it and enter data that way, or have an
assistant do so. This might work if you don't have to sync very
often. Also you could attach mercury-switch sensors to wrists
or perhaps to an elastic band that fits on the joystick. For
definitive scoring detection, aim a TV camera at the screen
area where score appears, and decode it in real time. Or if
the game is running on the same computer as PTP, your program
can monitor some bytes of screen memory.
-jiw
Incidentally, regarding the $49 ebay item
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7526393893
(Datum bc620AT ISA time and frequency counter card) that I
mentioned a few days ago, there is a manual for it at
http://www.symmttm.com/pdf/Bus/um_bc620_627at.pdf .
This card looks fairly involved to program, and if you were
to use it I'm not sure whether it would be better to use
the programmable frequency output (pp. 38-39, p. 51) or the
time coincidence strobe (p. 31) or the 1 pps output (p. 11).
Stability is listed as < 2 ms per hour; long term accuracy
can be improved by inputting a 1 pps signal from a GPS unit.
-jiw
Sear...@mail.con2.com
James Waldby wrote:
> [Perhaps drop the newsgroup that isn't sci.electronics.design]
>
> Sear...@mail.con2.com wrote:
> [snip scoring and anomaly stuff and prize %'s]
> > patterns that run from before the appearance of the first prize to
> > after the appearance of the second, the exact time the first prize
> > appears, what it is,and possibly it's travel pattern will make it the
> > reference for determining what adjustment/s will have to be made before
> > the second prize appears.
> >
> > ***So the last joystick movement before the dot that triggers the
> > second prize will be the key.
> >
> > Since our maze patterns have a lot of pauses, the possibility of
> > resuming motion at the exact same time a particular second on the
> > display clicks over is doable with some accuracy above and beyond
> > rolling the dice.
> ...
> > As far as drift in the game's hardware timimg, this has already been
> > considered. But still adjustments can be made by noting the first
> > specific prize, and then making adjustments for the second prize.
> ...
>
> I didn't see where game hardware timing drift was considered.
> Did I overlook something about drift in what you wrote?
Yes you did. Whent you mentioned drift five days ago, I said, "I'm
aware of the consistency of the game hardware. And this project can't
involve tapping into the games clock."
Thanks for the advice but this has to be a "real world" experiment. As
I mentioned it involves going for the world record on Ms.Pac-man, so
the gaming hardware cannot be tapped into to or changed in any way. The
player is the only interface, and info can only be received visually
from the games monitor screen and the the timer's display. This all
comes down to human timing.
BTW Here is some info I uncovered on that acrd you mentioned: "When
DM2000 was first released in 1996, the time synchronization hardware
used was a Datum BC620AT card and time synchronization software from
the Windows NT* Server Resource Kit. The hardware had a potential
problem with the GPS week rollover issue. This time synchronization
software has not been tested by the vendor for year 2000 issues. As a
result of these issues, and because the system was difficult to set up,
we no longer offer this solution."
maa...@panic.xx.tudelft.nl
First, I should admit that my rant may have been a bit harsh. This may
also have been caused by some ignorant people looking for free help on
some illegal stuff (so their questions were very vague and ill defined)
in another newsgroup that I read. I should have only tried to make the
point the input you get is as detailed as the description of the
problem. There was some suspicion your problem being not exactly as you
described, so you would be looking for another solution to solve it in a
proper way. I was just trying to explain the way people react to the
question, I suppose.
Anyway, on topic, I'd like to explain why I stated you should be
sampling at least 120 times a second if you really want to detect
changes that could be occuring 60 times a second. Suppose you take a
sample 60 times a second. Worst case scenario is that a change occurs
immediately after your sample and a next change occurs exactly before
your next sample. You've missed the entire event in that case. The
second-worst case being that a change occurs immediately after your
sample and you record it almost 1/60th of a second after it really
occured.
Rich Grise
> <Sear...@mail.con2.com> wrote in message
>
>> Also, another idea involves aiming for the larger 27/60th of a second
>> window that the prizes do have an equal chance of occurring, thereby
>> effectively cutting out the register numbers of 28 to 31. This of
>> course would be much easier to do, and automatically adds about 31,000
>> points to one's average score.
>
> What would occur to me first is to replicate the game on a PC and build
> whatever timing or scoring you need into the PC software.
Thanks for the judicious snip. :-)
You can get the source code here: http://www.mame.net/
but you have to have a license for the ROMs. I think I have
a de facto license for game ROMs, since I used to repair them
for a living, and the company copied them routinely so the owners/
operators could have spares.
Pac-Man, however, for some reason, is almost impossible to find, unless
you have an actual physical game that you can pull the ROMs from - and if
you have that level of access, just solder a wire onto the nearest clock,
and clock your joystick sniffer in sync, or whenever you want to.
Lessee....
http://www.google.com/search?q=MAME+roms
Have Fun!
Rich
(I also once had to fix an NSM jukebox... ;-) )
Rich Grise
> Thanks for the advice but this has to be a "real world" experiment. As
> I mentioned it involves going for the world record on Ms.Pac-man, so
> the gaming hardware cannot be tapped into to or changed in any way. The
> player is the only interface, and info can only be received visually
> from the games monitor screen and the the timer's display. This all
> comes down to human timing.
Then, if you can't hack the physical game, you'll have to do it the
same way everybody else does:
Practice, practice, practice. ;-)
(Although, somebody could probably come up with a little receiver,
that could sniff clock transitions...)
But if you're intending to cheat in a real-live competition, where
there's the possibility of money exchanging hands, I'd venture to
speculate that most of the regulars of s.e.d would shy away from
such shenanigans. )-;
Good Luck!
Rich
Sear...@mail.con2.com
You know, you speculate, imagine, and assume way too much...
maa...@panic.xx.tudelft.nl
> You know, you speculate, imagine, and assume way too much...
You left room for that ;-) allthough I did enjoy and appreciate your
explanation. Sounds like an interestig project, so good luck!