Phil is fun, his verbal/keyboard skills are somewhat limited when it comes to adjectives, he does needs some lessons in subtlety, wit and sarcasm, and Bill seems to know a lot more than me, as does that Jim dude from Az, and despite significant differences in political philosophy I'm happy to see what any of them has say about technology.
martin
On his chosen subjects he is pretty good, but he does degenerate into snarling rage remarkably quickly, and he remains incensed for remarkably long periods.
-- Bill Sloman, Nijmegen
But I said it first. You have to invent your own abuse if you want to get any brownie points.
And I don't show much sign of blowing a blood vessel.
-- Bill Sloman, Nijmegen
I don't want brownie points, Bill. Brownies are young girls on their way to being Girls Scouts. The first sign of blowing a blood vessel is when it explodes.
-- Service to my country? Been there, Done that, and I\'ve got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida
Kind of like your insane anti America rants, old boy?
-- Service to my country? Been there, Done that, and I\'ve got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida
The Australian scouting movement uses the same name for that particular age-group. The concept has generalised over the years.
True, but the chances of it blowing depend pretty heavily on your blood pressure. Mine is about 130/65.
-- Bill Sloman, Nijmegen
This is "insane" in the Communist Russian sense - if you disagree with my ideology you must be crazy and I have to lock you up in an insane asylum until you see the logic of my position.
Try a little reasoned argument the next time you come across a poltical opinion you don't like. Your education system doesn't exactly prepare you for this sort of discussion, but it is a skill you ought to learn.
-- Bill Sloman, Nijmegen
It is insane for you to sit on the other side of the world and try to influence how I think. Maybe you could learn that, if you tried?
-- Service to my country? Been there, Done that, and I\'ve got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida
That sounded like fun, we have plenty of the cheap skate customer coming through, wanting something for nothing?
Rick 2 to the power of 16 is the maximum counter rate required!
Hi Paul,
Yes, we understand that you're designing the system to detect a maximum of 65536 events per millisecond (Although I'm going to guess that actually your maximum count is 65535, because that's the most a 16-bit counter will give you).
This sub-thread started because John was estimating the accuracy required of the ms timer - the one that says "stop counting and tell me what you've got" - to be sure that the count is accurate to one event. Well, you may not even be interested in 1-event accuracy, but that's the way the conversation turned!
Clearly, the most error you can tolerate on a timer in order to make sure the count is accurate to 1 event is related to the *minimum* time between events. As an example (with made-up numbers, John), if your clock toggles early by 10us and if the PAD happened to detect an extra
2 events in that extra 10us before the clock *should* have toggled, then your count is out by two. The only way to ensure the count is accurate to one event is to make sure that the ms clock transitions at 1ms +/- the smallest possible time-gap between events.John went about it in a different way - , he assumed that the PAD would change its output (at its fastest, when lots of photons are being detected) exactly 65536 times per ms. Obviously if that actually _was_ the case, then the minumum time between events becomes 1ms/65536 and that therefore defines the accuracy of the ms clock neatly in terms of the
1ms period and the 16 bit width of the counter. But unless you can alter the PAD's pulse time plus dead-time so that it's accurately 1/65536 ms, that's not going to happen.The difference between us is that I say "measure or look up the minimum possible time between events and use that number to determine timer accuracy", whereas John says "Assume that the minimum time between events is (conveniently) 1/65536ms and take it from there".
As an aside, somewhere else in the thread, John suggested using the PAD's output to gate a fast clock into the counter. If you do that, you need to make sure that the fast clock is guaranteed to have exactly one edge per event. Failure to do so will result in the PAD gating a clock that's not currently doing anything (missed count) or gating a clock that may transition more than once during the PAD's output pulse (multiple counts per event). However, upon re-reading some of the thread, I realise that John abandoned that idea, so my spiel in my last post about lost/extra counts is redundant.
Anyway, good luck in building your project, Paul - I hope it's a success.
-- Rick
In article , wrote: [....]
I think the OP may have a problem with the car batteries needed to power the ECL version. He is lifting this with a balloon.
BTW: It looks like ECL is going to go away and be replaced by SOI CMOS or something in the next many years.
-- -- kensmith@rahul.net forging knowledge
A rocket, actually. I know he doesn't need ECL - ACT looks to be qute fast enough, though a Xilinx CoolRunner programmalbe logic chip would probably be quicker and save him more space.
So far, I've used 10k ECL, 100k ECl, and ECLinPS. ECL exists to drive transmission lines, whose impedance is always of the order of 50R.
Small voltage swings mean manageable drive currents, and bipolar parts have smaller voltage offsets than MOS parts ....
John Larkin was talking about SiGe parts as being the next step - I imagine he meant something like this
CMOS consumes quite a lot of current when you run it really fast, and ECL doesn't look nearly as bad where you actually need it.
-- Bill Sloman, Nijmegen
Lattice now has ones at even lower power than the CoolRunners. I haven't designed in a CoolRunner since Xilinx killed the 5V parts.
[...]Yes, ECL does well at that.
It could also be SiC or SiN parts that take off next. There's lots of promicing stuff out there.
At high speeds the power is high with CMOS. The nice thing is that you rarely have your whole FPGA or CPLD running at those speeds.
BTW: While we're dreaming about the next generation, I hope it will be able to drive power MOSFETs directly.
-- -- kensmith@rahul.net forging knowledge
If you did think, rather than knee-jerk reacted, it would be a slightly less insane ambition.
Reasoned argument can influence the opinions of reasonable people - if you are dedicated to the idea of being an unreasonable person, programmed to reject all unfamiliar opinions as attempted subversion, then this aproach is clearly futile - but not necessarily insane.
Someone who is that unreasonably suspicious is, of course, insane - the technical term is paranoid.
-- Bill Sloman, Nijmegen
Is that your own diagnosis, or do you have papers from your doctor?
-- Service to my country? Been there, Done that, and I\'ve got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida
Well, I am a doctor, though not one whose opinion would be legally adequate to have you committed to a lunatic asylum. I certainly don't have any papers from my doctor - what would he know about your mental state?
And if you are worried about *my* mental state - because I don't happen to believe in the line of political rubbish that you were educated to accept as right-thinking - you can relax. Over here, and in many of the less red-necked parts of the U.S.A. my political attitudes are not merely acceptable, but also wide-spread, in some areas to the point where political parties based on these attitudes have been elected and have run the relevant countries with reasonable success.
My ideas may strike you as crazy, but you should try and work out why you think they are crazy - and "my primary teacher told me that socialists are communists and communists are bad" is not a persuasive argument..
-- Bill Sloman, Nijmegen
The only person you could have committed is yourself, Bill. Are there still "lunatic asylums" in Europe? That sounds like the right kind of place for your next vacation.
As far as my political and world views, its really none of your damn business. Anyone who doesn't agree 100% with your sick and deluded agenda is "Insane" and they do everything in a "Knee jerk" manor etc...
Its your loss that you don't really understand the United States. You think you do, but its obvious that you've read too many comic books when you should have been cracking your text books. You are a sad old man, and a hopeless loss as far as I'm concerned.
-- Service to my country? Been there, Done that, and I\'ve got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida
Do these USA text books he should be reading give the location of "Knee Jerk Manor" I might want to stay a weekend there ........ :-)
Only joking, I actually clicked on this link to see about FREQ COUNTER help.
Cheers
John
The are psychiatric hospitals in Europe, as there are all over the world, where people can be admitted - sometimes against their will - while the psychiatrists work out a drug regime that will let them function in the community.
As you should be able to work out, I'm not in need of their services.
Would you care to specify which part of my agenda is sick or deluded - ideally with dated citations, which make it easier to deal with "selective" quotations.
I managed to spend enough time cracking the text books to get myself a Ph.D. in chemistry, a couple of patents in electronics and a handful of publications in refereed journals - look for "A.W.Sloman" on
And you also think that I don't really understand the United States - I certainly don't share your blinkered outlook on your country, but then again I don't get most of my information on your country from your pathetic newspapers and your superficial TV news reports.
You would probably do better getting your infomration from comic books
- at least they are free from day to day manipulation.
-- Bill Sloman, Nijmegen
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