>From AA2DU:
>Unfortunately, you cannot use the same IRQ for 2 devices simultaneously
>on an ISA board.
This needs some clarification. Two devices can share IRQ's if one of the
devices is not polling the IRQ in the first place. Case in point: Your
printer ports use IRQ-5 or IRQ-7. But since you are NORMALLY never receiving
data on a printer port, you can use IRQ-5 or IRQ-7 for your serial ports!
This is what I have done with all of my computers and have had no problems.
For the record, I sell computer hardware to computer dealers, and IRQ's are
the least understood animal by so-called computer experts!
Another note: We used to sell generic serial cards (2 ports) that only
supported IRQ-3 and IRQ-4. With some help from the expert in Harvard, MA, I
simply cut the trace on the board that went to IRQ-3 and IRQ-4 and jumpered
them to 5 and 7. It's very easy if you know which ones are which on an AT
bus. You can find that information at any book store.
73
Bill Fisher
>From ki4hn@Cybernetics.NET (Jim Stevens) Fri Apr 8 01:59:57 1994
From: ki4hn@Cybernetics.NET (Jim Stevens) (Jim Stevens)
Subject: IRQ's
Message-ID: <9404080059.AA04424@Cybernetics.NET>
>From KM9P:
>This needs some clarification. Two devices can share IRQ's if one of the
>devices is not polling the IRQ in the first place.
I'll throw my 2 cents worth into the discussion.
Bill, I don't understand what you mean by "Two devices can share IRQ's if
one ... is not polling the IRQ ...". Devices don't poll IRQ lines. Device
drivers might poll devices in which case the device is normally not
considered to be interrupt driven. The whole point of interrupts is so
that the device driver does not tie up the rest of the system by polling
the device.
However, I agree that it is not impossible to share IRQ's between multiple
devices on ISA. It just is more difficult than on EISA or MCA. The reason
for the increased difficulty has to do with the manner in which devices
indicate to the interrupt controller that they have an interrupt. On ISA,
IRQ lines are level driven. The device must raise the IRQ line from a
low voltage to a high voltage and hold it until the interrupt is
acknowledged by the device driver or operating system. While a given
device is holding the IRQ line high, no other device can signal an interrupt
on the same IRQ, so we have a window for missing interrupts. How big the
window is depends on the device driver or operating system. On MCA (and
I believe EISA), interrupts are edge triggered. The interrupt signal is
latched on a falling edge (I think. I don't have MCA specs handy at this
time). Once the interrupt controller has latched the edge another device
could generate an interrupt on the same IRQ.
Now putting on my armor and ducking.
73, Jim Stevens (device driver writer by trade), KI4HN
ki4hn@cybernetics.net
>From H. Ward Silver" <hwardsil@seattleu.edu Fri Apr 8 03:55:37 1994
From: H. Ward Silver" <hwardsil@seattleu.edu (H. Ward Silver)
Subject: Rating System Announcement
Message-ID: <Pine.3.07.9404071937.D8658-e100000@bach>
As if we didn't have enough to yak about...but since the K-index is
running about four or five, this reflector is about all that's open!
To the CQ-Contest Internet Reflector
After watching a lot of thoughtful discussion go by on the
reflector regarding issues such as single-multi, geographic
advantages, regional reporting, scoring, etc. I am pleased to release
this introduction to our operator rating system. The time appears to
be right for the subject and I know we'll receive a lot of comments in
reply.
I know you'll want the specifics of how it all operates, and that
will be forthcoming. But first, I want to present a simple
introduction that outlines the broad concepts for some public review
and comment.
To give credit where credit is due, Adam, AA7FT, first proposed
the idea of the Class-based system following the 1990 World Radiosport
Team Championships. What has grown from that initial idea is the
result of a lot of considered review and suggestions from all of the
rating system authors who have all contributed good ideas.
Thanks in advance for your time in review and discussion. If you
have specific review comments, please reply to the coordinating
author's email address below. I'll summarize them for both the rating
system author's group and the reflector. I would expect that general
comments are welcome on the reflector, however, at the sysop's
pleasure, of course.
I will be attending Visalia with more details of the system
expecting to hear from many of you firsthand. It should be a busy
weekend!
For the authors group, 73
H. Ward Silver, N0AX
--- cut here ---
Contest Operator Rating System - Introduction
Coordinating Author: H. Ward Silver, N0AX <hwardsil@seattleu.edu>
22916 107th Ave SW
Vashon, WA 98070
Contributing Authors:
Jack, WA0RJY <oolon@eskimo.com>
Adam, AA7FT <4146960@mcimail.com>
Eric, K3NA <ERIC.L.SCACE@sprintintl.sprint.com>
Dave, K8JLF <hoaglin@husc15.harvard.edu>
Rick, K7GM <aoniswan@ecuvm.cis.ecu.edu>
Alan, K6XO <alan@dsd.es.com>
Lou, K1YR <amity2@yalevm.ycc.yale.edu>
Rick, N6XI <tavan@tss.com>
Randy, K5ZD <K5ZD@world.std.com>
The following introduction is intended to introduce the broad
concepts of the proposed system to the contest community. The
specific mechanics of the system are available in a detailed document
that is available from N0AX by email on request. These details have
intentionally been left out of this general document to avoid
"information overload". The system has been through four levels of
draft review and will continue to be revised and the calculations
tested on actual contest data before proposing a public
implementation.
Background & Introduction
As the popularity of contesting has grown worldwide, it has been
conclusively demonstrated that the rules for most contests result in
certain geographic and population-related advantages. Informal
discussions over many contest seasons have evaluated rule changes to
"level the playing field" --without success. Because contesting is a
worldwide activity, it has become increasingly apparent that ANY given
set of rules will produce structural inequities among otherwise equal
competitors.
Their highly competitive spirit naturally leads contesters to want
to have a "universal" set of metrics by which they might measure their
performance in an absolute way. Although this remains an elusive
goal, we have devised an operator rating system that allows the
individual operator to identify and compete against his or her peers,
equal against equal. Though doubtless imperfect, the system addresses
geographic and population factors.
We expect that this system will evolve to accommodate new forms of
contesting and necessary structural adjustments. However, like the
batting average in baseball and rankings in chess, an operator rating
system, if adequately considered at its inception and administered in
an unbiased and open manner, should provide a solid basis for growth
of contesters and the sport of contesting.
Briefly, the proposed system sets up three performance classes of
operators and assesses an operator relative to others in the same
performance class and the same geographic region. The measure of
performance is a numerical Rating that combines both class and
relative performance within the class.
The three classes -- "Competitor", "Expert", and "Master" --
formalize relative distinctions that have long been familiar in the
contesting community.
The specific definitions of a region depends on the contest. A
feature of the system expands an operator's initial region to include
a minimum number of peers.
After each contest, an operator's Rating may be updated, on the
basis of the operator's score and the scores of others in that class.
If the operator performs well enough for long enough, he or she
advances to the next higher class and the Rating is recalculated
relative to the new class. Note that the Rating changes are based
SOLELY on performance relative to other scores in the operator's
class.
An operator may submit scores from different locations, because
the performance in each contest is judged according to the region of
the score. Similarly, an operator may participate in multioperator
teams or guest-operate at different stations.
The Rating becomes a yardstick measuring both coarse (class) and
fine performance of an operator. The system establishes a broad peer
group for an operator while also giving him or her a measure of
relative performance within that group.
An operator's Rating follows him or her throughout their careers
without regard to where the operations have taken place. There is no
need to change either the rules, scoring, or categories of any
contest. Similarly, there is no need to attempt to assess the
potential performance of a station in order to qualify or handicap a
particular score. By measuring a score against others in the same
class and region, the system largely neutralizes structural and
geographic inequities.
At this point, the active contester will be asking, "What's in it
for me?" and "Is it fair?". To address the first, the intense
discussions on geographic advantage over the years are a good example
of why an operator-based system will be useful. As solar activity
hits the bottom of the cycle, the ability to compare one's own
performance against representative peers becomes ever more important.
This is also true for consideration of contest categories and scoring.
For the Big Guns, this system does away with the perceived need
for score equalization or handicapping. The significant achievements
of these standard-setting men and women will finally have a stable
framework for recognition. In addition, ratings may be developed from
historical data, allowing comparisons to operators of the past.
The Medium Gun operators are provided with a measurement of
performance that charts their progress toward the top level of the
sport. They are compared to others of similar ability, allowing a
clearer view of their relative capabilities. The achievement of top-
quality performance is clearly rewarded and duly noted.
Little Guns everywhere will benefit from such a system as this by
being compared to each other instead of being left perpetually in the
dust of the experienced competitors. New entrants can have their
modest accomplishments rewarded and receive valuable and timely
feedback. The discouragement of fighting up from the bottom of the
published listings can be lessened by a more appropriate standard of
evaluation.
If encouraging activity amongst the newcomers and up-and-comers is
but one result of a peer-group rating system, then our sport is the
true winner.
As to the second question, we do not pretend that any proposed
system will be perfectly accommodating of all possible circumstances.
In the first paragraph of this introduction, we acknowledge that any
set of rules imposes some arbitrary constraints. However, if the
system is "reasonable" and "consistent", then it may be considered
"fair". It is our hope that during the review and testing process
significant flaws will be addressed. The methods proposed will remain
understandable and open to the contesting public.
The detailed system description will discuss how to calculate the
Rating, how it changes with each new score, and where the scores come
from. We believe that this detailed, concrete proposal addresses the
basic underlying need for operator peer comparison, without requiring
changes in any contest rules, handicapping, station assessment, or
score equalization. We welcome vigorous discussion. Send your
written comments or requests for a draft copy of the detailed system
proposal to us at the following addresses:
H. Ward Silver, N0AX - callbook address
Internet - hwardsil@seattleu.edu
Packet - N0AX@N7DUO.WWA.USA.NA
>From Don Nutt KJ6TC <kj6tc@netcom.com> Fri Apr 8 08:22:36 1994
From: Don Nutt KJ6TC <kj6tc@netcom.com> (Don Nutt KJ6TC)
Subject: More IRQ's
Message-ID: <Pine.3.85.9404080036.A23698-0100000@netcom4>
Well as has been stated if more than 1 device is active on the same IRQ,
problems can and most likely occur. My solution was to hack and old 16
bit controller board for the smaller of the two card edges. Using a
decent reference guide (any manual, photo copied pages will do) identify
the locations for IRQ 10, 11, 12, 13, 14, and 15. Note, for those not
aware, IRQ 9 will get you in trouble. It is cascaded with IRQ 2 (the link
from the first interrupt controller to the second).
Now you can't use 13 and 14. Thats the co-processor and the hard drive
IRQ's respectively. Now look you have 10, 11, 12, 15 which are referred
to as reserved. Reserved for what? Anything that can access them.
I personally use IRQ's 11 and 12. I have been looking at 15 in recent
days. Oh and yes CT works great. Try it some time.
For those of you who value your 386, 486, or P5, a new entry in the under
$100 catagory is a 2 port serial card from Sealevel Systems Inc. The
board features,
2 Serial ports (DB-9)
Interrupt and address selectable (2-5,10,11,12 & 15)
16550's Standard
(803) 843-4343
All for $89.00.
I have not tried or tested the boards and know of no one within my group
who currently have one, however we are going to order and check one out.
Don Nutt
kj6tc@netcom.com
>From Earl Morse <E.Morse@mi04q.zds.com> Fri Apr 8 15:44:08 1994
From: Earl Morse <E.Morse@mi04q.zds.com> (Earl Morse)
Subject: Contest Clubs in Houston area
Message-ID: <9404080944.A23565@mi04q.zds.com>
Looks like I'm moving to Houston, TX.
Any information on contest clubs, people, or activities in that area
would be appreciated.
Earl Morse
KZ8E
e.morse@zds.com
>From Peter G. Smith" <n4zr@netcom.com Fri Apr 8 12:57:05 1994
From: Peter G. Smith" <n4zr@netcom.com (Peter G. Smith)
Subject: More IRQ's
Message-ID: <Pine.3.85.9404080405.A328-0100000@netcom6>
Maybe I'm missing something, but I got a Boca card with two additional
serial, one parallel and one game port for $15. True, it doesn't have
selectable IRQs but there has already been sufficient discussion here
about how to handle that. Got it from MEI/Micro Center.x
73, Pete
n4zr@netcom.com
NOTE: New Address
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