<How can I format a rd54 disk on a rt11 5.3 ?
You cannot unless you write your own utility.
<(disk & floppy are on RQDX3 controller)
You need the XXDP diag for that.
<.FORMAT DU0:
<
<i get "device not supported, ...)
I sounds like the Viking series. Zane was kind enough to post a few things
I scanned which includes an OCR of the Viking manuals along with a few gif
scans of pages that the OCR did not keep lined up.
Feel free to contact me off list for more info.
ftp://zane.brouhaha.com/pub/dan/viking_scsi
>I have a SCSI card I was given and I'd like to find data or info
>to use them. There is no question they are SCSI from the chips and
>connectors.
>
>The boards appear to be MTI QTS25 (viking marked on one Eprom). Standard
>dual height dual width.
>
>I'm hoping they are MSCP as I play to try them.
Depends on the PAL that is installed. The markings are as follows:
QTO= Tape only (TMSCP)
QDO= Disk only (MSCP)
QDT= Disk and Tape.
Dan
---Original Message-----
From: CLASSICCMP(a)trailing-edge.com <CLASSICCMP(a)trailing-edge.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Friday, June 04, 1999 4:01 PM
Subject: RE: Formatting disk on rt11
>Alternatively, if you have a VS2000, it has a RQDX3-compabitle
> formatter built into it.
I just formatted the disk in a MVII with the diagnostic tape.
>What error message do you get when you try DIR DU0: ? If it's a
>"?DIR-F-Error reading directory",
I still get this one ...
>then you probably only need to INIT DU0:
>to make it usable.
.INIT Du0:
DU0: Initialize are you sure ?Y
?DUP-F-Size function failed
thanks,
emanuel
>Hi all,
>
>How can I format a rd54 disk on a rt11 5.3 ?
>
>(disk & floppy are on RQDX3 controller)
>
>Doing something like
>
>.FORMAT DU0:
>
>i get "device not supported, ...)
You need the ZRQC?? formatter on bootable XXDP+ media for your machine.
Do you have a RX50 floppy? RX33 floppy? TK50? RL02? RX02? I can
get you the formatter on just about any media... (it *should* have shipped
with your machine in the first place, but someone may have misplaced
the disks at least once in the past decade or so.)
Alternatively, if you have a VS2000, it has a RQDX3-compabitle formatter
built into it.
>P.S. Booting from DU1: works, so the controller & driver should be OK.
>Trying accesses to DU0: I see the LED of the disk drive on.
What error message do you get when you try DIR DU0: ? If it's a
"?DIR-F-Error reading directory", or a "?DIR-F-Input error", then you probably
do need to low-level-format the drive. If you get a
"?DIR-F-Invalid directory", then you probably only need to INIT DU0:
to make it usable.
--
Tim Shoppa Email: shoppa(a)trailing-edge.com
Trailing Edge Technology WWW: http://www.trailing-edge.com/
7328 Bradley Blvd Voice: 301-767-5917
Bethesda, MD, USA 20817 Fax: 301-767-5927
Lawrence LeMay wrote:
>> What should I do? Am I ever likely to find a use for them if I take
them?
>>
>
>Hmm, If they are DSDD and in an external case, i would like to have one
>of those. Woudl you be willing to get one and ship it? I assume it
>would be relatively easy to ship since you say the original packaging
>is available.
>
Sorry, no external cases and I don't know what they are. These are specific
to 220v 50hz.
I thought S100 style machines had drives with 12v connectors.
>How can I format a rd54 disk on a rt11 5.3 ?
You can't.
>(disk & floppy are on RQDX3 controller)
>
>Doing something like
>
>.FORMAT DU0:
>
>i get "device not supported, ...)
Yep, because the FORMAT code doesn't truly know how to format an RD
series disk. The disks are formattable, but you must use the XXDP
diagnostic ZRQC??
>P.S. Booting from DU1: works, so the controller & driver should be OK.
>Trying accesses to DU0: I see the LED of the disk drive on.
The drive can obviously be referenced, but won't be usable until you
have it formatted.
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com |
| Unix Support Engineering Group | (home): mbg!world.std.com |
| Compaq Computer Corporation | addresses need '@' in place of '!' |
| 110 Spitbrook Rd. ZK03-2/T43 | URL: http://world.std.com/~mbg/ |
| Nashua, NH 03062 | "pdp-11 programmer - some assembler |
| (603) 884 1055 | required." - mbg |
+--------------------------------+-------------------------------------+
>...This could get confusing eh - two Kevins.
>
I guess I have fully demonstrated just how confused I was/am. I have
just, once again, broadcast a private reply.
Here I sit day after day saying "that was a silly message to broadcast,
why did so-n-so waste my time by posting it? it should have been a
private message, blah, blah, blah,..." and so I go and do the same thing.
My apologies, but, oh what the heck...would so-n-so please use
better judgement deciding what should be broadcast and what should
be private messages. Thank you
----------------------------------------------------------------------------
-------------------------------
Kevin Stumpf * Unusual systems * www.unusual.on.ca
+1.519.744.2900 * EST/EDT GMT - 5
Collector - Commercial Mainframes & Minicomputers from
the 50s, 60s, & 70s and control panels and consoles.
Author & Publisher - A Guide to Collecting Computers &
Computer Collectibles * ISBN 0-9684244-0-6
.
Hi all,
How can I format a rd54 disk on a rt11 5.3 ?
(disk & floppy are on RQDX3 controller)
Doing something like
.FORMAT DU0:
i get "device not supported, ...)
Any help ?
thanks,
emanuel
P.S. Booting from DU1: works, so the controller & driver should be OK.
Trying accesses to DU0: I see the LED of the disk drive on.
"Fred Cisin (XenoSoft)" <cisin(a)xenosoft.com> wrote:
> Any good sources for routine and/or user information about the Horizon?
> f'rinstance: what's the pinout on those 15 pin D "parallel" connectors?
> Any chance the signals are close enough to be cabled into a centronics
> style port? I haven't applied power to it yet; anything exceptional to
> watch out for?
Yeah. Fire.
I'm only half joking: Stan Sieler and I have had about the same
experience, which is that one of the tantalum caps near a voltage
regulator (connected between +mumble and ground on the input leg of
the regulator) turns into a noise, fire, and magic soot emitting
diode on first application of power to the card(s). As near as I can
tell, the cap shorts to protect the regulator from voltage, but I'm
a software weenie with a soldering iron so what do I know?
So leave the cover off after you re-insert the cards (you're going to
pull them to check the power supply voltages, right?), for that matter
make sure you leave some space between the cards when you put them
back in, and be ready to hit the switch.
ObTony: this problem is amenable to component-level repair. Clean the
soot off and replace the capacitor.
-Frank McConnell
This could get confusing eh - two Kevins.
How long have you been on the CCL? I'm delighted to know another
collector in Kitchener. That's wonderful. That makes 3 who will admit it.
Why don't you come to my "ware"house and see it. How about tomorrow
at either 10am or 1:30pm. It is easy to get to being near the corner of
King and Victoria.
Yours in good faith.
----------------------------------------------------------------------------
-------------------------------
Kevin Stumpf * Unusual systems * www.unusual.on.ca
+1.519.744.2900 * EST/EDT GMT - 5
Collector - Commercial Mainframes & Minicomputers from
the 50s, 60s, & 70s and control panels and consoles.
Author & Publisher - A Guide to Collecting Computers &
Computer Collectibles * ISBN 0-9684244-0-6
.
Hi,
Does anyone know what all the numbers on the backs of Intel Magnetics
bubble memory modules mean?
One of the three modules that I have has a penciled-in line separating
every 4th digit, so it looks like maybe some kind of address, but I
think the modules each store 128KB and 16 bits wouldn't be enough.
Besides that, I can't think of any use for address listings on the
modules.
e.g.:
09FHJ 8333 (<-- probably a date code)
FFF7BAFBFFFBFEBF
7BB3FFFBFEFBFBFE
FBFF7BF3DDBFDFBF
BFFFFFFDFDFFFFFF
DFFDFFFFFFBFFDFF
--
Doug Spence
ds_spenc(a)alcor.concordia.ca
http://alcor.concordia.ca/~ds_spenc/
With the aid of a dedicated processor, this job is easy. Since the work is
already done, I can send you a zip file of the details and the required
code.
Dick
-----Original Message-----
From: John Ott <jott(a)mastif.ee.nd.edu>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Friday, June 04, 1999 11:23 AM
Subject: Re: at style keyboards and mc68000
>Hello -
>
>I would be interested in seeing this.
>
>john
>
>>
>> Hi,
>>
>> ----------
>> > From: Tony Duell <ard(a)p850ug1.demon.co.uk>
>> > To: Discussion re-collecting of classic computers
>> <classiccmp(a)u.washington.edu>
>> > Subject: Re: homemade computer for fun and experience...
>> > Date: Sunday, April 04, 1999 10:49 AM
>>
>> > True. But AFAIK the AT keyboard host interface was never implemented in
>> > TTL (it always used a programmed 8042 microcontroller), so it's a
little
>> > harder to build from scratch.
>>
>> We used on our mc68000 boards a 68681 DUART & and some inverters as a
>> keyboard interface for xt/at. Was very simple. If anybody needs it, i
could
>> dig it out again.
>>
>> cheers,
>> emanuel
>>
>
>
>--
>
>***********************************************************************
>* John Ott * Email: jott(a)saturn.ee.nd.edu *
>* Dept. Electrical Engineering * *
>* 275 Fitzpatrick Hall * *
>* University of Notre Dame * Phone: (219) 631-7752 *
>* Notre Dame, IN 46556 USA * *
>***********************************************************************
>
Hi,
----------
> From: Tony Duell <ard(a)p850ug1.demon.co.uk>
> To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
> Subject: Re: homemade computer for fun and experience...
> Date: Sunday, April 04, 1999 10:49 AM
> True. But AFAIK the AT keyboard host interface was never implemented in
> TTL (it always used a programmed 8042 microcontroller), so it's a little
> harder to build from scratch.
We used on our mc68000 boards a 68681 DUART & and some inverters as a
keyboard interface for xt/at. Was very simple. If anybody needs it, i could
dig it out again.
cheers,
emanuel
<I used 5/8" plywood and 2x4 all around mounted vertically for extra
<support for the shelves. I would not use anything less. Try sticking a
<couple S-100 chassis on a shelf of 1/2" plywood or supported with less
Err... I've done it and 1x2 and 1/2" play do it real well and I do have a
few s100 crates.
<than a 2x4 and unless you have additional support in the way of diagonal
<cross-members or extra support underneath the shelf it'll bow or break.
<Maybe not right away, but with time it'll start to sag.
the trick is you box the underside of the shelf in 1x2 and put one down the
middle for support. then that assembley is screwed to a 2x4 at the corner
and a pair of diagonal braces on the back of 1x2 and side if needed. Use
wallboard screws to assemble rather than nails, they hold better.
<It saves much time to use steel brackets instead of cutting slots into the
<wood. I did my first shelf with the latter design and it took a long
What slots? It can be sone that way but it's not a required thing.
<If I had to do it over I'd buy pre-fab shelves like the Gorilla racks.
They are nice and all but the wood can be cheaper especially if you can
scrounge. Also wood can be configured for odd sizes like a 27" wide
space between the h960 and the window. ;)
Allison
Today I visited an NC machining establishment that is to close down soon.
There is an operating PDP11/23 there that I have my eye on.
Amongst the other accumulated stuff were 8 X Memorex 8" floppy drives, never
used and still in their original packaging. There were 2 models, 550 and
651. They are about 4" high and powered by 220v, 50Hz. The model 550's have
an edge connector while the 651's have a rectangular multi-pin connector.
The delivery documentation is dated in May 1977 and also listed
documentation and software that wasn't in the box I opened and is probably
missing. They were never used because they were bought in error.
What should I do? Am I ever likely to find a use for them if I take them?
Hans Olminkhof
Please ponder this question.
We either collect mainframes, minicomputers, or microcomputers. In the mix
there is hardware, software, documentation, spares, and related material
such as magazines, books, novelties. There might also be the original
boxes.
What percentage of your space is taken up by the hardware and how much
by everything else? What is the ratio of actual computers to all the other
stuff that goes along with them? Please tell me the catagory(s) of computer(s)
you collect (mainframe, etc.), and what your percentages are.
I am working on an article and also on the 2nd edition of A Guide, so your
estimates would be very helpful.
Thank you very much.
----------------------------------------------------------------------------
-------------------------------
Kevin Stumpf * Unusual systems * www.unusual.on.ca
+1.519.744.2900 * EST/EDT GMT - 5
Collector - Commercial Mainframes & Minicomputers from
the 50s, 60s, & 70s and control panels and consoles.
Author & Publisher - A Guide to Collecting Computers &
Computer Collectibles * ISBN 0-9684244-0-6
.
I would be very interested in the 11/34 rack with the two RK05's, and the
ASR33.
I have no interest in the 11/84, and while I am somewhat interested in the
8i, I already have an 8E so I should take a back seat to anyone who doesn't
have an 8.
I'm in Missouri, so Iowa wouldn't be that big of a deal for me. I would be
willing to tandem up with others and take a hand in getting the equipment
and splitting it up with other collectors. If anyone wants to get together
on this, just let me know.
I certainly meet criteria 1 through 3, and 4 as well if someone will partner
up with me for the drive and dissemination.
Jay West
-----Original Message-----
From: Ethan Dicks <ethan_dicks(a)yahoo.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Friday, June 04, 1999 7:09 AM
Subject: Re: Are you sitting down?
>--- Anthony Clifton - Wirehead <wirehead(a)retrocomputing.com> wrote:
>>
>>
>> I have in my garage:
>>
>> (1) PDP-11/34 with RK05j and RK05f
>> (1) PDP-11/84 with RA80 and TU80
>> (3) PDP-8/I, one with high speed paper tape punch reader and
>> one with DECTape
>> (1) ASR-33 which goes with the 8/Is
>
>Nice set.
>
>> I would like these machines to leave my garage, preferably all
>> at the same time, and travel to someone else's place who has:
>>
>> 1. Enough space to give them a permanent home
>> 2. Enough time to restore and preserve them as they SHOULD BE
>> 3. Enough love for them to not turn them into some kind of weird
>> investment scheme for EBay
>> 4. ...and Enough money to bring an appropriately sized vehicle
>> with a lift gate to Des Moines, Iowa to retrieve them
>
>I suspect that many people on the list have number one, quite a few have
number
>two, a good many of us have number three, but number four is the kicker.
>
>I'm in Ohio and I'm not prepared to haul 4+ racks from Iowa (plus I already
>have an 8/i and some of the other stuff)
>
>> At any rate, I intend to only sell these to someone on ClassicCmp.
>> They will NOT appear on Ebay, Usenet or any other forum frequented
>> by people who are not necessarily collectors.
>
>Good for you.
>
>> The 8/Is are 3 out of a set of just under 4000 ever produced.
>
>Wow. I haven't looked up the numbers in Doug Jones' FAQ lately; I thought
>there were more of them made than that.
>
>> I'd like ideas, suggestions, etc. If anyone REALLY, REALLY wants these
>> and just know you have to have them, and you have the above
characteristics
>> and you have money, trades, etc. I'm willing to consider that too.
>
>Of all the systems you've mentioned, the -8/i with the DECtape is the only
>part that I would really want, partially because my only DECtape is a
>TU56/TD8E combo, and because I have always wanted to run OS/8 on my own
>-8/i, but I have no mass storage device for it (only high-speed paper tape)
>
>You are over 10 hours drive from my house, and I'm a lot closer than most
of
>the people on the list. It's a worthy goal, but to make a road trip from,
>say, California, would be an epic journey. If anyone from the East Coast
>is willing to make the trip, I could be interested in participating in the
>western leg of it.
>
>-ethan
>
>_________________________________________________________
>Do You Yahoo!?
>Get your free @yahoo.com address at http://mail.yahoo.com
>
>
--- Anthony Clifton - Wirehead <wirehead(a)retrocomputing.com> wrote:
>
>
> I have in my garage:
>
> (1) PDP-11/34 with RK05j and RK05f
> (1) PDP-11/84 with RA80 and TU80
> (3) PDP-8/I, one with high speed paper tape punch reader and
> one with DECTape
> (1) ASR-33 which goes with the 8/Is
Nice set.
> I would like these machines to leave my garage, preferably all
> at the same time, and travel to someone else's place who has:
>
> 1. Enough space to give them a permanent home
> 2. Enough time to restore and preserve them as they SHOULD BE
> 3. Enough love for them to not turn them into some kind of weird
> investment scheme for EBay
> 4. ...and Enough money to bring an appropriately sized vehicle
> with a lift gate to Des Moines, Iowa to retrieve them
I suspect that many people on the list have number one, quite a few have number
two, a good many of us have number three, but number four is the kicker.
I'm in Ohio and I'm not prepared to haul 4+ racks from Iowa (plus I already
have an 8/i and some of the other stuff)
> At any rate, I intend to only sell these to someone on ClassicCmp.
> They will NOT appear on Ebay, Usenet or any other forum frequented
> by people who are not necessarily collectors.
Good for you.
> The 8/Is are 3 out of a set of just under 4000 ever produced.
Wow. I haven't looked up the numbers in Doug Jones' FAQ lately; I thought
there were more of them made than that.
> I'd like ideas, suggestions, etc. If anyone REALLY, REALLY wants these
> and just know you have to have them, and you have the above characteristics
> and you have money, trades, etc. I'm willing to consider that too.
Of all the systems you've mentioned, the -8/i with the DECtape is the only
part that I would really want, partially because my only DECtape is a
TU56/TD8E combo, and because I have always wanted to run OS/8 on my own
-8/i, but I have no mass storage device for it (only high-speed paper tape)
You are over 10 hours drive from my house, and I'm a lot closer than most of
the people on the list. It's a worthy goal, but to make a road trip from,
say, California, would be an epic journey. If anyone from the East Coast
is willing to make the trip, I could be interested in participating in the
western leg of it.
-ethan
_________________________________________________________
Do You Yahoo!?
Get your free @yahoo.com address at http://mail.yahoo.com
At 07:41 AM 6/3/99 -0400, you wrote:
>Please ponder this question.
>
>We either collect mainframes, minicomputers, or microcomputers. In the mix
>there is hardware, software, documentation, spares, and related material
>such as magazines, books, novelties. There might also be the original
>boxes.
>
>What percentage of your space is taken up by the hardware and how much
>by everything else? What is the ratio of actual computers to all the other
>stuff that goes along with them? Please tell me the catagory(s) of
>computer(s)
>you collect (mainframe, etc.), and what your percentages are.
>
>I am working on an article and also on the 2nd edition of A Guide, so your
>estimates would be very helpful.
>
>Thank you very much.
>----------------------------------------------------------------------------
>-------------------------------
>Kevin Stumpf * Unusual systems * www.unusual.on.ca
>+1.519.744.2900 * EST/EDT GMT - 5
>
>Collector - Commercial Mainframes & Minicomputers from
> the 50s, 60s, & 70s and control panels and consoles.
>
>Author & Publisher - A Guide to Collecting Computers &
>Computer Collectibles * ISBN 0-9684244-0-6
>.
>
I collect home Micros and live in a 1BR apartment. Most of my computer
apparatus is in my BR but there is some overflow into the LR like my TRS-80
M2, 3 of the huge HDDs, and peripherals and disks, and where I also have
other non-comp. electronic equipment. Fortunately I have 12' ceilings.
Docs and disks take up around 50 sq.ft.x 10" on shelves and in a filing
cabinet.
Monitors and terminals take up about 42 sq.ft.x 1' on top of my
full-length former dresser.
A row of creatively stacked desktops and printers is around 48 sq ft in
front of that.
Racks and cabinets with computers, peripherals, parts and test equipment
take up another 50 sq.ft.x18"
Workbench and primary computers and equipment occupy about 30 sq.ft.x3'
under the shelving.
Wasting no storage potential, the space under my bed is also occupied, mainly
by periperals. Another 24 sq.ft. You do the mathematics. xxx cu. ft.
Do I wish I had a garage ? Hell yes !!
But a museum-workspace would be much better, even if it meant grubby budding
JDs got to mistreat them.
ciao larry
lwalker(a)interlog.com
Let us know of your upcoming computer events for our Events Page.
t3c(a)xoommail.com
Collectors List and info http://members.xoom.com/T3C
On or about 09:21 PM 6/3/99 -0700, Sellam Ismail was caught in a dark alley
speaking these words:
[snip]
>This is still insane. Visit www.tucows.com and download the programs that
>Windows should have come with in the first place, instead of the
>brain-dead schlock you get with a stock install.
I've only used the "schlock" when absolutely necessary; i.e. at a friend's
house w/o an Internet connection to download something better and that's
all he has. Nonetheless, IIRC the original question was "how do I get this
shit to work," not "what works better than this shit." With that in mind, I
hope my original suggestions were helpful.
>Or, if you want, I can send you a copy of ProcommPlus for DOS that works
>under Windows. Its my old trusty friend. Easy to use, easy to configure,
>solid.
I've not worked with ProcommPlus for DOS, but IMHO the Windows-based
version was less than ideal. [that's diplomatic speak for "it really sucks."]
For a windows based solution, I've had excellent luck with NetTerm.
*Everything* is configurable, it's very small, extremely fast, has a
built-in FTP Daemon (tho that's a bit tricky to set up -- it takes some
playing to get it right & secure) and works not only with direct comm
lines, modems & the like, but also works with the Internet for telnetting
as well. For me, it's an all-around solution.
Or, like you failed to quote in my original message,
--------
Or, do as I do: grab your trusty Tandy 200 with the attitude of "Screw
WinBlows - this works better!"
--------
As always, YMMV, but my mileage is great!!! ;-)
Roger "Merch" Merchberger
=====
Roger "Merch" Merchberger -- zmerch(a)30below.com
SysAdmin - Iceberg Computers
===== Merch's Wild Wisdom of the Moment: =====
Sometimes you know, you just don't know sometimes, you know?
Ok, I asked my resident family lawyer a few questions concerning the
recent computer privacy debate and here's what he had to say:
I asked:
Say you buy someone's old computer from them and it contains their
personal data that they forgot to delete. Say its really personal stuff
(love letters, sexual fantasies, journals, etc).
A) do you "own" that data?
B) are you free to do with it as you please?
C) can the original owner sue you for anything if you publish that data
(like sell it to the National Enquirer?)
And his replies:
A) do you "own" that data?
It goes to the intention of the parties. I don't think that the seller
intends to sell private information only the computer.
B) Are you free to do with it as you please?
No, you would be liable for any invasion of privacy.
C) can the original owner sue you for anything if you publish that data
(like sell it to the National Enquirer?)
Yes.
--
Sorry if these questions were rather simplistic. If anyone has some
better questions to ask then send them to me and I'll forward them along.
Sellam Alternate e-mail: dastar(a)siconic.com
------------------------------------------------------------------------------
Don't rub the lamp if you don't want the genie to come out.
Coming this October 2-3: Vintage Computer Festival 3.0!
See http://www.vintage.org/vcf for details!
[Last web site update: 05/25/99]
hello,
if i use scanrite to scan a hardisk with bad sectors, will the bad
sectors remain or get repaired? With some other programs, everytime i
scan the number of bad sectors get doubled...
please reply to me
shoeb
I don't think there's much risk of that. Besides, they have to email me to
know where to send the $$$. I doubt this occurred to you, eh, Sam?
-----Original Message-----
From: Sellam Ismail <dastar(a)ncal.verio.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Thursday, June 03, 1999 9:44 PM
Subject: Re: Northstar Horizon
>On Wed, 2 Jun 1999, Richard Erlacher wrote:
>
>> This isn't exactly what you're discussing, but . . . I've got, in my hand
an
>> S-100 board, not fully populated, silkscreened
>>
>> "North Star Computers, Inc.
>> Z-80A Processor Board Z80-A2"
>>
>> I'll send this jewel via USPS Priority mail, as is, to the first person
>> whose $3.20 I get in the mail to cover mailing.
>
>That doesn't make sense. What if 20 people take the time to send in
>$3.20? Sure, I know how you always gripe about people who say they want
>something and then don't follow through, but this solution is not good.
>
>Sellam Alternate e-mail:
dastar(a)siconic.com
>---------------------------------------------------------------------------
---
>Don't rub the lamp if you don't want the genie to come out.
>
> Coming this October 2-3: Vintage Computer Festival 3.0!
> See http://www.vintage.org/vcf for details!
> [Last web site update: 05/25/99]
>
Rumor has it that Fred Cisin (XenoSoft) may have mentioned these words:
>But how do I lobotomize that silly "HYPER-TERMINAL" app in Windoze95 to
>convince it that I do NOT want it to dial, wait for carriertone, etc.?
I've found the best way to force HyperTerminal to do this is tell it to
dial a stupid number like "876" and when it starts out to dial, just click
cancel. it knocks you back to the terminal screen, but leaves the
connection to the com port open.
Or, do as I do: grab your trusty Tandy 200 with the attitude of "Screw
WinBlows - this works better!"
Hope this helps,
Roger "Merch" Merchberger
--
Roger "Merch" Merchberger --- sysadmin, Iceberg Computers
Recycling is good, right??? Ok, so I'll recycle an old .sig.
If at first you don't succeed, nuclear warhead
disarmament should *not* be your first career choice.
I am selling an 11/45 out of the rack for US$150.
Please contact me for details if you are interested.
----------------------------------------------------------------------------
-------------------------------
Kevin Stumpf * Unusual systems * www.unusual.on.ca
+1.519.744.2900 * EST/EDT GMT - 5
Collector - Commercial Mainframes & Minicomputers from
the 50s, 60s, & 70s and control panels and consoles.
Author & Publisher - A Guide to Collecting Computers &
Computer Collectibles * ISBN 0-9684244-0-6
.
This isn't exactly what you're discussing, but . . . I've got, in my hand an
S-100 board, not fully populated, silkscreened
"North Star Computers, Inc.
Z-80A Processor Board Z80-A2"
I'll send this jewel via USPS Priority mail, as is, to the first person
whose $3.20 I get in the mail to cover mailing.
Dick
-----Original Message-----
From: Tony Duell <ard(a)p850ug1.demon.co.uk>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Wednesday, June 02, 1999 2:53 PM
Subject: Re: Northstar Horizon
>> > > And I need to bring up a terminal, or configure
>> > > something to function as a terminal.
>> > A PC with comms software is nice as you can use the logging feature to
>> > save scribbling notes as you bring it up.
>>
>> Except that it adds a few minor additional interfacing variables. If I
>> get NOTHING, would I assume that it's a problem with the N*, or could it
>> be configuring of HYPERTERMINAL? I think that the FIRST step, that of
>> getting a character or two through, would best be accomplished with the
>> simplest terminal available. I have a lunchbox machine; I should see if
>> it has a working serial port, and try something like PROCOMM.
>
>Having recomended a complex piece of test gear in another message, here
>I'll recomend something simple that I wouldn't like to be without - a
>'Christmas tree' type RS232 tester. One of those little in-line adapters
>with red/green LEDs on the major lines (TxD, RxD, RTS, CTS, DSR, DTR,
>CD).
>
>If I am ever bringing up an unknown machine which uses a serial terminal,
>I stick that on the port in line to whatever terminal I am using. Then I
>can tell if the machine is trying to send something as the TxD (or RxD,
>as appropriate) LED will flicker. Of course it'll also tell me if an
>unknown port is a DTE or DCE, and will help sort out handshaking problems.
>
>Although I have a lot of other RS232 test gear (several breakout boxes, a
>comms monitor, etc), I use this more than all the others put together.
>
>If you want to make one, all it consists of are those 2-colour LEDs (red
>and green diode in antiparallel) with 2 wires in series with a 3k
>resistor (3k3 would also work) between the above mentioned signals and
>Signal Ground. But they're pretty cheap to buy ready-made.
>
>-tony
>
Wouldn't you know it, I've got a non-functional pair of Expandorams as well. the first is an Expandoram, the second is an Expandoram II. Both were fully functional when I packed them in their wrappings some fifteen years ago, and boxed them but I think the switches may have gotten fiddled-with in the course of cleaning them. The memory IC's check out. Does anyone have doc's on the required settings?
thanx
Dick
>Please ponder this question.
>We either collect mainframes, minicomputers, or microcomputers. In the
>mix there is hardware, software, documentation, spares, and related
>material such as magazines, books, novelties. There might also be the
>original boxes.
>What percentage of your space is taken up by the hardware and how much
>by everything else? What is the ratio of actual computers to all the
>other stuff that goes along with them? Please tell me the catagory(s) of
>computer(s) you collect (mainframe, etc.), and what your percentages
>are.
I mostly collect DEC hardware -- easy since I worked at DEC for 20
years and was able to partake of DEC salvage when it was open. In
recent months I've started collecting in different directions, mostly
just things which strike my fancy. I can't say that I am trying to
collect any specific type of machines (other than the DEC ones), just
random examples of computers.
As for how much room it takes up... let me put it this way, my S.O.
and I live in one condo, my computers live in another (and I visit to
feed and water and work on them). The largest of the machines are the
pdp-11/10, pdp-11/34a and the pdp-8s. They may only take up 24sqft
of floor space, but they are 6' high, so they take up a fair amount
of volume.
I must say, however, that most of the stuff which takes up room are
all the boxes of manuals, handbooks, disks, spare boards, cables,
etc. that I have to keep them working.
So, I would say in my collection, about 30% to 40% of the space is
taken up by the actual machine collection, the rest is taken up by
the support stuff.
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com |
| Unix Support Engineering Group | (home): mbg!world.std.com |
| Compaq Computer Corporation | addresses need '@' in place of '!' |
| 110 Spitbrook Rd. ZK03-2/T43 | URL: http://world.std.com/~mbg/ |
| Nashua, NH 03062 | "pdp-11 programmer - some assembler |
| (603) 884 1055 | required." - mbg |
+--------------------------------+-------------------------------------+
Does anyone here have experience with AT&T 3B2 300 hardware/software?
I apparently have a pile of doc and software which is in complete disarray.
The software is all on 5.25" DSDD diskettes, and i'm not even sure if
i have what i need to format and reinstall an operating system. Does
anyone know what type of hard drives these computers support, or know
if the floppy drive can be upgraded to high density?
I have two base systems, one has either been cannibalized, or merely
every screw has been removed, since everything from the power supply
to the floppy drive is floating free in the case ;) The other unit appears
to be in much better shape.
The student chapter of ACM at the university here had these, so you can
imagine what sacrelige may have been comitted...
-Lawrence LeMay
lemay(a)cs.umn.edu
One of my dealers sent the following to his mail list. I thought this group
might be interested. Please contact him directly.
Paxton
We have an enduser client that is selling the following MV3100 systems.
They need an offer as soon as possible. (FOB Michigan)
QTY Part# Description
9 dv-470m-b9 MicroVax 3100/80
4 dv-31eta-a MicroVax 3100
3 dv-31btb-a MicroVax 3100
2 dv-31ct1-a MicroVax 3100
2 dv-31rta-a9 MicroVax 3100/95
10 vs48k-aa VaxStation 4000 VLC
*systems are complete, but we have no description of memory configurations,
hard drive sizes, etc., (licenses may become available, but if you are
interested, bid if no licenses are included)
** part numbers and descriptions provided by enduser - you may want to
verify
Contact:
Bob Frischkorn
Network Management Corp.
440-285-8400 or email netman(a)netman2000.com
If you are interested please contact Jim:
clmoving(a)jetnet.ab.ca or phone 780.594.7566
Jim told me it is working, has printer and disk drive, and THE ORIGINAL
BOXES.
Yours in good faith.
----------------------------------------------------------------------------
-------------------------------
Kevin Stumpf * Unusual systems * www.unusual.on.ca
+1.519.744.2900 * EST/EDT GMT - 5
Collector - Commercial Mainframes & Minicomputers from
the 50s, 60s, & 70s and control panels and consoles.
Author & Publisher - A Guide to Collecting Computers &
Computer Collectibles * ISBN 0-9684244-0-6
.
Hello,
recently I acquired a pdp11/70 in semi-working condition, but alas,
documentation for the console board was not included :/
Anybody here who is in the lucky position to make me some scans/copies, or
maybe someone knows where I can find 'em in digital (scanned) form ?
Thanks in advance,
Erikb.
Peroidically I do this in hopes of...
I have an IMSAI IMP48 SBC. It was given to me 20 years ago but not the
docs. I'd be interested in finding docs for it even if only a copy.
Allison
<> Please ponder this question.
<>
<> We either collect mainframes, minicomputers, or microcomputers. In the mi
<> there is hardware, software, documentation, spares, and related material
<> such as magazines, books, novelties. There might also be the original
<> boxes.
<>
<> What percentage of your space is taken up by the hardware and how much
<> by everything else? What is the ratio of actual computers to all the othe
<> stuff that goes along with them? Please tell me the catagory(s) of comput
<> you collect (mainframe, etc.), and what your percentages are.
<
<This is not an easy question to answer...
I collect SBCs, S100 and small dec systems (Robin, Pro, DECmate, pdp-8,
PDP-11, VAX) and the occasional odd (unusual) PC.
How much space, 150sqft room is cubed out. Also three steel racks plus
floor space(roughly 500cuft) in the garage. By actual count some 50
(may have missed a few) systems total. All but a small few are operable
or in use.
The key is that I collect a mix and if they have anyhting in common they
were the systems I drooled over when to were far to expensive to have bought
them all new.
Allison
Well . . . it seems to work, now that I've fiddled with the broken jumper
wire. The wire was broken but the insulation wasn't, and it was done so
neatly, I couldn't initially believe it was a user-installed jumper wire.
Now that that's done, I can put it in the "works" box . . .
Thanks for the help.
Dick
-----Original Message-----
From: Marvin <marvin(a)rain.org>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Thursday, June 03, 1999 7:04 PM
Subject: Re: VECTOR GRAPHICS 64K DRAM Card - switch settings?
> Richard Erlacher wrote:
>
> Would anyone be able to help me with this VECTOR GRAPHICS 64K DRAM BOARD's
> switch settings? The signals seem to be OK, but no data propagates from
> the thing. I'm not anxious to count through the combinations of
> settings.
According to the schematics for the Rev-3 board, S1 is the Bank Select with
positions 0 - 7 (or probably labeled 1 - 8) corresponding to D0 - D7. D0 -
D7 go through 74175 Quad D latches and come out on the Not Q outputs. These
are then all anded together (U41 - 74ls30) to output the Bank Select signal.
Hmmm, interesting, it looks like the inputs are left floating when the
switch is open, and I have a hard time believing that with LS type
circuitry.
There is a note indicating:
Jumper Memory Enabled
1 to 3 0000h - FFFFh
5 to 3 0000h - DFFFh
4 to 3 0000h - BFFFh, E000h - FFFFh
2 to 3 0000h - BFFFh
Would anyone be able to help me with this VECTOR GRAPHICS 64K DRAM BOARD's switch settings? The signals seem to be OK, but no data propagates from the thing. I'm not anxious to count through the combinations of settings.
thanx
Dick
Well . . . I'm going through all these piles of S-100 boards, see, and I put
the working ones in that box over there, see, and then I put the ones that
don't over in this box.
I've got this Jade Memory Bank and don't seem to have the doc's for it any
more either. . . and it has THREE switch blocks along with over a dozen
jumpers . . . it even seems to have an IC missing. . . .
Does anyone of you guys have any detailed doc's on this one?
Dick
-----Original Message-----
From: Erik Brens <ebrens(a)dds.nl>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Thursday, June 03, 1999 6:26 PM
Subject: Re: DEC pdp11/70 console docs
>
>> documentation for the console board was not included :/
>
> ^^
>Hello again,
>
>by "console board", I actually meant the front console panel (the thing
>with the switches on it).
>
>> Thanks in advance,
>> Erikb.
>>
>
I have a friend (Yes, Virginia, I have two friends) who's been a DEC
repairman for many years. He now wants to get rid of the accumulated a lot
of stuff in his barn, and has asked me to help get rid of it.
I'm not sure I have the time to make a complete catalogue of all his stuff.
Anyway, I know squat about big iron, and therefore don't know what's
valuable to people.
Please, therefore, email me with your wants -- anything from, "I'll take
anything" to "keep an eye out for this widget". I have no idea what he wants
for all of this, bit I doubt he's out to gouge.
manney(a)hmcltd.net
pgphoto(a)ragemail.com
P Manney
"Y1K caused the Dark Ages."
Thousands of discounted photo items at http://www.hmcltd.net/pgphoto
-----Original Message-----
From: Colan Mitchell <cdrmool(a)interlog.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Wednesday, May 26, 1999 4:37 PM
Subject: confidential info on old harddrives.
>
>If this is a ? thats been dealt with before I joined the list my
>apologies.
> I repeatedly come across personal and confidential information on
>discarded computers. I sit and shake my head in shock. Lawyers seem to
>be the worst. I have considered contacting the original owners and
>educating them about practicing safe hex but, especially in the case of
>lawyers and women, don't want to have them freak out and think I'm being
>weird and calling the police. On the other hand I feel that I should do
>something. In the end I just format the drives and forget about it.
> Has anyone experienced contacting an original owner? What was the
>response. This is something that I've not read about in the media as Y2K
>and Hackers get all the press but I suspect this is a bigger potential
>problem.
>
>
>Colan
>
>
>
>
>
> > Hi
> > Let me see, that is 384 machine pin sockets in 2102's alone.
> > Do you have a special discount that you might share?
>
Sorry to butt in, but I have a suggestion.
I use collet pin carries, these are metal carriers with machined
pins attached to them. You solder them on the board, remove the carrier,
then you have 16 nicely placed machined pins free standing. This allows much
easier inspection of the final solder joint since you don't have a plastic
dip case in the way, I buy them by the 1000 at about 5 cents each (14 pin
carriers, but you can get them any size) and that satifies all my socket
needs. If I need 16 pin,20 pin or 40 pin (rare) sockets I simply remove the
pins from a couple carriers and manually solder them. Also works well for
transistors, caps, resistors or what have you.
steve
>
> What percentage of your space is taken up by the hardware and how much
> by everything else? What is the ratio of actual computers to all the
other
> stuff that goes along with them? Please tell me the catagory(s) of
computer(s)
> you collect (mainframe, etc.), and what your percentages are.
>
> Thank you very much.
>
------------------------------------------------------------------------
----
.
Kevin,
I collect both micros and minis.
I'd estimate that a microcomputer constitutes about 40% of the bulk. The
documentation, software, and other pieces would account for the remaining
60%.
For a mini, the computer with necessary peripherals (drives, etc...)
probably account for about 80% of the bulk. Documentation, backup media,
and other stuff taking the remaining 20%. Often times, the "other stuff"
can be kept on top of the mini without impairing it's function. That
generally doesn't work with a micro.
Of course, I don't have the original shipping containers, pallets or
packing material for a mini. That would skew the numbers a LOT! :-)
Steve Robertson - <steverob(a)hotoffice.com>
If this is a ? thats been dealt with before I joined the list my
apologies.
I repeatedly come across personal and confidential information on
discarded computers. I sit and shake my head in shock. Lawyers seem to
be the worst. I have considered contacting the original owners and
educating them about practicing safe hex but, especially in the case of
lawyers and women, don't want to have them freak out and think I'm being
weird and calling the police. On the other hand I feel that I should do
something. In the end I just format the drives and forget about it.
Has anyone experienced contacting an original owner? What was the
response. This is something that I've not read about in the media as Y2K
and Hackers get all the press but I suspect this is a bigger potential
problem.
Colan
Has anyone ever tried ProComm?
It's a DOS terminal emulator that I use on an old Zenith SupersPORT 8088.
Here's the different terminal that it can emulate:
VT-100
TVI 920
TVI 950
VT-52
LS ADM5
HEATH 19
ANSI-BBS
ADDS VP
WYSE 100
IBM 3101
It's a pretty useful program, and doesn't take up too much space. I have it
on all of my old laptops.
///--->>>
-Jason Willgruber
(roblwill(a)usaor.net)
ICQ#: 1730318
<http://members.tripod.com/general_1>
I find myself without the necessary doc's to rewrite the BIOS for a system
using a small in capacity but 8" in size HDD. Would any of you kind and
resourceful souls have the necessary data on hand to help me out with this
task?
Thanx
Dick
The point about the "best piece of equipment" is perhaps the thing I like
best about using a logic analyzer for a difficult problem. It's such a pain
to set up, it forces you to think through the analysis before making any
measurements . . . or assumptions. Another nice feature is that you can
rearrange the displayed waveforms without rearranging the probes. If you
choose to see a signal set differently than you previously did, you don't
necessarily have to redefine your trigger equations or any such fun.
Dick
-----Original Message-----
From: Tony Duell <ard(a)p850ug1.demon.co.uk>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Wednesday, June 02, 1999 5:29 PM
Subject: Re: Re[6]: More Bringing up a CPM
>> On the subject of LA/scope/logic probe/voltmeter. I personally
>> consider a LA as the shot gun approach. It will often find
>> problems when one has no idea where to look. The only problem
>
>I can't agree with that. OK, so a logic analyser will monitor a lot of
>points at once, so you can test unrelated sections in the hope of finding
>the fault. But when you've got 64 or 128 or whatever traces, you still
>have to think about the fault.
>
>> is that someone with an oscilloscope can often have the
>> machine repaired by the time one gets the leads connected
>
>I've found that a small logic analyser (say about 3-4 channels),
>intellegently used, is very useful. It doesn't take long to connect it
>up. And it will tell you a lot about the circuit you're investigating.
>
>> I rarely use a logic probe because I don't have one. I
>> can use an oscilloscope just as well with the additional
>> features that an oscilloscope can provide when needed.
>> It is like a logic probe with more added.
>
>You _need_ a LogicDart :-)
>
>> Still the best overall trouble shooting tool I have is
>> an analog voltmeter. I can move quicker with one of these
>
>I agree. I use my old analogue meter a lot more than a digital one. It's
>a lot quicker to read an analogue meter for one thing.
>
>> than many can with other tools. As far as I'm concerned,
>> DVM's are only good for setting power supply voltages.
>
>Oh, they are also useful for setting voltage references on analogue
>subsystems. And checking the exact setting of a variable resistor (when
>you want to change it to (say) 3 time the value as an inital point in a
>modification).
>
>> I have one ( an accurate 5 digit unit ) but the analog meter
>> is still the first thing I reach for.
>
>There are 4 instruments that get most of the use on my bench. In order :
>
>An analogue VOM.
>The LogicDart
>A good bench PSU (30V, 10A). Useful for powering up subsystems
independantly
>A cheap handheld 'scope, audio band only. Useful for checking for PSU
>ripple, looking at motor drive waveforms, SMPSU waveforms, etc.
>
>
>> I find that most don't know how to trouble shoot. The
>> sequence is simple but many still don't get it:
>>
>> 1. Observe symptoms
>> 2. Make predictions
>> 3. validate predictions
>> 4. If predictions do not pan out add this
>> to the observed symptoms and go back to step 2 or 1.
>> 5. Repair bad part.
>>
>> I find that most don't understand the importance of steps
>> 2 and 3. They try to go from 1 to 5 and usually it doesn't
>> work. Step 2 does require that you understand what to
>> expect from each kind of failure.
>
>My method is related to that...
>
>1) Look for silly faults (cables fallen out, etc). Check fuses, etc
>2) Unless there's a very good reason, power up and observe the fault
>3) Do some standard checks. Check PSU rails, master clock, etc
>4) Think of possible causes for the observed symptoms
>5) Do tests (either execute commands or make measurements) to check out
>each possible cause.
>6) If no possible cause is the cause of the fault, you've missed one of
>the possible causes.
>7) You now know the bad part.
>
>The best piece of 'test equipment' you can have is a brain. _Always_
>think about the fault before trying to cure it. Often I make some intial
>measurements and then sit and think for maybe an hour before doing
>anything else.
>
>-tony
>
please see embedded comments below:
Dick
-----Original Message-----
From: Dwight Elvey <elvey(a)hal.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Wednesday, June 02, 1999 5:18 PM
Subject: Re[2]: More Bringing up a CPM
>"Richard Erlacher" <edick(a)idcomm.com> wrote:
>--snip--
>> The logic analyzer won't hide significant information about the logic and
>> timing. If you sample at twice the frequency of the fastest harmonic you
>> want to observe, you won't miss a thing.
>
> It is not just frequency issues. Levels can be a problem as
>well. I've seen circuits with mixed HC, LS, 4000 and other.
>You set the input for one and the other is wrong. Also,
>your 2X has to be twice the frequency of the response
>of the IC circuit and not just twice the clock speed.
>Also, the 2X sampling rule is only true for repetitive
>signals. This is a basic sampling law thing.
>100 Mhz isn't really fast enough to truly see what is
>going on in even an old 8080 processor board. Glitch
>catching helps but can still hide correct operation.
> Where I currently work, we are completely out of the
>ball park were current day LA's are of much use but
>that is another problem. We still have them and can,
>under limited conditions, use them.
>
I can assure you that you won't run into much CMOS circuitry in the old
IMSAI and Altair stuff. You're right, of course, if your instrument can't
be programmed to handle different thresholds then you could be persuaded you
see something you really don't, or perhaps be swindled out of seeing what's
really there. I remember looking at some new CMOS circuitry about 15 years
ago when the high-speed CMOS stuff was still new. It appeared, for all the
world, as though the outputs preceded the inputs of a series of gates by
quite a difference. I had set my 2467 display to the lower threshold of a
cmos schmidt trigger and displayed a couple of other signals with respect to
that, including the clock which triggered a sequence. It appeared that the
'Q' of a flipflop preceded the clock by quite a margin, perhaps 3-4 ns. We
quickly concluded that a sufficiently long chain would easily allow us to
read tomorrow's stock quotations today, thereby making us all rich. - - -
it didn't work that way!
The way I get around the random sampling error in observing a crystal driven
microprocessor circuit is that I use a little PLL to multiply the clock on
the board by some constant, say 4, 10, 16 or some such, and sample at that
rate as opposed to what the LA wants to use. That makes similarly long
pulses look similarly long as opposed to suffering from the temporal
distortion introduced by the asynchronism between the LA sampling clock and
the circuit on the board under observation.
Of course, like a 'scope or signal generator, you have to know how to drive
them, just as you must know how to interpret the results. The LA often
points up where to hook the 'scope. If it cuts my search through 60-70
signals down to half a dozen, it's made itself worthwhile.
I find the LA really handy for MCU-driven cirtuitry, since I can use the LA
to take a picture and then spiff it up and print it in the O&M manual.
What's more, with easily simulated FPLD's, it's really handy to compare the
simulation with what the LA sees. It's often quite heartening to see what
you thought you ought to see after working on one of those babies for a
couple of weeks.
In any case, I've troubleshot dozens of DRAM circuits with either the little
front-end sampling mux or a real LA, and have found them to be invaluable in
finding component failures, incorrenct jumpering, wrong delay lines, etc.
What's more, if I didn't make the mistake, I can prove it. If I did, I can
prove I fixed it. That's worth quite a bit of setup.
As far as frequency is concerned, the only problem I've encountered which
doesn't quickly show up on a LA display is metastability. As fast as things
run these days, and with the widespread use of fully synchronous circuitry,
almost everything goes into a device through a two-bit shift register stage
to mitigate metastability. I find that if I sample at twice or quadruple
the clock which drives the pipeline registers, I can catch everything I
need.
Those old circuits like the IMSAI and ALTAIR CPU circuits relied quite a bit
on circuits' propagation delays to build events. Races were common, and
that's why folks used to tack 20-400 pf caps all over those boards in hopes
of making them work better.
Like I wrote before, setup and interpretation is slow, painstaking, and
laborious. It's often wrong the first time. Unless you have half-a-dozen
similar boards to work on, it's hardly worth the trouble.
--- I8ABoogar(a)aol.com wrote:
> I have Two in great condition
What's the microprocessor? I used to have one of those when I was a kid. My
father might still have it in the attic (I know he has a box of those sorts of
things, but I don't know the exact contents, and he's several states away).
I recently saw a Mattel Baseball game at a Hamfest, but I've never seen the
Football for sale.
-ethan
_________________________________________________________
Do You Yahoo!?
Get your free @yahoo.com address at http://mail.yahoo.com
<I can't agree with that. OK, so a logic analyser will monitor a lot of
<points at once, so you can test unrelated sections in the hope of finding
<the fault. But when you've got 64 or 128 or whatever traces, you still
<have to think about the fault.
I'd also point out that if the LA in not connected into the system
correctly it can by virtue of ground loops and other things like the leads
actually induce problems. Seen that occur to people. same for scopes too!
I'm not saying they are bad but for some stuff you can end up looking for
the forest between the trees. the best example was a multibus design bring
up another engineer was doing and the board didn't do what was predicted
and of course it was surrounded with scopes LAs and even probes... the
problem...
8086 asm
MOV AH,Ah ( was supposed to move the immediate value x0A to
register A high byte!)
Them trees can hurt when the land of you.
Allison
<A Z80 will give useful patterns executing continual 00 (NOP, so the
<address bus cycles through all of memory) or FF (RST 38, so the stack
<builds down to fill all off memory). Both should provide useful patterns
<on DRAM control lines.
Indeed they do. If you want to force a pattern, the inbound bus buffer can
have pins lifted (if socketed). There are pleny of tricks before getting
out the "big guns".
For the cannons for ants set I do have a S100 Bus debugger that was use use
the phrase purpose built. It's a Logic analyser that has 4 leads floating
and 32 (address and datain plus data out) and a riot of controls so that
it's possible to do a bus level logic analysis and it has 16kx40bits of
2167 55ns ram to take a extended picture of things. I built it to deal
with the quad processor system as there were a lot of signals running.
<Like Allison I used to work almost entirely with a logic probe and a VOM
<(and a brain, which is the most important 'instrument' of all :-)). I had
<a good logic analyser, which saved me a lot of time on occasions, but it
<wasn't that convenient to use.
I have a 16 channel LA and two good scopes but often as not if I poke and
think as Dwight sugggested I rarely need to drag them out and set them up.
The most common use for the LA is craking "black box" devices and chips.
<I rarely use a 'scope for computer (digital) repairs. It's essential for
<analogue work, fixing SMPSUs, etc. But I don't find it _that_ useful on
<typical non-repetitive digital signals.
Depends, very handy for looking at some timing problems and general bus
havoc.
<Don't bet on it. I've lost count of the number of misdesigned (often
<subtly - like marginal timing or ground bounce problems) DRAM cards that
<I've had to sort out.
Those cards never worked, as in they often were unreliable or at best a
question. S100 cards generally were either solid or sick to my expereince.
It may have required running them for a day or two to see that they were
not good 24x7 designs.
<Also, a logic probe won't detect _some_ chip failures. You've got a 2
<input NAND gate. The logic probe shows nice pulse trains on all 3
<connections. You think it's OK and move on. What it hasn't told you is
<that one input does nothing, and the gate is a simple inverter on the
<other input. Yes, I've seen exactly that fault.
Same here, bad inputs are tough to shoot, though a chip clip (16pins 16
leds) does help here.
Allison