-----Original Message-----
From: Tony Duell <ard(a)p850ug1.demon.co.uk>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Thursday, 1 April 1999 9:14
Subject: Re: Collectors list
>> So, if you are willing to give your zip/postal code, in effect that is
>> an almost exact location of, at the most, a few hundred buildings
>> and often only a few dozen.
Good Grief.
5540 is my post code. But ours are not that specific.
In a big city they usually narrow it down to a suburb or two, but 5540
is the code for the entire city of Port Pirie. (15,000 people)
Comes from being less crowded I guess...
Geoff Roberts
Computer Systems Manager
Saint Mark's College
Port Pirie, South Australia.
Email: geoffrob(a)stmarks.pp.catholic.edu.au
ICQ #: 1970476
Phone: 61-8-8633-8834
Mobile: 61-411-623-978
Fax: 61-8-8633-0104
Does anyone know what the function of an IBM 557 Alphabetic Interpreter
is/was?
Looks like a punch card sorter of some sort.
Sellam Alternate e-mail: dastar(a)siconic.com
------------------------------------------------------------------------------
Don't rub the lamp if you don't want the genie to come out.
Coming in 1999: Vintage Computer Festival 3.0
See http://www.vintage.org/vcf for details!
[Last web site update: 02/15/99]
Does anyone know what an AD413B is? I've got a UNIBUS board with no
manufacturer, two berg connectors and this product code. Other marks are
the number 200225-03 on the solder side and "P/N 200791" on the component side.
--Chuck
Got a Panasonic HHC model RL-H1400 today for $5 with the printer and the
tray they both fit in. No power supply came with it so have not tested it
yet. Also got a box full cards, mb's, and cables for $2, have gone into yet
to see what all I have. Got a few other items today but they do not meet the
10 year rule. John
That's nothing. Me and a buddy broke all 10 of his toes with a PDP-11/44.
Was remarkably easy (and entertaining!) too. 44 is in a dual cab, weighs
~600 pounds. (I think... We never weighed it. It was REALLY FSCKING HEAVY.)
Anyway, we wanted to get it down a narrow hallway, but DEC, in their infinite
wisdom, fixed the rear wheels of the box so they didn't caster. So, we got
a handcart that had 4 wheels (2 up by the handle), laid it down, and manhandled
the 44 onto the cart. We start shoving down hall, 44 slides partially off
the cart and onto the floor. BUddy comes around the side to see if the box had
removed my fingers (I was in front), and has his toes under the box as he goes.
Did we mention the cart had a curved handle? Anyway, the weight of the 44
pushed the cart backwards, it departs the area at a high rate of speed, and
the box drops 6 inches onto his toes. We had a hell of a time removing the
machine from the hallway...
So, how badly did you hurt the hand?
-------
The classic example is an IC suspended over a PCB by means of the little
pieces of #40 wire which connect it to the circuit. They're not always a
terrible way to do things, and they've even been blessed by the analog
weenies at NatSemi, but their use in modifying or even building circuits
intended for some practical use is an abomination. Experimentation, well,
OK, but to use it repeatedly? . . .
Dick
-----Original Message-----
From: Bill Sudbrink <bill(a)chipware.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Wednesday, March 31, 1999 3:42 PM
Subject: RE: Kits vs ready-made (was RE: Rebirth of IMSAI)
>> the shoddy technique (air-wires, etc) made for problems which couldn't
>
>I'll bite. What's an "air-wire".
>
Unfortunately, in today's climate ("NOTHING's MY fault!") people buy a kit
with the assumption that the seller will provide whatever expertise is
required to assemble it correctly. That was not the case 20 years back.
This kind of handholding is frustrating and costly.
A degree in engineering isn't sufficient qualification, either. Some of the
crappiest work I ever saw while in the aerospace industry, was by fairly
senior engineers. The excuse was that "it's not a deliverable," but often
the shoddy technique (air-wires, etc) made for problems which couldn't
readily be explained, but which didn't occur when a competent technician
built the same circuit.
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, March 31, 1999 2:03 PM
Subject: Re: Kits vs ready-made (was RE: Rebirth of IMSAI)
>> I claim the other way around. Most kit suppliers have to spend _more_ on
>> technical support because they have to help people who try kits too hard
for
>> them and expect the supplier to sort out their mistakes.
>
>On the other hand, I don't suppose total newbies (you know, the sort of
>person who has problems inserting Disk 3 because the drive is already
>full with disks 1 _and_ 2) would even attempt a kit...
>
>-tony
>
>You can also use a Unibus host + a DW11B + a Q-bus backplane with CD
>interconnect. The VSV11 was one of the devices _supported_ on the DW11B
>(and the combination was called a VS11 IIRC).
Good point... also, is there any support for it on uVaxen?
>I have the VSV11 prints - I came across them earlier today when I was
>looking for the VT11 stuff for Megan. I also found some 11/780 prints
>(Unibus interface and WCS option prints, I think)
I could use a copy of the prints... I have a VSV11 board set at home,
but no joystick for it...
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 would require a variable length or variable preset counter sourcing th
<clock. The problem was knowing when it was going the generate an M1 cycle
I used a shift register and an or gate.
<counts. Either that or you'd have to look for the clock edge after the
<appearance of the M1 strobe and KNOW it wasn't part of the interrupt
<acknowledge. Neither was thrifty with logic, nor was it fun.
M1 made it easy. the logic was if M1 then hod clock one cycle.
<I had one friend whose NorthStar convinced me every time I saw it, that I
<didn't want one. We were using CP/M, and you really didn't have even one
<byte to spare in your measly 64K. His NorthStar only had 48K of memory
<space, for some reason. Maybe it was because they'd mapped that region fo
Funny mine has 56k to the base of BDOS. The trick is CCP and BDOS resides
below the controller at E800h and the BIOS in the 4K at F000h. I also
have a PROM burnt for F800 (trivial). The first banking scheme I did had
mappable 4k pages in the F000h space. Very nice really. Later I went
softsector using a uPD765 (I worked for NEC sooo...) and pulled the hard
sector controller.
Allison
] Having secured a copy of Tom Pittman's Tiny BASIC on paper tape
] (autographed by the man himself!), I'm in the process of adding a
] teletype simulator to the COSMAC Elf simulator. It's a bit strange
Without knowing anything much about ASR-33's in particular, but
having done bit-banging serial stuff before, here are my best
guesses.
Do you have any delay on the recieving end that could make it
miss the beginning of the next byte? The reason for the stop
bit(s) was to give the reciever time to do something with the
byte that came in, before the next byte started arriving. If
the reciever needs more processing time, then the sender should
include more stop bits. (In the real world, I've never heard
of needing more than two stop bits.)
Also, bits typically don't have any space between them. So,
for instance, you should not return to '0' between sending two
'1' bits. Between bytes, a reciever will typically watch for
a falling edge to know when a start bit has begun. So if you
return to zero even for an instant between two stop bits, the
reciever may interpret that as the start bit of the next byte.
And of course, between bytes, the line has to remain at '1',
or risk looking like a start bit.
Good luck!
Bill.
