Maybe we're talking about two different things, Sam. I thought we were
going to put forth a specification for participants to code for whichever
processor they wanted or both, just to see which one came out fastest,
smallest, or whatever...est.
You were the one who mentioned the graphics so one could see what was going
on. What I had in mind was a computation, e.g "compute the product of three
M x N x L matrices, where M, N, and L are <127, containing prime decimal
numbers of not more than 511 and not fewer than 256 digits each".
An environment has to be selected for a task like this. You know what I
mean. There has got to be some limit on how much a process is helped or
hindered by the environment.
Dick
-----Original Message-----
From: Sellam Ismail <dastar(a)ncal.verio.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Saturday, April 17, 1999 4:15 PM
Subject: Re: z80 timing... 6502 timing
>On Sat, 17 Apr 1999, Richard Erlacher wrote:
>
>> Let's not start throwing up our respective hands in disgust! Nothing's
been
>> attempted yet. In fact, nothing's been suggested yet except a couple of
>> things which at first inspection didn't seem like they'd work. Now, Hans
>> Franke suggested something like a KIM-1. There's no reason one couldn't
>> code for something LIKE a KIM-1, even the guys working the Z-80 side, but
>
>You want people to have to learn 6502 in order to participate in this?
>So, I've never touched a Z80, but conversely you'd want me to have the
>added burden of having to learn Z80 assembler if we chose to do this on
>the Z80?
>
>I think part of the idea is to implement this exercise on different
>processors so that we can all collectively learn how the code to perform
>the same algorithm works on the many different varieties.
>
>> it's inappropriate to choose. If one wants the hardware, it should be
the
>> SAME hardware throughout the exercise, though. That's why I was
suggesting
>> a simulator. All that's really needed is a run to see if it actually
will
>
>Ok, Richard. You go off and write this simulator, and design the board to
>run it. Then when you're all done with this masterpiece, the rest of us
>will have long been done with this little mental challenge and talking
>about something more contemporary, like how two years prior the world
>did not in fact end on the January 1, 2000.
>
>> execute and end up with the desired result when code is submitted to the
>> hardware. A simulator would be adequate so long as it was trusted to
give
>> honest timing results. That way, nobody would have to risk burning his
>> fingers.
>
>I think counting clock cycles would be a lot simpler, but that's just me,
>always trying to find the sensible solution.
>
>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: 04/03/99]
>
I want to distance myself from the majority of this nonsense. Building a
simple computer with a processor, a ROM, a full compliment of RAM, and a
serial console interface is a 10-minute design and a 90-minute fabrication
task. If it's designed to fit already existing firmware/software, it's even
more or less practical to fit it into that firmware or software's
understanding of what the hardware is that fits with it. That means that an
operating system might be straighforward to accomplish in a day or two if
there's software in the form of a decent monitor or OS to support it.
HOWEVER, since there's little hardware support commonly applicable to both
of the subject processors, let alone for a number of others, It's silly to
consider anything but the simplest of hardware for a real-world
implementation. I'm sure most people in any way familiar with the things we
had to do back in the '70's will agree, that, from a hardware standpoint,
building a single-board system with 64K SRAM, Whatever size of EPROM you
like, overlapping it and disabled when copied into RAM, and a serial port is
a no-brainer, requiring , as I previously said, about 90 minutes to
wire-wrap. It might take longer if you have to find the parts. If you use
a WD FDD/HDD card, it will take another 15 minutes to wire up the cable
interface. If, however, you use just a WD1770 or 72 you have a floppy drive
as well. For the Z-80,that means you have CP/M. I don't know what's
comparable for 6502 development.
If you simply stop after the serial console interface, say,a 16C450 off an
obsolete but otherwise healthy PC serial board, you've got enough to run a
decent debug monitor. I have a couple for the 6502, though I was wanting to
incorporate the assembly/disassembly functions as well. That hasn't
happened yet, and until I'm properly motivated, probably won't.
Now I can't imagine why a graphics display, or anything so inane as that
could creep into the consciousness of an otherwise perfectly sane person
wishing to deal with one of life's fundamental mysteries, i.e. "which is
really faster, the XXXX or the YYYY?"
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: Saturday, April 17, 1999 7:40 PM
Subject: Re: z80 timing... 6502 timing
>> Well, while you're at it, why not add a hard drive,
>
>1 or 2 chips for a SCSI interface...
>
>> a graphics accelerator,
>
>More nasty, at least if you want to keep it 'classic'. If I'm allowed
>bit-serial (like the MG1), perhaps a couple of dozen TTL chips at most.
>
>> a scanner,
>
>See above for a SCSI port
>
>> an ethernet adaptor,
>
>Oh, 3 or 4 chips...
>
>> a pencil sharpener,
>
>PIA chip + relay driver + relay to control sharpener motor.
>
>> and a juicer attachment?
>
>Ditto.
>
>>
>> Jesus Christ! Can't anything be simple for you, Richard? This is a
>
>You call that _complicated_ :-) :-)...
>
>-tony
>
'nuff said?
I saved a pair of these critters at the Paxotn auction, now need some docs
so I can figure out exactly what I'm dealing with here.
-jim
---
jimw(a)computergarage.org
The Computer Garage - http://www.computergarage.org
Computer Garage Fax - (503) 646-0174
>>> Coming soon to www.computergarage.org - the CBBS/NW on-line archives
>>> Coming to VCF III (2-3 October 1999) - CBBS/NW live!
--- Lawrence LeMay <lemay(a)cs.umn.edu> wrote:
> Well, I didnt say that I would pay $100... Or that it was a great price.
> But it might be a fair price.
>
> And i'd probably try to locate Lassiter and see if my some miracle he
> could repair the board, etc.
I don't get the reference.
> But, thats just me. To me, having a PDP8/e is the ultimate dream machine.
> That, and having the room to store a PDP8/e...
A PDP-8/e isn't all that large. Some of the peripherals can cause a
space problem...
-ethan
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--- Marvin <marvin(a)rain.org> wrote:
>
> The only real measure I have seen is on ebay, although others can talk about
> what goes on in the newsgroups. The last PDP-8i core stack ended at $76.00
> with 14 bids and the reserve was not met. The URL is:
>
> http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=91272199
>
That's me. I had the high bid. The reserve was $100. The seller is willing
to sell to me first if I pay the reserve amount. I personally was not unhappy
when the price was around $50. I didn't _really_ mind $76, but at $100, I'm
forced to consider it hard. I mean, I already *have* working core, several
stacks in working machines. I don't _need_ this, thus the debate.
Thanks,
-ethan
_________________________________________________________
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At 11:52 AM 4/17/99 -0700, Ethan Dicks wrote:
>I am attempting to back up some floppies from a project I did a few years
ago.
>The sets of 3.5" 1.44Mb IBM floppies have been stored in a box, in a cool and
>dry room. Out of one set of 12 and one set of 15 disks, I have four disks
>that have read errors that DOS won't get past, bad sectors and the like.
>
>Are there any tools to go divining on DOS floppies that work better than
>an endless succession of "R"etries?
Try several different drives on different machines. Drives can be
out of alignment with respect to each other, and this includes the
machine that wrote the disk as well as the machines that read them today.
Try reading them on other types of machines, like Macs or Amigas with
proper DOS-reading abilities. Another good trick is to hold the disk
between your thumb and first finger, then whack each edge on the table-top.
Also, get out the can of compressed air to clean out each drive before you
try this, and open the shutter on each disk and blow them out, too.
- John
--- John Foust <jfoust(a)threedee.com> wrote:
> At 11:52 AM 4/17/99 -0700, Ethan Dicks wrote:
> >I am attempting to back up some floppies from a project I did a few years
> >ago.
>
> Try several different drives on different machines.
Done. Used a *new* drive in case my regular drive was dirty, too.
> Try reading them on other types of machines, like Macs or Amigas with
> proper DOS-reading abilities.
That was my next trick. The Amiga reads disks strangely (one track at a
time in MFM mode, then converts MFM to binary data by using a portion
of the graphics hardware to run a miniterm transformation on the buffer;
it uses a 4096-bit shift register in the sound chip to slurp up the track
in the first place, the major reason why C= sold 1/2-speed high-density
drives that work on Amigas going back to 1985 with no hardware modifications).
I'll try the Amiga route this week.
> Another good trick is to hold the disk between your thumb and first finger, >
then whack each edge on the table-top.
I've done that. My question is, how does that work?
> Also, get out the can of compressed air to clean out each drive before you
> try this, and open the shutter on each disk and blow them out, too.
I typically blow gently on the open shutter, being *very* careful to keep
the airstream dry. I am not blessed with a collection of canned air.
Thanks for the tips,
-ethan
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This is sort of a heads-up. Even though I am the actual "seller", I'm
really putting this item up for a close friend. I'd buy it myself if I
could, but I'm in an anti-aquisition mode myself. It's an OSI Challenger 1P
computer + documentation
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=93182204
There are some nice piccies even if you're not interested in bidding.
HI to all :)
A
When I mentioned the chance to buy a 4kW stack for the PDP-8/i for $100...
--- Lawrence LeMay <lemay(a)cs.umn.edu> responded:
> Actually, that's probably a reasonable price.
Foo!
> Core memory boards, probably non-working, have been going for a high price.
I got sniped for a PDP-11 double-core stack this weekend, backplane included,
that went for $38, no reserve.
> Age and a nice visible setup increase the price.
The core stack for a PDP-8(i|L) is older than much of what's on the
market, but none of the good stuff is visible at all on it.
> Now, I havent seen the memory in question. but the pdp8/e core
> memory i've seen is all covered by a clear plastic shield. This
> increases its value as a display piece, as you can easily see
> all the core, and its all protected.
It's hard to describe the arrangement, but the core plane in question
here is a block with two edge-connectors on either side, "dual-height"
as they say, but it's much thicker - let's try bad ASCII art to illustrate...
######## ########
xxxxxxxxxxxxxxxxxx == ######## ########
######## ######## ######## ########
core planes paddle-boards with wire harness
The outside of the core plane part is covered in a "diode matrix", with
a wad of twisted-pair wires that go off to paddle-boards, one for the
sense bits, one for the inhibit bits. The address lines come up the diode
boards, the data comes up and down the paddle-boards.
There are several PCBs with core in the core stack, 4-bits per layer with
an optional parity layer that has one pad of bits and three pads of core-less
X-Y wires. None of this is visible when the plane is assembled, and it's
soldered together with lines of wires going up and down the planes.
> Of course, in order to use the core on a pdp8/? you would need
> a couple of support boards in addition to the core plane board
> itself. I would say that just the core plane, being of a nice
> size, and being very good 'visually' to display, and somewhat
> because its a PDP8 series board (nostalgia value), that its
> probably worth $100 all by itself. If it comes with the 2 support
> boards and the top connector things at that price, then i'd say
> its a bargain.
You are thinking of newer hardware. The pre-OMNIBUS 8's have a wad of
individual, single-height cards that contain the sense-amps and the inhibit
drivers. I have a pile of them from an -8/L that someone else had already
begun to strip for parts before I bought it (it also happens to contain the
only DEC lock that does *not* use the XX2247 key). I'm not worried about
the analog stuff... I need the core.
Of course, as Allison pointed out, I could always stick in a lump of battery-
backed static RAM. I was contemplating building a wiring harness to adapt
an RX8E on the back of either an -8/L (which has 8kW of core out of 12kW in
an expansion cabinet) or on the -8/i. I would use berg connector pins to
stick the wires on the back side of the backplane (to avoid soldering, of
course; but worst case, I just wire-wrap on a connector or two and use
sheilded ribbon to move the signals around.
The joys of restoration in a market of scarcity. :-P
-ethan
_________________________________________________________
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In my limited experience with the PDP-8E, memory seems very difficult to
come by. I'd give my eye teeth for a 32k semiconductor board, but both
semiconductor and core seems to be nowhere.
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: Monday, April 19, 1999 7:05 AM
Subject: How scarce (valuable) is core for the PDP-8?
>
>I have a chance to buy a 4kW core stack for the PDP-8/i (-8/L). It's
>more than I want to pay, $100. My question is, what are these things
>going for these days? I don't really *need* it. The guy selling it
>has more core than this that he saved from a "recycler", but he's in
>it for the money, not out of a love for classic machines. Most of his
>memory, he sells to people who want something to stick on the shelf and
>"ooh" and "aah" at. :-(
>
>So... for those people who have been trying to get core over the past year
>or two, what's it costing? I'm trying to decide if I want to grab this
>stack to put into my -8/i and bring it up to 8kW, an entirely optional
>project (I have all the other parts I would need for the upgrade from a
>PDP-8/L that I got in 1982 that was sold as parts-only, bad core, and most
>of the I/O and part of the CPU missing).
>
>I think he's charging too much, but maybe I'm disconnected with the
>current pricing. I do know that if I pass on it, there are several
>other people who are waiting for this exact piece, so it'll be sold
>one way or the other when I answer him.
>
>OTOH, I do have a broken (20-30 fractured cores) -8/L stack that I've
>contemplated repairing. It's a parity stack, so I can scavenge wire
>and cores from the parity plane (or just use the parity plane intact
>as another bit, then use one pad of broken core to repair the other,
>less damaged pad of broken core). Any thoughts out there on core repair?
>It's 1968 DEC core with, AFAIK a seperate sense and inhibit wire, which
>is both good and bad - good because the cores are larger than three-wire
>core, bad because I'd have to thread up, down and two diagonals.
>
>Of course, I could always sell the broken plane to a collector and use
>the money to fund part of this working stack. So many options. In terms
>of time spent, it's cheaper for me to work a few hours and earn the money
>that the core pirate wants; in terms of lessons learned, repairing a
30-year-
>old core stack would be a big thrill, *if* it worked.
>
>Thanks,
>
>-ethan
>
>
>_________________________________________________________
>Do You Yahoo!?
>Get your free @yahoo.com address at http://mail.yahoo.com
>
>
I'm not sure about the problem you're having with HDToolbox, but what type
of HD controller is in your 2000HD? I remember having problems similar to
what you're experiencing (old Mac SCSI drive not recognized by OS) when I
was using a 2090a in my 2000. When I switched to a 2091, I had no further
problems.
I think the 2091 was standard in the 2000HD, but it might be worth checking
to see if someone has swapped in an old controller...
Just a thought. Good luck.
Mark.
----------------------------------------------------
Amiga / Apple / NeXT / PDP-11 / PS/2
Computing happily on the trailing edge of technology
----------------------------------------------------
At 07:25 PM 4/17/99 -0400, you wrote:
>
>Well, I know about HDToolbox, but there's one problem.
>
>When I try to run HDToolbox, it always says "Driver not installed" in the
>box that is supposed to contain drive information. The HDSetup program
>will get to the point where it is supposed to start formatting &
>partitioning the drive, then just drops back to WorkBench with no
>messages.
>
>Any ideas for this one?
>
>Thanks,
>Kevin
>
>Did something fall into place here for me?
>Does the "RT" in RT-11 happen to stand for Real Time?
It sure does...
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 |
+--------------------------------+-------------------------------------+
The mode in which the Shugart SA1400 controllers, after which some of
XEBEC's controllers were patterned, was this ultra-simple model. That may
not have been the only mode, but I've got an 8" drive controller which seems
to work in this way, as it also has no device address switch. I've never
found the identifying logo or whatever, but the S-100 adapter I got with
this setup has a PROM marked "SA1400."
I've also read about this single-target-single initiator mode in the early
papers we used in establishing the SCSI-I standard back in the mid-1980's.
( I had the "privilege" of sitting through a number of the standards
committee meetings on behalf of my employer back then) Clearly, SOME makers
had used this as an operating mode. Multiple disk drives were not that
common among small systems back in those days.
Dick
-----Original Message-----
From: Eric Smith <eric(a)brouhaha.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Monday, April 19, 1999 12:07 AM
Subject: Re: Ancient disk controllers
>> SASI, incidentally was essentially a
>> Single-Target-Single-Initiator SCSI so it wouldn't need a device ID
switch.
>
>SASI supported eight targets. Since there was only one initiator and no
>disconnects, the initiator didn't need an ID. But the target devices still
>needed IDs.
>
>SCSI-1 added arbitration (for multiple initiators), disconnects (and
>reselection), and the 10-byte commands (to support larger devices). I'm
not
>sure whether SASI supported the message phase; that may also be a SCSI-1
>innovation.
>
>Usually a SASI host can deal with SCSI disk drives. Sometimes a SCSI
>host can deal with SASI targets, as long as it restricts itself to the
>SASI commands.
<My dumb question: What is a real time operating system?
<
<Hans Olminkhof
Complex question simplified answer.
An Operating system (environment) that supports tasks that must keep up
with real world events. Timeliness is the key element, either now or within
a known time for actions to occur are often part of the
specification typical use might be process control where pressure,
temperature and ??? are monitored and adjsted to stay withing bounds or
require extremely fast reaction to abrupt changes. Things
that RTOSs have are interrupt driven events and scheduling of lower
priority events for less demanding tasks.
RTS-8 (DEC pdp-8) (sources and docs on the 'net)
RT-11 (dec PDP-11)
Two commercial examples that are well known.
CP/M and believe it or not DOS (there are DOS look alikes that are RT)
can be as well.
Allison
--- Pete Turnbull <pete(a)dunnington.u-net.com> wrote:
> On Apr 19, 5:58, Eric Smith wrote:
>
> > Usually a SASI host can deal with SCSI disk drives. Sometimes a SCSI
> > host can deal with SASI targets, as long as it restricts itself to the
> > SASI commands.
>
> Some old SCSI hosts can, but most modern ones expect to use messages.
I have an ancient driver for monochrome Macs that can be set to old
SCSI<->ST-506 bridges like the Adaptec 4000-series or even a couple of
SASI controllers.
I know I've seen one SASI<->ST-506 bridge - inside the Commodore PET
D9060/D9090 hard drives. There's a Tandon TM602S (or TM603S) inside
the box, a SASI interface to it, then a Commodore "DOS" board that
speaks SASI out one end, IEEE-488 out the other. One of these days,
I'll disassemble the ROMs on the D9060 and look for the part that
reads the 5Mb/7.5Mb jumper and sets up the drive parameters, then patch
in the right numbers for an ST-225 so I can continue to use the thing
after my last 5Mb mechanism dies.
-ethan
_________________________________________________________
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Get your free @yahoo.com address at http://mail.yahoo.com
>> I've installed a filter at my end that should dump most, if not all,
>> messages with OT: in the subject line. However, the point remains that I
>> should not have had to do so in the first place.
Hmm, the problem with that being that occasionally OT conversations are
interesting/meaningful.... what we need is a filter that only starts
dumping OT threads after the first few messages (enough intelligence to
never let *any* 'my language is better than yours', gun laws, ABS
braking etc etc. conversations through would be great too.... :*)
(Hmm, maybe that sounds a bit heavier than it should be... still, it is
Monday morning... ;)
cheers
Jules
>
On Apr 19, 5:58, Eric Smith wrote:
> SCSI-1 added arbitration (for multiple initiators), disconnects (and
> reselection), and the 10-byte commands (to support larger devices). I'm
not
> sure whether SASI supported the message phase; that may also be a SCSI-1
> innovation.
It didn't; messages first appeared in SCSI-1.
> Usually a SASI host can deal with SCSI disk drives. Sometimes a SCSI
> host can deal with SASI targets, as long as it restricts itself to the
> SASI commands.
Some old SCSI hosts can, but most modern ones expect to use messages.
--
Pete Peter Turnbull
Dept. of Computer Science
University of York
For those who have never witnessed the diversity and chaos that has been
Paxton's warehouse, pictures taken today during the auction are available at:
http://www.computergarage.org/Garage/Paxton/P0??.JPG (where ?? = 06 thru 42)
The last few are shots of the collective bootie that the local gang took out.
(and yes, its as chaotic as it looks in the pictures!)
I'll probably arrange it into a more normal web page in the next few days.
For my part, I managed to nab a pair of HP 1000F minicomputers (CPU
cabinets only), a Tek 4006 terminal, a DEC TU-81+ tape drive and RA-81 hard
drive, a Freiden computerized postage scale, a case of toner kits for DEC
LN-03/Scriptwriter printers, a Tektronix Type 230 'Digital Unit', an
HP-9000 computer, a DEC MINC-11, and some other assorted goodies.
20 points extra if you can tell us why the unit in this picture:
http://www.computergarage.org/Garage/Paxton/P049.JPG
had enough significance to rank fairly high on my 'nab' list...
More to come...
-jim
---
jimw(a)computergarage.org
The Computer Garage - http://www.computergarage.org
Computer Garage Fax - (503) 646-0174
Tim Shoppa wrote:
>Some real-time operating systems can be pressed into service as
>general-purpose multi-user OS's. For example, RSX-11M. Others
>make quite nice single-user development platforms - for example RT-11.
>
Did something fall into place here for me?
Does the "RT" in RT-11 happen to stand for Real Time?
Hans Olminkhof
See my one comment embedded below, plz.
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: Sunday, April 18, 1999 2:08 PM
Subject: Re: z80 timing... 6502 timing
>>
>> I want to distance myself from the majority of this nonsense. Building a
>> simple computer with a processor, a ROM, a full compliment of RAM, and a
>> serial console interface is a 10-minute design and a 90-minute
fabrication
>
>Less than that, actually. There's nothing to 'design' IMHO - just stick
>the chips on a piece of wire-wrap board and wire-wrap the address and
>data buses. While you're doing that, design the address decoder with the
>other half of your brain.
>
>I built a 6809 SBC years ago, and the chip count was pretty minimal.
>IIRC:
>6809 CPU + 4MHz crystal as the clock
>2 off 6264 RAMs (16K RAM total)
>2764 EPROM and space for a second one
>6551 + MAX232 serial port
>9914+75160+75162 GPIB port (that was in the spec, obviously not needed
>for a general-purpose machine).
>2 off 74LS138 address decoders (one to divide the memory map up into 8K
>blocks, the other to subdivide one block for the I/O chips). These days
>I'd use a GAL.
>A couple of TTL latches and buffers for I/O ports (cofig switches, status
>LEDs, etc).
>
>That was it. Obviously a 6502 could be used with much the same hardware.
>A Z80 wouldn't be any worse either.
Rockwell made a 65C102 available in the same speed grades as the 65C02.
This used a quadrature clock just like the 6809 and worked pretty much like
it as well, at least insofar as the timing circuit was concerned.
>> Now I can't imagine why a graphics display, or anything so inane as that
>> could creep into the consciousness of an otherwise perfectly sane person
>> wishing to deal with one of life's fundamental mysteries, i.e. "which is
>> really faster, the XXXX or the YYYY?"
>
>Oh, Sam was suggesting all sorts of complex features and I was pointing
>out that most of them weren't that hard to add if you really wanted them.
>You don't want them for this challenge IMHO.
>
>-tony
>
That's what y ou have to do when you start with nothing. It's not a new
concept.
Dick
-----Original Message-----
From: Mike Ford <mikeford(a)netwiz.net>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Sunday, April 18, 1999 2:10 PM
Subject: Re: z80 timing... 6502 timing
>>Sure! Let's have a driving contest to see who can drive the fastest, but
>>first we all have to build our own cars. THAT MAKES AN AMAZING AMOUNT OF
>>SENSE!
>
>Shsssh! We're building a race track first.
>
>
please see the embedded comments below.
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: Sunday, April 18, 1999 2:05 PM
Subject: Re: z80 timing... 6502 timing
>>
>> If one were going to put an FDC in place, the easiest probably would be
the
>> WD3765, since it has built in cable-drivers and receivers as well as
>
>Sure. Or one of the similar, but incompatibly pinned-out UMC disk
>controller chips.
>
>Heck, it wouldn't be hard to add one of the multi-I/O chips from a PC I/O
>card and have FDC, 2 serial ports and a printer port. Most of them only
>need an 8-bit data bus for those functions.
>
>> clock/data processing hardware. You connect it directly to the cable, as
I
>> recall. It otherwise behaves as a uPD765 (i8272).
>
>Absolutely. The point I was making (not very clearly) is that WD FDC
>chips are getting hard to find, but there's no reason not to use an 8272
>(or one of the later chips based on this, but with more things integrated
>into the device).
>
>But if you insist on 'classic' hardware (meaning all the chips you use
>were in production at least 10 years ago), you probably won't be allowed
>to use some of these more integrated devices.
That's exactly the reason I'd prefer to use the WD1002 boards I have around.
They handle both the FDC and HDC functions with a minimum of extraneous
hardware and would, at least in the case of the Z-80 lead to a productive
OS. That's not as likely in the case of the 6502, since there wasn't much
of use around for it. Nonetheless, a nonvolatile storage medium of some
sort would be convenient, and if I make the board in question home to both
processors there'll be no doubt about whether one or the other has more or
better resources. I got these boards in 1982. When they were brand new
products and, in the case of the 1002's, before they were released
commecially.
>-tony
At 09:18 PM 4/18/99 -0700, you wrote:
>
>In case anyone's wondering what everything is in the pictures Mr. Willing
>took at Paxton's auction, I've identified as many things as I can so that
>if anyone ever spots one of these in their travels and wonders if its
>worth their while to pick up, they'll at least have an idea what they're
>looking at.
<snippage>
> P023.JPG 17-Apr-1999 22:02 64k
>
>Damn it! Damn it all to hell! That's the HP 9000/520 Unix workstation
>I've been lusting for!! Frank McConnell has the only one I've ever seen.
Well then, you're gonna hate me! It followed me home! (or at least, will
as soon as I get back to pick it up!)
> P024.JPG 17-Apr-1999 22:02 73k
>
>Tektronix 4001 (or 4002?) storage scope.
Well... I thot it was a 4002 as well... It is a 4006-1. It followed me
home too!
> P044.JPG 17-Apr-1999 22:03 79k
>
>Is this the HP1000F? I thought you said it was an empty chassis.
No, I said I got the CPUs only (as opposed to a complete system). P044.JPG
is the rear of the unit, P045.JPG is the front. B^}
-jim
---
jimw(a)computergarage.org
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