>> And, of course, a zero millisecond seek time.
>I thought there was a small time (<<1ms) for the read amplifier to settle
>down after a head switch. In other words, the 'seek time' (really the
>head switching time) was very small, but none-the-less measurable.
True, but of no consequence as long as the head switching time is less
than the time it takes to spin through the intersector gap. According
to my RS03/04 docs, there's enough time to make such a switch between
sectors.
What I always found interesting about the RS-series drives were the
write-protect switches. You can set six on/off switches to the
binary number specifying the highest (of the total of 64) tracks
that you want write-protected.
--
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
Usually. It depends on where you find them. XT's go for around $15 -
cinder blocks go for about $1-$5. It depends on what you want. The ones I
got were pick-and-choose from a demolition site. I had to chip off some
chunks of cement and such, but I think it was worth it.
///--->>>
-Jason Willgruber
(roblwill(a)usaor.net)
ICQ#: 1730318
<http://members.tripod.com/general_1>
-----Original Message-----
From: Fred Cisin (XenoSoft) <cisin(a)xenosoft.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Sunday, May 23, 1999 5:24 PM
Subject: Re: Space, the next frontier
>where you are, are cinder blocks cheaper than XTs?
>
>
>Well the RS11 with no suffix is just the controller but since yours has a
>motor and a "W" serial number it sounds like one of the fixed head disks
>for the RF11. I'm guessing that the tube would connect to the air
>filtration system. I've not had much luck locating a picture for
>comparison. I'll bet you any amount of money if you were to open it you
>would find a single platter attached to that motor inside the housing
>and a pair of read/write heads.
^^^^^^
*A* pair? It's a fixed head disk of 64 tracks, so I'd expect 64 such heads!
RS03: 64 tracks, 64 sectors/track, 64 words (128 bytes) per sector.
RS04: 64 tracks, 64 sectors/track, 128 words (256 bytes) per sector.
An RS03 actually has 4 spare tracks and a timing track, while the RS04
has 8 spare tracks and a timing track, with (of course) a set of heads for
each track.
And, of course, a zero millisecond seek time.
--
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
<RAM16 A3 board in the machine currently. Then I'll have 56k. Perhaps
<then I'll be able to load and use CP/M 2.2. =-D
CPM needs memory starting from 0000h. and dependinghow is was sysgend or
move'd anywhere from 20k all the way up to E800h (base of the FDC).
Currently the only version of CPM I have for the NS is V1.4 for the single
density controller. When I went to CPM2.2 I used a different controller.
The upside is there is burried on the WC CPM cdrom a few BIOSs for the NS*
controller.
Allison
Heads Up......
Conteact the person directly by e-mail if interested.
---------- Forwarded message ----------
From: bobm(a)istal.com
Newsgroups: rec.radio.swap
Subject: COMMODORE
Date: Sun, 23 May 1999 21:13:27 GMT
I HAVE SEVEN BOXES OF COMMODORE COMPUTERS AND ASSOCIATED ITEMS
INCLUDING SEVERAL VIC 20'S, C-64, NEW 128, NEW DRIVES,NEW TAPE DRIVES
DOZENS AND DOZENS OF BOOKS AND LOTS OF SOFTWARE.
BEST OFFER PLUS SHIPPING
DON'T BE BASHFUL, MAKE AN OFFER IF YOU WANT THIS STUFF. YOU MIGHT BE
SURPRISED.
bobm(a)istal.com
In a message dated 5/21/99 1:49:05 PM US Eastern Standard Time,
jim(a)calico.litterbox.com writes:
> Here's a thought.
>
> If you've got classic computers you'd love to run but can't think of
> anything
> to DO with them, (and they speak unix) go to
http://setiathome.ssi.berkeley.
> edu
> and make your computer's idle cycles part of the SETI search for
> extraterrestrial life. They download you a chunk of data from the Arecebo
> radio telescope and your computer spends its idle time running analysis on
> that chunk, then sends the results back.
I believe distributed.net has a similar premise where just about any computer
could help crack some encryption algorithm.
They had client software for many operating systems including my favourite,
OS/2. Even xt based machines could help out by running dos based client
software.
david
>How big (storage capacity) might this device provide.
512 kbytes for the RS03, 1024 kbytes for the RS04.
>As for a picture, I shall look into providing same to the newsgroup.
>I do not have a web page, so some other mechanism of image
>distribution will be required.
Doesn't everyone here have a mid-70's PDP11 Peripheral Handbook? They've
all got a picture of the RS series drives (and RM, and RP, and RK, and
RX, and ...)
--
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
> I picked up a Compupro 816 computer yesterday and an external drive unit
>with a hard drive and an 8" floppy drive. I haven't brought it home yet so
>I haven't taken more than a quick look at it. Can anyone tell be about the
>computer and drive? What CPU, speed, etc. What kind of operating system it
>uses, etc.
If it's using the same CPU's it shipped with, it has a 8085A and a
8088A on a 85/88 CPU board. Speed is 2 or 5 MHz, depending on what
the big red switch labeled "SPEED" on the CPU board is set at.
Of course, it's a S-100 box, so just about anything could have been
dropped in at either the factory (special-order), the Compupro dealer,
or by the end user.
Typically the system either ran CP/M-80, CP/M-86, or a special
Compupro version that was basically CP/M-86 but would also run 8-bit
executables on the 8085.
There were many aftermarket CPU's available, some with 80286's on them
and 8 MHz Z-80's, that were commonly dropped into Compupro chassis.
> I don't see a keyboard or video connectors so I assume it needs
>a terminal to talk to it.
Very likely, yes. Most likely, it has a System Support 1 board
with console serial port, clock, and interrupt controllers. But there
are lots of other ways to set up a S-100 system.
> Does any have a pinout of the serial port so I
>can make a terminal cable.
Look for a 25-pin cable from the System Support 1. It's plain old
RS-232. Depending on which OS and version you run, and how it was
generated, you might need to assert DTR.
> What size is the hard and floppy drives
You tell us :-). A Compupro 816 most likely shipped with a Qume
Datatrack DSDD 8" floppy drive, a bit over a Megabyte, most likely
hooked to a Disk 1 (or 1A or 1B or 1C) controller in the S-100 chassis.
The hard drive is likely a MFM drive, anywhere between 5 and 30 Megabytes,
hooked to a Disk 3. Again, just about anything was orderable/configurable.
> does
>the floppy drive use hard sectored disks, etc etc, etc.
Almost certainly soft-sectored disks.
> I noticed that
>there are connectors for both a 5.25" and an 8" floppy drives and another
>for a hard drive on the back of the CPU box. Does anyone have a manual or
>the OS software for one of these?
Sure. I bought out the last Canadian Compupro dealer while I was in
Vancouver and have manuals, configuration software, etc. Let us know
what's *in* your box and you'll get more details.
--
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
So interesting that you would suggest the results of "device
surgery," as that is one of the options that I had considered.
How big (storage capacity) might this device provide.
As for a picture, I shall look into providing same to the newsgroup.
I do not have a web page, so some other mechanism of image
distribution will be required.
William R. Buckley
>Well the RS11 with no suffix is just the controller but since yours has a
>motor and a "W" serial number it sounds like one of the fixed head disks
>for the RF11. I'm guessing that the tube would connect to the air
>filtration system. I've not had much luck locating a picture for
>comparison. I'll bet you any amount of money if you were to open it you
>would find a single platter attached to that motor inside the housing and a
>pair of read/write heads.
>--Chuck
>
Anyone know the name of the font used in the old "d|i|g|i|t|a|l" logo? I'm
trying to reconstruct it (I've found a couple of gif files but I'd really
like line art) for reproduction. Compaq is squashing this logo fast so
seeing it is getting harder and harder!
--Chuck
