[Reposted due to Enlow UCE cancel]: This Week With My Coleco ADAM 9710.20
Richard Drushel
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This Week With My Coleco ADAM 9710.20
by Richard F. Drushel (dru...@apk.net)
I. Status Report: SmartWriter Disassembly.
I'm happy to report that yesterday I finished my complete disassembly
and reverse-engineering to assemblable source code of SmartWriter R80. This
was done using Kenneth Gielow's Z80DIS 2.2 under the Z80MU CP/M emulator for
MS-DOS. The new source is formatted for the Z80ASM+ assembler from SLR. The
new source (minimally commented; it has all the EOS global symbols in it, as
well as a few things I added on my own) is available for anonymous ftp at:
ftp://junior.apk.net/pub/users/drushel/sw_r80.zip
This file is a PKZIP 2.04g compressed version of the ASCII plaintext source.
Note that it has no bugfixes or changes; it will exactly regenerate the
original SmartWriter R80 binary, warts and all. Of course, now this source
code can serve as the basis for bugfixes/upgrades to SmartWriter (including
making it XRAM-friendly for a possible XRAM-based EOS).
II. Verifying the New Source Code.
How can I be sure that I correctly reverse-engineered the source code?
The new SmartWriter source was verified in two ways:
(1) the new source was reassembled to a 32K binary image using Z80ASM+,
then compared byte-by-byte with the original binary image of the
R80 SmartWriter ROM. Except for padding out the unused ROM space
with 00H instead of 0FFH, my new binary was identical to the old.
(2) the new source was modified by inserting a NOP instruction after
the first instruction, reassembled to a binary image, then tested
using Marcel de Kogel's ADAM Emulator for MS-DOS, ADAMEM.EXE. The
effect of the NOP is to displace all the code forward by one byte,
without affecting the program operation (NOP means No OPeration,
it doesn't do anything). Extensive testing of the new binary
revealed no operational errors.
What is the rationale for (2)? In the code, there are many references
to ROM data areas (e.g., message strings, sprite patterns), which of course
are to the addresses in ROM at which those data sit. In a typical program,
executable code and non-executable data are intermingled in the binary image.
Since a disassembler program doesn't know anything about the internal structure
of the binary it's disassembling, data areas often appear as "garbage" machine
code instructions in the raw disassembly output. It is the task of the human
disassembler to recognize such "garbage" code and edit the listing to properly
mark it as data. Any data references which aren't caught, however, will no
longer point to the proper place if the code length changes in editing, and
the data doesn't end up in exactly the same place in ROM that it originally
occupied. Thus, inserting a NOP to shift the reading frame of the code, then
testing the new binary for errors, will reveal any missing data references as
program bugs.
The initial NOP-shifted binary did not boot at all--I got a black screen.
Clearly, I had missed some data references. I then started from the end of the
program and worked forward, inserting a NOP, reassembling, and then retesting.
NOPs inserted towards the end allowed the binary to boot, but the screen was a
bit scrambled. One bug at a time--track down what kept it from booting first,
and worry about the screen garbage later.
By repeated NOP-shifting, always bisecting the interval between what would
boot and what gave the black screen, I found the place in the code where I had
missed a data reference. In the code which loaded EOS from ROM to high RAM,
the start address of the ROM was listed as "program label 6000H" instead of
just the number 6000H. Any NOP inserted after 6000H wouldn't cause a problem,
but a NOP before 6000H would cause "program label 6000H" to have the *value*
6001H--which would cause the whole of EOS to be copied to the wrong location in
RAM, and thus crash as soon as any EOS function call was attempted. Fixing
this in the new source allowed SmartWriter to boot--but with a scrambled
screen, as noted above.
The scrambled-screen problems were due to references to a few video RAM
(VRAM) addresses which happened to have the same numeric value as some program
labels. (The disassembler just sees the final number, and if there is a
program label with that number, it substitutes that label name in the code.)
During my initial cleanup of the raw disassembly listing, I had recognized and
fixed a few of these anyway, from my familiarity with how VRAM is typically
used; but some others less obvious slipped through the cracks. Again, it was
repeated NOP-shifting (always bisecting the interval between a shift that
"broke" the program and one which had no effect) which allowed me to zero in
on the references to program labels which needed to be changed into numbers.
(The strategy is exactly like that in the "higher-lower" game, in which one
person thinks of a number, and a second person tries to guess it, the first
person answering only "higher" or "lower" depending upon the accuracy of the
guesses.)
When the screen was unscrambled, there remained a small glitch: in the
ADAM'S ELECTRONIC TYPEWRITER mode, the message string for SmartKey V was off
by a few letters if I NOP-shifted the code at the beginning. Using the same
procedure described above, I zeroed in on the offending part of the code, but
couldn't see what was causing the problem: the critical address was the very
address of the particular SmartKey V message string!
To make a long story short, the problem was that I had not correctly
separated code from data areas in the subroutine which draws the SmartKey
menus for the ELECTRONIC TYPEWRITER. In SmartWriter, SmartKey menus are
drawn using an economical yet uncongenial-to-disassembly subroutine which
includes the address of the string directly after the CALL to the menu-
drawing routine. Here's the critical bit of code, correctly resolved:
C.0B07:
CALL DRAW_YELLOW_SK_4
;
DW I$12FC
; -----------------
;
CALL DRAW_SK_5
;
DW I$132D
; -----------------
;
CALL DRAW_SK_6
;
DW I$131C
; -----------------
;
RET
;
; -----------------
;[...]
I$12FC:
DB ' ADAM''S ',0DH ;0DH is carriage return
DB ' ELECTRONIC TYPEWRITER',03H ;03H is ETX, end-of-text marker
I$131C:
DB ' MARGIN',0DH
DB ' RELEASE',03H
I$132D:
DB ' MARGIN/',0DH
DB 'TAB/ETC',03H
The subroutines of the form CALL DRAW_YELLOW_SK_x draw a yellow box from
SmartKey I to SmartKey x, with the text of string at the address following the
CALL printed in black. The subroutines of the form CALL DRAW_SK_x draw a blue
(2 possible shades, depending upon which SmartKey) box in SmartKey x's space,
with the text of the string at the address following the CALL printed in white.
The DW LABEL$ assembly directive means to store a Data Word containing the
address of the program label LABEL$, whatever value LABEL$ has at assembly
time.
The first time through the disassembler, however, all these "inline" data
references get treated as code. When I first recognized the existence of the
DRAW_YELLOW_SK_x and DRAW_SK_x family of functions, I searched through the
code listing and (supposedly) changed all the "garbage" code to DW references.
In the case of the 'MARGIN/TAB/ETC' string, however, I missed one; and the
(2DH, 13H) was treated as the following assembly code:
CALL DRAW_SK_5
;
DEC L ;2DH
INC DE ;13H
This meant that, when I NOP-shifted the program anywhere prior to I$132D, the
new value of this label was *not* updated in what should have been the data
reference after the CALL DRAW_SK_5. The result was that this DRAW_SK_5 would
*always* try to draw a SmartKey with whatever data it found at address 132DH,
even if the actual message string had shifted to a different absolute address.
Needless to say, putting in the correct reference as DW I$132D fixed the
problem; and now I could edit the new SmartWriter source at will, without
fear of such frameshift errors being introduced by the edits.
III. Code Fossil: ADAMlink Modem I/O in SmartWriter.
My first disassembly of SmartWriter was done in 1992 or thereabouts,
using the UNASMHEX disassembler I wrote for SmartBASIC 1.0 and 1.x (and ported
to Microsoft BASIC). This disassembler did not make any attempt to generate
assemblable source code; but I used it extensively, and it was my primary
tool for figuring out how to patch PowerPaint for hard drives, HARDDISK 2.3
and 3.9 for RAMdisks, and ADAMlink IValpha to make ADAMlink V (not to mention
SmartBASIC 1.0 itself to make SmartBASIC 1.x). I made a quick pass through
SmartWriter just for fun, I guess, and at that time had discovered a truly
amazing code fossil: SmartWriter knows about the ADAMlink modem, and tries
to talk to it at startup!
I believe that I wrote a brief report of this discovery for A.N.N., but
I can't be completely sure. At any rate, during the resourcing of SmartWriter,
I came across the code again; so here it is, with some brief explanations:
MODEM_CTRL_PORT EQU 5EH ;ADAMlink modem control port (2651 UART)
MODEM_DATA_PORT EQU 5FH ;ADAMlink modem data port (2651 UART)
; -----------------
;Load a program through ADAMlink modem!
;At least that's the intent. It can't work, however, because
;there is no handshaking for any of the data reads; a 300 bps
;modem can't supply the characters that fast. Maybe if the
;proper handshaking were added...it would be interesting.
C$103C:
LD BC,(D$1071)
LD A,B
OUT (C),A ;send first init command
LD BC,(D$1073)
LD A,B
OUT (C),A ;send second init command
LD A,(D$1075)
LD C,A ;get data port
IN A,(C) ;read for first magic number
CP 0AAH ;was it magic1?
JP NZ,J.1070 ;no, so exit
;
IN A,(C) ;yes, so read second magic number
CP 55H ;was it magic2?
JP NZ,J.1070 ;no, so exit
;
IN E,(C) ;yes, so get DE=count
IN D,(C)
IN L,(C) ;get HL=load address
IN H,(C)
PUSH HL ;save start vector
J$1065:
IN A,(C) ;read a byte
LD (HL),A ;save it
INC HL ;point to next address
DEC DE ;one less count
LD A,E
OR D ;is D=E=0?
JR NZ,J$1065 ;no, so keep going 'til done
;
POP HL ;yes, so restore load address
JP (HL) ;and jump to program start
;
; -----------------
J.1070:
RET ;exit
;
; -----------------
;initialization data for ADAMlink modem
D$1071:
DB MODEM_CTRL_PORT,00H ;port, data
D$1073:
DB MODEM_CTRL_PORT,80H ;port, data
D$1075:
DB MODEM_DATA_PORT ;port
; -----------------
As noted in the code comments, there's no way that this can work with
the ADAMlink modem as we now have it; there's no handshaking for any of the
modem data port reads. So, if you try to set this up now, with a second
computer ready to send a program at 300 bps, it will fail. Now that I have
reassemblable source for SmartWriter, though, it might be worth trying to make
this code workable, just for kicks.
Why is this routine in here, to load and run a file over the ADAMlink
modem? At this late date, only the SmartWriter programmers themselves could
answer definitively; but I will offer this intriguing speculation as food for
thought:
What if Coleco planned to start a nationwide BBS service, like CompuServe?
They would have support areas for the ColecoVision and the ADAM, news about
upcoming hardware and software, etc. Presumably the only way you could login
would be via an ADAMlink modem (there were no third-party ADAMlink modems or
serial interface boards to use standard Hayes-type modems). What if you wanted
to try out a demo version of some new ColecoVision game or ADAM program, while
you were on-line? In the appropriate forum, you could issue a command to
start downloading a program (after making sure that your ADAMlink boot tape or
disk was out of the drive), then pull the reset switch on your ADAM. Since
you're still on-line, and loader code in SmartWriter doesn't hang up the phone,
you could start receiving the file. This loader would grab the file, put it in
RAM at the appropriate place, then run it. Presumably, the demo program would
have a software escape mechanism to reboot the machine under ADAMlink so you
could continue your online session. And this would be "safe" for Coleco
because there would be no way for the users to save the program they had
downloaded, because it wasn't downloaded to disk or tape, but rather directly
to RAM, from which there is no escape (the ADAM not having a built-in debugger
or program tracer).
In many respects, the Coleco ADAM is to the 1980s what TV-based "network
computers" are to the 1990s. Technically, however, there is no way that 300
bps could have efficiently transmitted multimedia-type data. Even a 4K demo
program would take over 2 minutes to download at 300 bps 8N1. I predict that
"network computers" will be as commercially successful as the ADAM...
IV. Possible Repair of SmartWriter R80 Bugs.
Now that SmartWriter can be changed at the source level (meaning, repairs
are easy and can be as extensive as desired), you should all send me your lists
of long-standing bugs to fix. The one that I remember is the inability to
access disk 2 (drive D). I know where in the code the tape/disk detects are,
and it looks to be a straightforward fix to add support for disk 2. (I may
even start playing with this tonight, after my kids are in bed.) I also seem
to recall something to do with there being an extra linefeed or half-linefeed
at the bottom of pages during printing; if someone can send me a detailed
description of how to produce this bug, I'd be grateful).
From the PRINT menu, there is an unused SmartKey menu entry for PRINT
FILE. Making it print A-type (plain ASCII) files is trivial; making it
interpret an existing SmartWriter file without actually loading it in and
printing it from the workspace is probably a lot harder, but doable (I haven't
looked).
Also, it might be nice to have native support for the PIA2-type parallel
printer card (instead of having to run FASTPATCH or some equivalent). Again,
adding the driver code is easy--and I've even published the core parallel
printer driver in a previous TWWMCA. Of course, anything requiring specific
escape codes for parallel printers is out. A 132-column mode would probably
involve deciphering and documenting SmartWriter's RAM data tables above 8000H,
which I haven't done and wouldn't particularly relish doing.
It is also very easy to disable the XRAM detect routine, which would
prevent SmartWriter from recognizing XRAM at all, thus making it more friendly
to future XRAM-based operating system upgrades. If disk 2 support is being
added, it probably would be worth adding RAMdisk (device 26) support at the
EOS level (leaving it to the EOS RAMdisk driver to worry about how to manage
the different memory bank switches that would be necessary).
So, send me your bug lists for SmartWriter! There are more than 3751
bytes free at the end of the 32K ROM to play with, which is lots of space in
Z80 machine code!
See you next week!
*Rich*
***************************************************************************
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ftp://junior.apk.net/pub/users/drushel/twwmca/
Files have the form wkyymmdd.txt, where yy=year, mm=month, dd=day.
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Richard Drushel
Alfred Blanchard
Hi all,
Is there any general interest in NEW ST-506 (5 Meg) MFM hard drives?
I have found a source of some 200 drives. These are NOT used. In fact
they are still in their original shipping contianer. I was not quoted
any specific prices for these so I can't say how much the owner wants
for each. So I told him I would post a message to see if selling these
drives are worth the effort.
TIA,
A. J.
--
DSC Communications Corporation Internet:abla...@spd.dsccc.com
1000 Coit Road Plano, Texas 75075
** The opinions expressed are not those of DSC Communications, Inc **
Jeff Jonas
In article <344F6C...@spd.dsccc.com>
Alfred Blanchard <abla...@spd.dsccc.com> writes:
>Hi all,
>Is there any general interest in NEW ST-506 (5 Meg) MFM hard drives?
>I have found a source of some 200 drives. These are NOT used. In fact
>they are still in their original shipping contianer. I was not quoted
>any specific prices for these so I can't say how much the owner wants
>for each. So I told him I would post a message to see if selling these
>drives are worth the effort.
I wonder if they'll even spin up since heads stuck to the platters
after a lot of inactivity ("stictation").
I have a ST-506 drive that I'm keeping only for the historical curiousity
of having the drive that DEFINED the ST-506 MFM interface!
It uses a stepper motor to move the heads, just like a floppy drive,
thus the huge step timings! And the heads slide along tracks
instead of pivoting. It may be more entertaining to open some up
to show how old disks worked!
--
Jeffrey Jonas
jeffj@panix(dot)com
Meow? PRR PRR PRR !
Richard Ross
Alfred Blanchard <abla...@spd.dsccc.com> wrote:
>Hi all,
>
>Is there any general interest in NEW ST-506 (5 Meg) MFM hard drives?
>I have found a source of some 200 drives. These are NOT used. In fact
>they are still in their original shipping contianer. I was not quoted
>any specific prices for these so I can't say how much the owner wants
>for each. So I told him I would post a message to see if selling these
>drives are worth the effort.
If they are in the original boxes/packing, I'm interested. Tell me
more...
(I'm a sucker for antiques! Just think, in our accelerated field of
interest, unlike old car enthusiasts, we only have to wait 10-15 years
for our equipment to reach Model T status!)
Thanks,
Rich
PC Medix
Eric Chomko
: Is there any general interest in NEW ST-506 (5 Meg) MFM hard drives?
: I have found a source of some 200 drives. These are NOT used. In fact
: they are still in their original shipping contianer. I was not quoted
: any specific prices for these so I can't say how much the owner wants
: for each. So I told him I would post a message to see if selling these
: drives are worth the effort.
I'm in at a buck a piece. We'll split shipping. :)
Eric
: TIA,
John Foust
On Fri, 24 Oct 1997 21:24:21 GMT, pcm...@pipeline.com (Richard Ross)
wrote:
>
>Alfred Blanchard <abla...@spd.dsccc.com> wrote:
>>
>>Is there any general interest in NEW ST-506 (5 Meg) MFM hard drives?
>>I have found a source of some 200 drives. These are NOT used. In fact
>>they are still in their original shipping contianer.
They might be worth the cost of shipping them... :-)
- John
g...@immortal.org
Alfred Blanchard wrote:
> Is there any general interest in NEW ST-506 (5 Meg) MFM hard drives?
> I have found a source of some 200 drives. These are NOT used. In fact
> they are still in their original shipping contianer. I was not quoted
> any specific prices for these so I can't say how much the owner wants
> for each. So I told him I would post a message to see if selling these
> drives are worth the effort.
Whoa! Amazing... Well, it would be nice if they could be setup in one
big RAID. But alas, they couldn't be. A figure of $1/MB seems too
expensive these days.
How about pricing each units in regard to its carton's condition. Best
ones fetch $10. A well but not-that-prestine goes for $5. All others
go at $2 a piece? I bet the S/H would cost more than those!
Layton Davis
Alfred Blanchard wrote:
>
> Hi all,
>
> Is there any general interest in NEW ST-506 (5 Meg) MFM hard drives?
> I have found a source of some 200 drives. These are NOT used. In fact
> they are still in their original shipping contianer. I was not quoted
> any specific prices for these so I can't say how much the owner wants
> for each. So I told him I would post a message to see if selling these
> drives are worth the effort.
>
>
> A. J.
> --
> DSC Communications Corporation Internet:abla...@spd.dsccc.com
> 1000 Coit Road Plano, Texas 75075
> ** The opinions expressed are not those of DSC Communications, Inc **
I would be interested if anyone knew where I could find a hard drive
controler for a TRS-80 Model 4P. Of course, I only keep it for
sentimental reasons, but a hard drive for it would still be nice - if it
didn't cost too much.
I can be reached at lay...@usa.net
William Hunt
je...@panix.com (Jeff Jonas) writes:
> Alfred Blanchard <abla...@spd.dsccc.com> writes:
>>Hi all,
>>Is there any general interest in NEW ST-506 (5 Meg) MFM hard drives?
>>I have found a source of some 200 drives. These are NOT used. In fact
>>they are still in their original shipping contianer. I was not quoted
>>any specific prices for these so I can't say how much the owner wants
>>for each. So I told him I would post a message to see if selling these
>>drives are worth the effort.
>I wonder if they'll even spin up since heads stuck to the platters
>after a lot of inactivity ("stictation").
>I have a ST-506 drive that I'm keeping only for the historical curiousity
>of having the drive that DEFINED the ST-506 MFM interface!
>It uses a stepper motor to move the heads, just like a floppy drive,
>thus the huge step timings! And the heads slide along tracks
>instead of pivoting. It may be more entertaining to open some up
>to show how old disks worked!
I've got some old Shugart SA4008 drives circa 1979 - big 14"
monsters - which talk MFM.
Now these are really perverse units. Inside the suit-case
size cabinet is mounted an MFM to GPIB interface, and the host
computer (an 8085 based oddball machine) talks to them via the
GPIB. No other GPIB peripherals supported, just the disks.
The MFM/GPIB board claims to support ST-506 drives but I've
never tried it.
There must be 50 pounds of aluminum in the chassis casting alone.
You can see the platters spin inside the clear plastic bubble.
The spindle is spun by an externally mounted motor the size of a
washing-machine motor :*) through a rubber belt. When you turn
them on, the lights dim until they come up to speed. Then there
is a big rattle of relays before the ready light comes on. They
produce a wonderful whoosh hum and rumble just like the old
mainframes. I feel like I should be wearing a lab coat when I
run these things. All 8 heads ride a single pivoted 'actuator'
arm. The arm is positioned by a 'capstan' stepper motor and band,
one step per track.
Twin platters turn at 2964 RPM. 7.1Mbit/sec transfer rate,
(before the GPIBC), 20msec track to track, 65msec average seek.
8 heads, 60 cylinders, 202 tracks. Unformatted 29 Mbytes,
formatted 24Mbytes. By 1981, the retail price had fallen to
only $12,500. By 1983 they were obsolete, replaced with 5-1/4"
units.
Worst part is, I've got two of these actually still in use here,
but not daily. I had a client who did use one 8hrs per day,
5days a week until early 1996. Very reliable. Wellll beyond
the advertised 5000 hour life expectancy. Only took it down
because the client passed away. That drive should have received
an award for longest continual use of obsolete storage hardware
in history.
--
William Hunt, Portland Oregon USA w...@teleport.com
bill_h
William Hunt wrote:
>
> I've got some old Shugart SA4008 drives circa 1979 - big 14"
> By 1983 they were obsolete, replaced with 5-1/4" units.....more snipping....
> I had a client who did use one.........(snip).... Only took
> it down because the client passed away.......
> ......that drive should have received an award for longest
> continual use of obsolete storage hardware in history.
taking your last point first......well, there's that little matter of
some stone jars in caves around Qumron that preserved some rather
interesting scrolls for, oh, maybe 18 or 19 centuries......
I don't think too many people using 'personal' computers would have
used 14" hard drives, but a fair number DID use the 8" version of the
monsters you described. Also with the clear case over the platters, you
can even watch them run. And with slightly smaller moters, relays, and
housing, you can even lift the 8" ones.
Anybody know if the Altos is a fair candidate for
"first personal computer to come with built-in hard drive"?
Tony Duell
bill_h (bil...@azstarnet.com) wrote:
: William Hunt wrote:
: >
: > I've got some old Shugart SA4008 drives circa 1979 - big 14"
: > monsters - which talk MFM.....bunch of stuff about how they work snipped......
: I don't think too many people using 'personal' computers would have
: used 14" hard drives, but a fair number DID use the 8" version of the
I'm pretty sure my PERQ 1 workstation has a 14" Shugart SA4000-series drive
in it (somebody who knows the PERQ hardware better than me can correct me),
and that machine was sold as a 'personal graphics workstation'.
It's an interesting drive. It is liftable - just - and parking the heads
to move the machine (which you'd better do if you want it to work at the
other end) involves removing the casing, powering up the machine, putting
a locking clip into the stepper motor (with the drive turning), powering
down, and putting a locking screw into the spidle pulley.
: monsters you described. Also with the clear case over the platters, you
: can even watch them run. And with slightly smaller moters, relays, and
: housing, you can even lift the 8" ones.
Alas the 8" hard disks that I'm familiar with are the Micropolis 1200's that
are used in PERQ2T1's. Those are in a solid metal case and there's not a lot
to see. There is one curious feature, though (other than the diagnostic
interface port) and that is a car tyre-like valve on the top of the HDA. I
have no idea what it's for, and the service manual doesn't mention it.
-tony
R. D. Davis
In article <EIq3...@fsa.bris.ac.uk>, Tony Duell <a...@siva.bris.ac.uk> wrote:
>bill_h (bil...@azstarnet.com) wrote:
>: William Hunt wrote:
>: >
>: > I've got some old Shugart SA4008 drives circa 1979 - big 14"
>: > monsters - which talk MFM.....bunch of stuff about how they work
>: > snipped......
Any chance that any of these are for sale? Having a spare or two, in the
event of a head-crash, on hand could be useful.
>: I don't think too many people using 'personal' computers would have
>: used 14" hard drives, but a fair number DID use the 8" version of the
Why not? I use them in my PERQ-1 graphics workstations, which are
personal computers... says so right in the front of the OS manual. :-)
I've also heard of people using them with their CP/M systems.
>I'm pretty sure my PERQ 1 workstation has a 14" Shugart SA4000-series drive
>in it (somebody who knows the PERQ hardware better than me can correct me),
>and that machine was sold as a 'personal graphics workstation'.
Yes, you're right, it does have an SA4000 series drive; an SA4004 is
what's in mine, if I recall correctly.
>Alas the 8" hard disks that I'm familiar with are the Micropolis 1200's that
>are used in PERQ2T1's. Those are in a solid metal case and there's not a lot
>to see. There is one curious feature, though (other than the diagnostic
>interface port) and that is a car tyre-like valve on the top of the HDA. I
>have no idea what it's for, and the service manual doesn't mention it.
I can't gurantee that this is the correct answer (a guess is more like
it), but I suspect it has something to do with the air pressure inside
the drive. Recall that other hard drives, such as the SA4004 and
Vertex V150 have some sort of filter/air pressure regulation devices
in them. It's my guess that this drive needs to have well filtered
air added to it, or removed, depending upon where its used (e.g. - if
it's used very high up in the mountains, for example).
--
R.D. Davis http://www.access.digex.net/~rdd
r...@access.digex.net Computer preservationist. Many types of
...!uunet!mystica!rdd unwanted older computer systems disassembled,
Office telephone: 1-410-744-4900 removed for free (locally) and preserved.
Tony Duell
R. D. Davis (r...@access4.digex.net) wrote:
: >Alas the 8" hard disks that I'm familiar with are the Micropolis 1200's that
: >are used in PERQ2T1's. Those are in a solid metal case and there's not a lot
: >to see. There is one curious feature, though (other than the diagnostic
: >interface port) and that is a car tyre-like valve on the top of the HDA. I
: >have no idea what it's for, and the service manual doesn't mention it.
: I can't gurantee that this is the correct answer (a guess is more like
: it), but I suspect it has something to do with the air pressure inside
: the drive. Recall that other hard drives, such as the SA4004 and
: Vertex V150 have some sort of filter/air pressure regulation devices
: in them. It's my guess that this drive needs to have well filtered
: air added to it, or removed, depending upon where its used (e.g. - if
: it's used very high up in the mountains, for example).
Hmmm... The Micropolis 1200 has such a filter as well - it's on the top of
the HDA (back when fitted into the PERQ). The valve I mentioned is _just_
like a car tyre valve, and would let air into the HDA only. There is also
a metal cap (and rubber seal) that's screwed over the valve when the
drive is assembled, so I doubt very much goes in or out through it.
It looks like it was used for something at the factory. Alas I don't have any
dead 1200's or I'd strip one to see if there's anything on the inside. The
service manual doesn't mention this feature at all.
-tony
john r pierce
bill_h <bil...@azstarnet.com> wrote:
>I don't think too many people using 'personal' computers would have
>used 14" hard drives, but a fair number DID use the 8" version of the
The first Altos HD systems I recall used exactly these Shugart 400x series
drives. I also recall Compupro/Godbout S-100 systems that could use either the
14" 400x or a Fujitsu(?) 8" that was around 20 or 30MB.
Far as I know, the very first hard disk CP/M system was a kludged up Pertec 14"
5MB fixed / 5MB removable with a external rack mount controller/formatter (based
on a Signetics 8X300 microcontroller) which was interfaced to a Multibus
wirewrap board plugged into an Intel MDS-800 system at Digital Research. This
was brought up with CP/M 1.4 by partitioning the 5MB+5MB into 10 total
partitions of 1MB each and using a 'map' command to map the 4 possible 'floppy'
drives to any combination of floppy A/B/C/D or hard disk 0/1/2/3/4/5/6/7/8/9.
This was early 1978 when 1.4 was still in development.
>Anybody know if the Altos is a fair candidate for
> "first personal computer to come with built-in hard drive"?
If I remember right, the Altos 14" hard drives were in a seperate wood grained
chassis that sat under system unit with the bank select Z80 and dual SA-800 FD
drives. Digital Systems also had a similar system at about the same time.
-jrp
----------------------------------------------------------------------
This posting has a invalid email address to discourage bulk emailers
Due to the ever increasing volumes of spam, I do not mix mail and news
----------------------------------------------------------------------
Dave Baldwin
Jeff Jonas wrote:
>> ALL the memory was on a rotating disk that was used like a drum:
> fixed heads one per track.
As late as 1985, a company named Vermont Research was making 10 Megabyte
Drum memories and I really wanted one though I couldn't possibly afford
it.
Why? With a head per track, it had a MAXIMUM of 8.3 mS access time which
was one revolution of the drum. Essentially 0 seek time since all you
did was switch heads, not move them.
--
- -=-=-=-=-=-=-=-=-=-=- The Computer Journal -=-=-=-=-=-=-=-=-=-=-=-
Dave Baldwin, Editor/Publisher | (800) 424-8825 or (916) 722-4970
Email: t...@psyber.com | Small scale computing since 1983
Hands-on hardware and software | Support for older systems
BBS: (916) 722-5799 | FAX: (916) 722-7480
- -=-=-=-=-=-=- Home page "http://www.psyber.com/~tcj/" -=-=-=-=-=-=-
Eugene A. Pallat
bill_h <bil...@azstarnet.com> wrote in article
<3454DF...@azstarnet.com>...
> William Hunt wrote:
> >
> > I've got some old Shugart SA4008 drives circa 1979 - big 14"
> > monsters - which talk MFM.....bunch of stuff about how they
work snipped......
snipping....
> I don't think too many people using 'personal' computers would have
> used 14" hard drives, but a fair number DID use the 8" version of the
> monsters you described.
How about a fixed head drive system with 1 head per track. With 2 vertical
disk platters 3 feet in diameter (I'm not kidding) and 4 surfaces, I think
I had around 40 mb. We called it a "turkey disk" due to its size. The
cabinet was about 2 feet deep, 4 feet high, and about 5 feet long.
snip
> Anybody know if the Altos is a fair candidate for
> "first personal computer to come with built-in hard drive"?
>
Remove the '-glop-' for sending email to me.
Gene eapa...@orion-glop-data.com
Orion Data Systems
Solicitations to me must be pre-approved in writing
by me after soliciitor pays $1,000 US per incident.
Solicitations sent to me are proof you accept this
notice and will send a certified check forthwith.
Robert Billing
> to see. There is one curious feature, though (other than the diagnostic
> interface port) and that is a car tyre-like valve on the top of the HDA. I
> have no idea what it's for, and the service manual doesn't mention it.
I've seen this before on hardware which has to be transported by air
and has a sealed case. It allows a limited amount of pressure relief to
avoid excessive stress on the case, without admitting too much dust.
--
I am Robert Billing, Christian, inventor, traveller, cook and animal
lover, I live near 0:46W 51:22N. http://www.tnglwood.demon.co.uk/
"Bother," said Pooh, "Eeyore, ready two photon torpedoes and lock
phasers on the Heffalump, Piglet, meet me in transporter room three"
Tony Duell
Eugene A. Pallat (eapa...@orion-data.com) wrote:
: How about a fixed head drive system with 1 head per track. With 2 vertical
Talking of fixed-head drives...
What about a 14" fixed-head drive that's _not_ used to store digital data?
I have one. It was made by PPL (Process Peripherals Limited, I think), and
rotates at exactly 3000rpm. It stores 1 field of _analogue_ video on 3 tracks
(one for each of R,G,B) and replays it to the monitor.
I also have a rack of cards to link it to a PDP11 so that graphics data
can be recorded on it. This rack links to a DR11-B DMA interface, takes
in data, converts it to analogue (there's a hybrid DAC module on one of the
cards) and records it on the disk.
I am told that similar disks, but with analogue video inputs, were used for
TV action replays at one time.
-tony
Jeff Jonas
>How about a fixed head drive system with 1 head per track. With 2 vertical
>I had around 40 mb. We called it a "turkey disk" due to its size. The
>cabinet was about 2 feet deep, 4 feet high, and about 5 feet long.
For a young kid, I used some really old equipment since I tended to
find them in the back of the storage room at school and use 'em
since nobody else cared.
That's how I got to play with a General Precision LGP-21.
It had no core memory - but lotsa little metal cans (transistors).
Since it used an oscilloscope for the front panel display,
I guess it was a serial machine!
ALL the memory was on a rotating disk that was used like a drum:
fixed heads one per track.
Except the outer track which had many heads to keep
re-reading the accumulator, accumulator extension
and instruction counter.
Yup - recirculating memory a-la delay lines!
We were too poor to afford real registers!
Robert Billing
> I am told that similar disks, but with analogue video inputs, were used for
> TV action replays at one time.
Yes, Ampex made one.
There was also a gadget called an Emidicta, made by EMI, which recorded
voice (it was meant as a dictation machine) on flexible plasic disks
about a foot across. The disks could be folded if they had to be
posted, and then flattened out to be transcribed later by an audio
typist.
IIRC is was supposed to be used by travelling salesmen and the like to
dictate documents when away from base, and was supposed to be portable.
The machine is the size of a small suitcase and requires two HT
batteries to run a valve amplifier, two D cells for the filaments and
solonoid brake on the spindle, and frantic winding on a handle to get
energy into the clock spring that drives the spindle.
I think my machine is in the loft here somewhere, and it was in
working order when I last saw it.
I sometimes wonder if the Emidicta isn't the real ancestor of the
floppy.
Mike Morris
In article <3456E66D...@psyber.com> Dave Baldwin <t...@psyber.com> writes:
>From: Dave Baldwin <t...@psyber.com>
>Subject: Re: Q: Interest in: hard drives, history, et al
>Date: Tue, 28 Oct 1997 23:31:57 -0800
>Jeff Jonas wrote:
>>> ALL the memory was on a rotating disk that was used like a drum:
>> fixed heads one per track.
>As late as 1985, a company named Vermont Research was making 10 Megabyte
>Drum memories and I really wanted one though I couldn't possibly afford
>it.
>Why? With a head per track, it had a MAXIMUM of 8.3 mS access time which
>was one revolution of the drum. Essentially 0 seek time since all you
>did was switch heads, not move them.
>--
>- -=-=-=-=-=-=-=-=-=-=- The Computer Journal -=-=-=-=-=-=-=-=-=-=-=-
>Dave Baldwin, Editor/Publisher | (800) 424-8825 or (916) 722-4970
>Email: t...@psyber.com | Small scale computing since 1983
>Hands-on hardware and software | Support for older systems
>BBS: (916) 722-5799 | FAX: (916) 722-7480
>- -=-=-=-=-=-=- Home page "http://www.psyber.com/~tcj/" -=-=-=-=-=-=-
I was working at Jet Propulsion Labs in the 1974-1978 timeframe and
we had an EMR-6050 computer that had TWO of those drums, but in the
40 meg flavor. The drum cabinets were side by side and the JPL
crew had made a custom mod to the controllers - the system could write
to one or both. The system was used to simulate data steams from
the satellites for testing of the analysis software that ran on the
360/75s. Anyway, each bird generated different data streams, and
occasionally the simulation software crashed and it took too long
to reload the data from 800bpi tape. So when a second drum became
available it was snatched up and the system modified so a given
configuration could be written to both drums, and then the dual
write turned back off. Then later on if the code on drum A got
scrambled they could switch to B and reboot. THena simple copy
of the files to themselves would refresh the scrambled drum.
And Novell thought that they invented duplexing...
---------------------------------------------------------------------------
Mike Morris ham radio: WA6ILQ ICBM: 34:07:54.9 by 118:03:46.2
The above is my own opinion and should not be construed to be that of any of
my former or my current employers. The reply address is spoofed to discourage
junk email, please remove the "NOSPAM" from the address.
Tony Duell
Robert Billing (uncl...@tnglwood.demon.co.uk) wrote:
: There was also a gadget called an Emidicta, made by EMI, which recorded
: voice (it was meant as a dictation machine) on flexible plasic disks
: about a foot across. The disks could be folded if they had to be
: posted, and then flattened out to be transcribed later by an audio
: typist.
Interesting. I have a similar thing made by Olympia. It uses either
rigid or flexible plastic disks about 7" in diameter, magnetic oxide coated
with a groove in them. The latter guides the recoding head, which is mounted
on a pivoted arm like a record player.
There is a 2-valve mains-operated amplifier. There's also a motor/pulley/
solenoid arrangement to rotate the turntable and disk. It's all remote
controlled from a 4-position switch on the microphone (off, record, play,
rewind), and I believe there's a 2 pedal footswitch (play, rewind) to
be used when typing a transcription of the recording.
One odd feature is a button that puts the machine into high-speed rewind
and lowers a magnet onto the disk. It's used for bulk-erasing a disk, of
course.
: I am Robert Billing, Christian, inventor, traveller, cook and animal
-tony
Dr Pepper
In the early days, the hard drives were pressurized with dry nitrogen.
You want a positive pressure INSIDE the HD case, so that dust
particles can't get INSIDE due to higher pressure there than the
outside ambient pressure. It was only about 5 lbs or so.
==================================================
On Tue, 28 Oct 97 07:22:22 GMT, Robert Billing
<uncl...@tnglwood.demon.co.uk> wrote:
>In article <EIq3...@fsa.bris.ac.uk> a...@siva.bris.ac.uk "Tony Duell" writes:
>
>> to see. There is one curious feature, though (other than the diagnostic
>> interface port) and that is a car tyre-like valve on the top of the HDA. I
>> have no idea what it's for, and the service manual doesn't mention it.
>
> I've seen this before on hardware which has to be transported by air
>and has a sealed case. It allows a limited amount of pressure relief to
>avoid excessive stress on the case, without admitting too much dust.
>
>--
>I am Robert Billing, Christian, inventor, traveller, cook and animal
Edward Rice
In article <morris.155...@NOSPAMcogent.net>,
mor...@NOSPAMcogent.net (Mike Morris) wrote:
> When I worked at JPL in the 1974 to 1978 timeframe we had a pair of
> CDC 3100s that ran a forest of those disks ...
Was it a pair of CDC 3100's, which would have been seriously obsolete by
then, or perhaps a pair of the 3150's, which were actually slowed-down
3300's, and would have been just about current gear at that time? (The
3300 was a slower but more reliable version of the 3500, and none of the
3000L machines (3500 and lower numbers) was quite the same as the 3000U
(higher numbered) systems, either.
Jordin Kare
> Robert Billing (uncl...@tnglwood.demon.co.uk) wrote:
> : There was also a gadget called an Emidicta, made by EMI, which recorded
> : voice (it was meant as a dictation machine) on flexible plasic disks
> : about a foot across. The disks could be folded if they had to be
> : posted, and then flattened out to be transcribed later by an audio
> : typist.
>
> Interesting. I have a similar thing made by Olympia. It uses either
> rigid or flexible plastic disks about 7" in diameter, magnetic oxide coated
> with a groove in them. The latter guides the recoding head, which is mounted
> on a pivoted arm like a record player.
>
Around 1972, a friend picked up a surplus IBM "word processor"
(I don't think the term existed yet) based on a Selectric
mechanism and dating from the early Sixties. It had the
ability to store blocks of text or complete documents, print
them out, and do some crude editing, as I recall.
It used the strangest storage system I think I've ever seen
(and I've seen some strange ones):
*sprocketed* magnetic tape, stored on a single-reel cartridge, and read
*transversely*. Yes, the tape had sprocket holes a la 16 mm movie film.
The cartridge was about 4" square. When you inserted it, the tape end would
automatically be pulled out. As the tape unreeled, it didn't go onto
another reel; instead, it was dumped into a large bin one tape width wide,
where it would pile up in "lazy 8" loops until time to rewind it.
The read head was especially cute. The tape would advance one character
(one sprocket hole), and then the head, mounted on a solenoid, would shoot
sideways across the stationary tape, reading or writing the character.
The whole thing was entirely relay circuitry, except for the read and
write amplifiers for the heads, which may even have been tubes (memory
is hazy...).
Ah, for the good old days,
when Men were Men and Transistors were Germanium :-)
Jordin Kare
john r pierce
a...@siva.bris.ac.uk (Tony Duell) wrote:
>I am told that similar disks, but with analogue video inputs, were used for
>TV action replays at one time.
Analog magnetic video disks and/or drums, yes. On many of these, the head
actuator was manual for slow motion replay...
Mike Morris
In article <34585b64....@news.scruz.net> anti...@here.not (john r
pierce) writes:>From: anti...@here.not (john r pierce)
>Subject: Re: Q: Interest in: hard drives, history, et al
When I worked at JPL in the 1974 to 1978 timeframe we had a pair of
CDC 3100s that ran a forest of those disks - I forget if they were
Datum brand or Ampex. I also don't remember how many video channels
were generated by each disk unit - but the disks had a fixed head
for each channel, and a moving head to write new data on the disk
to update the channels. THe manufacturer had his rep on site on a
half time schedule (20 hours per week) to keep the video disks
running, and the on-site tech crew (of which I was one) knew enough
to swap a disk box for a good spare. This wasn't including the
weekly visit by the CDC CE, who was also on call for got-to-have-
the-spare-back-up-right-now situations, or for midcourse manuevers
when he was on lab for the entire period.
The CDCs received data from the IBM 360/75s and other sources and
created over 100 video channels of data display - each channel was
16 lines of 64 columns which were distributed around the scientific
community.
Some creative programming allowed the system to to graphics-
the software in the CDC would have to turn on a pixel in a
character cell, then write that character to the video disk.
But the hardware wrote 5x7 characters on a 7x9 grid - there
were 2 pixels betweenrows and columns. So you had to
mentally interpolate in that space. The CPU load graphic
made that the most visible... itlooked like you were looking
at a graph thoutgh a multi-paned window... And the CDCs
had about 32k of memory. Not meg - K. Everything was
done in assembler.
Certain video channels were dedicated to certain things - for
example three had the current CPU load of 360/75-A, B, and C.
Other channels monitored the Univac 1108-A and B. Other
channels were assigned as needed - the spacecraft power buss
or the navigation information went to almost every experiment
team, but the data that was on interest to only one team
generally didn't go anywhere else. Some experiments piggy
backed on others - there was a team that analyzed the
characteristics of the radio signal itself as teh spacecraft
looped behind a planet to see if that planet had a magnetic
field.
The screen with general spacecraft data went everywhere -
even the hanging-from-the-ceilings-monitors in the cafeteria.
The most-looked-at number was the OWLT - "One way light time",
which for Voyager got to over 2 hours. That was how long it
took radio signals (i.e. data, commands, etc.) to get back
from the spacecraft. You'd double that in your mind for a
command response time. Or as one scientist put it bluntly,
"If our bird gets hit by a rock, that's how long it will take
us to know." Or to put it another way - 4 hours for a ping.
It still amazes me what we did 20 years ago. And that the
spacecraft transmitter put out less power than a common
desk light bulb.
Mike
Don Maslin
anborg (anb...@eagle.seed.net.tw) wrote:
: There were other variations on that same theme. In the United States,
: General Electric made a childs toy magnetic recorder. It had a
: phonograph turntable (10 inch IIRC) with a drive pin. The recording
: media was a disk of essentially the same material as tape recording tape
: which was the same diameter. You placed the magnetic disk on the
: turntable with the magnetic side up and then on the center pin of the
: turntable, you placed a plastic hub which had a spiral groove molded in
: it. The recording/playback head was located at the end of the 'tone arm'
: which had a 90 degree bend in it. At the corner of the bend there was a
: pin which engaged the plastic disk and caused the head to wind over the
: magnetic disk as the turntable turned. IIRC the pin at the elbow was
: eccentric and a knob at the top of the arm allowed it to be turned so
: that the tracking of the head on the disk could be changed. This machine
: also had two or three tubes (valves) for the record/playback amplifier.
: I should still have the service literature for this device somewhere in
: storage.
: I have a vague memory that Brush Development Corp. made a dictation
: machine on roughly the same plan.
: Best regards,
: Art Borg
Sam Laur
In article <EItr9...@fsa.bris.ac.uk>, Tony Duell <a...@siva.bris.ac.uk> wrote:
>Interesting. I have a similar thing made by Olympia. It uses either
>rigid or flexible plastic disks about 7" in diameter, magnetic oxide coated
>with a groove in them. The latter guides the recoding head, which is mounted
>on a pivoted arm like a record player.
Sounds familiar. I have a dictation machine made by Assmann (gee, what a name!)
and it uses rigid magnetic-oxide coated disks, closer to LP size (12"). And
they also have a spiral groove on them.
--
/* Sam Laur sl...@utu.fi */
/* Carpe noctem! Carpe tenebras! */
Joseph Samson
>Analog magnetic video disks and/or drums, yes. On many of these, the >head
>actuator was manual for slow motion replay...
>
>-jrp
I used a few of these in the early '80's, one from Panasonic (a hard
disk) and one from Eigen (a 12 or 14 inch Bernoulli floppy). The
Eigen disks were used in horse race tracks to record finishes.
---
Joe
anborg
>
> Robert Billing (uncl...@tnglwood.demon.co.uk) wrote:
><snip>
> rigid or flexible plastic disks about 7" in diameter, magnetic oxide coated
> with a groove in them. The latter guides the recoding head, which is mounted
> on a pivoted arm like a record player.
>
> solenoid arrangement to rotate the turntable and disk. It's all remote
> controlled from a 4-position switch on the microphone (off, record, play,
> rewind), and I believe there's a 2 pedal footswitch (play, rewind) to
> be used when typing a transcription of the recording.
>
> One odd feature is a button that puts the machine into high-speed rewind
> and lowers a magnet onto the disk. It's used for bulk-erasing a disk, of
> course.
>
> : I am Robert Billing, Christian, inventor, traveller, cook and animal
Joseph Samson
anti...@here.not (john r pierce) wrote:
>Far as I know, the very first hard disk CP/M system was a kludged up >Pertec 14"
>5MB fixed / 5MB removable with a external rack mount controller
>formatter (based on a Signetics 8X300 microcontroller)
This is the same configuration that was sold with the Altair in the
late 1970's, probably after MITS was bought by Pertec. The computer and
disk were mounted in a desk enclosure made by Optima.
---
Joe
john r pierce
Joseph Samson <sam...@erim.org> wrote:
Scientific Atlanta / Optima, if I recall.
We never did get the desk from them, I don't think. or wait, maybe we did??
If that Pertec/Altair configuration was running CP/M it may very well have been
using my BIOS drivers.... Pertec had given us the drive and controller
specifically for development purposes...
I do seem to recall finally getting a S100 interface card for the Pertec
formatter/controller and moving the whole thing onto a S100 system (TEI? Imsai?
I forget). DRI never had any Altair hardware, it was just too flakey for us.
Robert Billing
In article <kare-29109...@ppp-astk04--166.sirius.net>
ka...@sirius.com "Jordin Kare" writes:
> *sprocketed* magnetic tape, stored on a single-reel cartridge, and read
> *transversely*. Yes, the tape had sprocket holes a la 16 mm movie film.
The Elliot 803 used something similar called "magnetic film".
> Ah, for the good old days,
> when Men were Men and Transistors were Germanium :-)
...and small furry creatures from Alpha Centauri were /real/ small
furry creatures from Alpha Centauri.
--
I am Robert Billing, Christian, inventor, traveller, cook and animal
Edward Rice
In article <kare-29109...@ppp-astk04--166.sirius.net>,
ka...@sirius.com (Jordin Kare) wrote:
> Around 1972, a friend picked up a surplus IBM "word processor"
> (I don't think the term existed yet) based on a Selectric
> mechanism and dating from the early Sixties...
>
> It used the strangest storage system I think I've ever seen
> (and I've seen some strange ones):
> *sprocketed* magnetic tape...
Unless I'm a generation off, it was an "MTST" -- a Magnetic Tape Selectric
Typewriter. Very cool, for its day. I never actually saw one, but I heard
a lot about them.
The MTST, if that is what you had, was supplanted by the "MCST," or
Magnetic Card Selectric Typewriter, and I had some experience with them.
It was a much less kludgy device, it sounds like.
Your mention of the tape being "dumped into a large bin one tape width
wide, where it would pile up in 'lazy 8' loops until time to rewind it"
reminds me of a really weird store-and-forward storage device I saw. It
was intended to store accumulated data until some triggering event
occurred, then forward it all at once, then wait to accumulate more data.
An example might be data monitoring until the storage device itself became
full, then sending of the data to another site by phone line, following by
more off-line accumulation.
This thing was on view at one of the Joint Computer Conferences in 1969 or
so, and it looked like a coffee table, complete with a glass top. The tape
was not on a reel, as we'd presume today, but was loosely and randomly
arrayed, one edge down and one edge up, between the glass top and the
internal base of the unit. The write head would pull tape in and pass it
back into the snake's nest of loose tape, and when the trigger event
occurred the read head would then "catch up" with the write head. It was
easily the neatest-looking device in the whole show, or maybe the whole
world, at that time.
Carl R. Friend
Howard S Shubs, in article
nr. <hshubs-0311...@ip68.dallas6.tx.pub-ip.psi.net> wrote:
>
> A disk drive that outlasts a human?
> Soon enough I bet we have storage devices which will do this for
> real (birth to death of the human).
But we already do.... Of course some of them start suffering bit-
rot after being operational for a few score or so.
--
______________________________________________________________________
| | |
| Carl Richard Friend (UNIX Sysadmin) | West Boylston |
| Minicomputer Collector / Enthusiast | Massachusetts, USA |
| mailto:carl....@stoneweb.com | |
| http://www.ultranet.com/~engelbrt/carl/museum | ICBM: N42:22 W71:47 |
|________________________________________________|_____________________|
Howard S Shubs
In article <62rn6i$f...@nnrp1.farm.idt.net>, Eric Chomko <cho...@IDT.NET> wrote:
>In alt.folklore.computers Alfred Blanchard <abla...@spd.dsccc.com> wrote:
>: Hi all,
>
>: Is there any general interest in NEW ST-506 (5 Meg) MFM hard drives?
>: I have found a source of some 200 drives. These are NOT used. In fact
>: they are still in their original shipping contianer. I was not quoted
>: any specific prices for these so I can't say how much the owner wants
>: for each. So I told him I would post a message to see if selling these
>: drives are worth the effort.
>
>
>I'm in at a buck a piece. We'll split shipping. :)
I'll take one at that price too.
--
Howard S Shubs hsh...@bix.com
The Denim Adept hsh...@mindspring.com
Howard S Shubs
In article <631cvu$sgr$1...@usertest.teleport.com>, w...@usertest.teleport.com
(William Hunt) wrote:
>Only took it down because the client passed away.
Like that's a reason. <grin>
A disk drive that outlasts a human? Soon enough I bet we have storage
devices which will do this for real (birth to death of the human).
--
Jay R. Ashworth
On Tue, 28 Oct 1997 19:11:09 GMT,
Tony Duell <a...@siva.bris.ac.uk> wrote:
> I also have a rack of cards to link it to a PDP11 so that graphics data
> can be recorded on it. This rack links to a DR11-B DMA interface, takes
> in data, converts it to analogue (there's a hybrid DAC module on one of the
> cards) and records it on the disk.
>
> TV action replays at one time.
You are told correctly; this is how the first Grass Valley Group slo-mo
boxed worked. TTBOMK, the heads recorded analog video data on the disk.
Cheers,
-- jra
--
Jay R. Ashworth j...@baylink.com
Member of the Technical Staff Unsolicited Commercial Emailers Sued
The Suncoast Freenet "Pedantry. It's not just a job, it's an
Tampa Bay, Florida adventure." -- someone on AFU +1 813 790 7592
Jordin Kare
> In article <kare-29109...@ppp-astk04--166.sirius.net>,
> ka...@sirius.com (Jordin Kare) wrote:
>
> > Around 1972, a friend picked up a surplus IBM "word processor"
> > (I don't think the term existed yet) based on a Selectric
> > mechanism and dating from the early Sixties...
>
> Unless I'm a generation off, it was an "MTST" -- a Magnetic Tape Selectric
> Typewriter. Very cool, for its day. I never actually saw one, but I heard
> a lot about them.
>
> The MTST... was supplanted by the "MCST," or
> Magnetic Card Selectric Typewriter,...
Yes, you are correct. Now that you mention it, I remember that
we ran across (but did not acquire) some of the MCST units
around the same time.
>
> Your mention of the tape being "dumped into a large bin one tape width
> wide, where it would pile up in 'lazy 8' loops until time to rewind it"
> reminds me of a really weird store-and-forward storage device I saw. ...
>
> The tape
> was not on a reel, as we'd presume today, but was loosely and randomly
> arrayed, one edge down and one edge up, between the glass top and the
> internal base of the unit. The write head would pull tape in and pass it
> back into the snake's nest of loose tape, and when the trigger event
> occurred the read head would then "catch up" with the write head. It was
> easily the neatest-looking device in the whole show, or maybe the whole
> world, at that time.
Actually, this kind of arrangement was common in analog tape duplication
facilities. High speed cassette duplication is done by recording
all 4 tracks (stereo in each direction) simultaneously on raw 1/8" tape,
stored on large (12" dia.) open reels, and running at anything up to
60 ips (i.e. 32X normal cassette speed). After a reel is recorded,
it is fed into empty cassette shells, with an automatic device to cut
it, attach leaders, and start a new shell at the appropriate point.
Prior to CD's, the master for the duplication process had to be
a 4-track tape, which was "played" many, many times. To avoid
rewind time (which would also mean stopping the high speed recorders,
with associated risk of stretching/breaking tapes) and probably also
to avoid the wear associated with winding on reels, the master
was in the form of a "bin loop" -- a length of tape with the ends
spliced together, dumped serpentine-fashion into a large clear-sided
bin like your coffee table top. Watching the tape cycle thru the bin
was one of those hypnotic processes, much like watching a waterfall
or (these days) a moire screen saver.
So bin loop systems were not uncommon -- but I've never seen another
one used for (quasi) random access storage...
Jordin (randomly accessed) Kare
Don Maslin
Jordin Kare (ka...@sirius.com) wrote:
And the same scheme - absent the clear-sided bin - has been used with
dot matrix printer ribbons also.
- don
: So bin loop systems were not uncommon -- but I've never seen another
: one used for (quasi) random access storage...
: Jordin (randomly accessed) Kare
do...@cts.com
*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
Don Maslin - Keeper of the Dina-SIG CP/M System Disk Archives
Chairman, Dina-SIG of the San Diego Computer Society
Clinging tenaciously to the trailing edge of technology.
Sysop - Elephant's Graveyard (CP/M) - 619-454-8412
*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*--*
see old system support at http://www.psyber.com/~tcj
Dr Pepper
On Sun, 02 Nov 1997 13:29:24 -0500, ehr...@his.com (Edward Rice)
wrote:
>In article <kare-29109...@ppp-astk04--166.sirius.net>,
>ka...@sirius.com (Jordin Kare) wrote:
>
> > Around 1972, a friend picked up a surplus IBM "word processor"
> > (I don't think the term existed yet) based on a Selectric
> > mechanism and dating from the early Sixties...
A friend of mine has a selectric typewriter the has a dial on the
right side of the top of the machine. You select a numbe, and it will
automatically type a form letter, stopping to allow you to enter such
things a names, etc. Does anybody remember these? Can anyone explain
them better than I??
Dr Pepper
Good ALL the time
:-}
William Hunt
hsh...@montagar.com (Howard S Shubs) writes:
>In article <631cvu$sgr$1...@usertest.teleport.com>, w...@usertest.teleport.com
>(William Hunt) wrote:
>>Only took it down because the client passed away.
>Like that's a reason. <grin>
no one left to sign the checks - reason enough for me :*)
>A disk drive that outlasts a human? Soon enough I bet we have storage
>devices which will do this for real (birth to death of the human).
another poster pointed out that storages devices like clay
tablets and cave walls have been shown to outlast entire
civilizations, though difficult to mount or backup.
--
William Hunt, Portland Oregon USA w...@teleport.com
Alexandre Pechtchanski
On 4 Nov 1997 05:31:49 GMT, do...@cts.com (Don Maslin) wrote:
[ Follow-ups redirected to a.f.c. only ]
>Jordin Kare (ka...@sirius.com) wrote:
>: In article <B08230B49...@0.0.0.0>, ehr...@his.com (Edward Rice) wrote:
>
>: > In article <kare-29109...@ppp-astk04--166.sirius.net>,
>: > ka...@sirius.com (Jordin Kare) wrote:
>: >
>: > > Around 1972, a friend picked up a surplus IBM "word processor"
>: > > (I don't think the term existed yet) based on a Selectric
>: > > mechanism and dating from the early Sixties...
I saw this method used in two different tape drives, both of which
were definitely (quasi) random access. One was tape drive for Soviet
Minsk-22 computers; AFAIK a clone of IBM-709. (I'm a little vague on
the details of that - after all, it was ~20 years ago, but if someone
is interested, I'll rack my brain for details of architecture). It
looked almost like more conventional reel-to-reel mainframe tape
drive, only instead of reels tape was freely dropped into thin (~ tape
width) ~10" bins on both sides of the heads, which looked almost like
vacuum columns on these more conventional drives. The other was a
block-addressable external tape memory unit for P-602/P-652 Olivetty
programmable calculators (only Olivetty called it computers ;-) The
tape unit was a kind of cassette without reels with looped tape and
some strange geared driver inside. Looped tape was S-packed inside.
[ When replying, remove *'s from address ]
Alexandre Pechtchanski, Systems Manager, RUH, NY
Edward Rice
In article <kare-03119...@ppp-astk04--169.sirius.net>,
ka...@sirius.com (Jordin Kare) wrote:
> So bin loop systems were not uncommon -- but I've never seen another
> one used for (quasi) random access storage...
I just remembered another system comparable to the "coffee table" I
mentioned. On my Apple ImageWriter, the original one, the ribbon cassettes
for cloth ribbons looked from the outside to be a pair of spools with the
ribbon moving from one to the other. If you cracked the case, though, it
became clear that it was really a loose array of ribbon moved from one side
to the other -- without spools. I was truly amazed the first time I saw
that! (It was possible, although it had to be done carefully, to open up a
cartridge, exclaim over it, and actually get it back together in working
order.)
Don Maslin
David Director (ddir...@sungardams.com) wrote:
: Jordin Kare wrote:
: > [ snip ]
: >
: > So bin loop systems were not uncommon -- but I've never seen another
: > one used for (quasi) random access storage...
: How about the Exabyte "stringy floppy"? IIRC, it was a magnetic
: tape loop that came out sometime in the mid-to-late 1970's, as a
: kind of replacement for cassette tapes. It avoided the start/stop
: and rewind overhead of the cassette, by continually running the loop
: past the heads.
: -- David
I do not believe that it was Exabyte, although the name was quite
similar. I had been under that same misapprehension until I stumbled
across the real name - and then, unfortunately, promptly forgot it 8={
- don
Tom Watson
> David Director (ddir...@sungardams.com) wrote:
> : Jordin Kare wrote:
> : > [ snip ]
> : >
> : > So bin loop systems were not uncommon -- but I've never seen another
> : > one used for (quasi) random access storage...
> : >
>
> : How about the Exabyte "stringy floppy"? IIRC, it was a magnetic
> : tape loop that came out sometime in the mid-to-late 1970's, as a
> : kind of replacement for cassette tapes. It avoided the start/stop
> : and rewind overhead of the cassette, by continually running the loop
> : past the heads.
>
> : -- David
>
> I do not believe that it was Exabyte, although the name was quite
> similar. I had been under that same misapprehension until I stumbled
> across the real name - and then, unfortunately, promptly forgot it 8={
>
The name is "exatron". They got out of that business, and went into i.c.
device handlers (for programming chips). I don't know what they are doing
now, but they are listed in the San Jose "Yellow Pages" on Yahoo. They
probably concentrate in automatic test equipment.
Logo was a lower case "e".
Stringy floppys really didn't have a life. The "real" floppies took
over. The 3.5 inch floppies were its final demise. They were cheaper,
and just as compact, had better access, and were well received.
It was a nice thought in the era of casette tape storage.
--
t...@cagent.com (Home: t...@johana.com)
Please forward spam to: anna...@hr.house.gov (my Congressman), I do.
Don Maslin
Dr Pepper (DrPe...@iwvisp.com) wrote:
: On Sun, 02 Nov 1997 13:29:24 -0500, ehr...@his.com (Edward Rice)
: wrote:
: >In article <kare-29109...@ppp-astk04--166.sirius.net>,
: >ka...@sirius.com (Jordin Kare) wrote:
: >
: > > Around 1972, a friend picked up a surplus IBM "word processor"
: > > (I don't think the term existed yet) based on a Selectric
: > > mechanism and dating from the early Sixties...
: A friend of mine has a selectric typewriter the has a dial on the
: right side of the top of the machine. You select a numbe, and it will
: automatically type a form letter, stopping to allow you to enter such
: things a names, etc. Does anybody remember these? Can anyone explain
: them better than I??
Yes, it was called the Memory Typewriter and used a wide - about 3" I
think - magnetic belt to record the data on. Turning the dial moved
the read/write head laterally and selected the track. Not long after
they were introduced, IBM came out with a field installable upgrade
that doubled the number of tracks to 100 as I recall and, of course,
the storage commensurately.
They were quite good machines for those whose storage requirements
were finite and within the capacity of the tape belt.
- don
: Dr Pepper
: Good ALL the time
: :-}
David Director
Ian Stirling
In alt.folklore.computers David Director <ddir...@sungardams.com> wrote:
And of course the 8[2-4] or so sinclair microdrive.
For use with the Sinclair Spectrum.
Interesting fact with these is if you format them twice, the
second time, they come out a little bigger, as the tape stretches,
by a significant amount.
--
Ian Stirling. Designing a linux PDA, see http://www.mauve.demon.co.uk/
----- ******* If replying by email, check notices in header ******* -----
Lord, grant me the serenity to accept that I cannot change, the
courage to change what I can, and the wisdom to hide the bodies
of those I had to kill because they pissed me off. Random
Gene Wirchenko
do...@cts.com (Don Maslin) wrote:
>David Director (ddir...@sungardams.com) wrote:
>: Jordin Kare wrote:
>: > [ snip ]
>: >
>: > So bin loop systems were not uncommon -- but I've never seen another
>: > one used for (quasi) random access storage...
>: >
>
>: How about the Exabyte "stringy floppy"? IIRC, it was a magnetic
>: tape loop that came out sometime in the mid-to-late 1970's, as a
>: kind of replacement for cassette tapes. It avoided the start/stop
>: and rewind overhead of the cassette, by continually running the loop
>: past the heads.
>
>: -- David
>
>I do not believe that it was Exabyte, although the name was quite
>similar. I had been under that same misapprehension until I stumbled
>across the real name - and then, unfortunately, promptly forgot it 8={
I tried Alta Vista and didn't find a definite, but "Exatron"?
Sincerely,
Gene Wirchenko
C Pronunciation Guide:
y=x++; "wye equals ex plus plus semicolon"
x=x++; "ex equals ex doublecross semicolon"
Robert Billing
In article <3460E9...@sungardams.com>
ddir...@sungardams.com "David Director" writes:
> How about the Exabyte "stringy floppy"? IIRC, it was a magnetic
> tape loop that came out sometime in the mid-to-late 1970's, as a
There were several versions of this, including one that used 8-track
car stereo cartridges (remember /them/?) and was sold under the trade
name Flexifile (IIRC).
john r pierce
Robert Billing <uncl...@tnglwood.demon.co.uk> wrote:
>In article <3460E9...@sungardams.com>
> ddir...@sungardams.com "David Director" writes:
>
>> How about the Exabyte "stringy floppy"? IIRC, it was a magnetic
>> tape loop that came out sometime in the mid-to-late 1970's, as a
>
> There were several versions of this, including one that used 8-track
>car stereo cartridges (remember /them/?) and was sold under the trade
>name Flexifile (IIRC).
Intecolor aka Compucolor used a 8 track for data tapes for a while. As I recall
it was a pretty funky system. Then again, the rest of the Intecolor hardware
was on the funky side too (it had some nice features and certainly was the only
RGB color system available at the time, but they were notorious for 'blowing up'
and being impossible to fix).
David Director
Shawn Sijnstra wrote:
> [ snip]
> Wasn't that Exatron stringy floppy? They were used a bit on TRS80s.
> Faster than a tape, almost as fast as a disk drive but a lot cheaper.
>
You're right, of course. I had forgotten the exact name. Exabyte
makes *real* tape drives; Exatron is long gone.
-- David
Shawn Sijnstra
David Director wrote:
>
> Jordin Kare wrote:
> > [ snip ]
> >
> > So bin loop systems were not uncommon -- but I've never seen another
> > one used for (quasi) random access storage...
> >
>
> tape loop that came out sometime in the mid-to-late 1970's, as a
> and rewind overhead of the cassette, by continually running the loop
> past the heads.
>
> -- David
Faster than a tape, almost as fast as a disk drive but a lot cheaper.
Shawn
Adam Stouffer
David Director wrote:
>
> Jordin Kare wrote:
> > [ snip ]
> >
> > So bin loop systems were not uncommon -- but I've never seen another
> > one used for (quasi) random access storage...
> >
>
> How about the Exabyte "stringy floppy"? IIRC, it was a magnetic
> tape loop that came out sometime in the mid-to-late 1970's, as a
> kind of replacement for cassette tapes. It avoided the start/stop
> and rewind overhead of the cassette, by continually running the loop
> past the heads.
Its called an "8-track"
Jay R. Ashworth
On Thu, 06 Nov 1997 01:46:07 GMT,
Gene Wirchenko <ge...@vip.net> wrote:
> do...@cts.com (Don Maslin) wrote:
> >David Director (ddir...@sungardams.com) wrote:
> >: Jordin Kare wrote:
> >: > one used for (quasi) random access storage...
> >
> >: How about the Exabyte "stringy floppy"? IIRC, it was a magnetic
> >: tape loop that came out sometime in the mid-to-late 1970's, as a
> >: kind of replacement for cassette tapes. It avoided the start/stop
> >: and rewind overhead of the cassette, by continually running the loop
> >: past the heads.
> >
> >similar. I had been under that same misapprehension until I stumbled
> >across the real name - and then, unfortunately, promptly forgot it 8={
>
> I tried Alta Vista and didn't find a definite, but "Exatron"?
I'd vote for Exatron. A client has an old set of 80 Micro which ought
to have an ad somewhere. These may go up for sale shortly, BTW; if
anyone's onterested. They start at 1:1, but I don't recall how far
forward they go. Great shape, always boxed.
john r pierce
Adam Stouffer <te...@sgi.net> wrote:
>David Director wrote:
>>
>> Jordin Kare wrote:
>> > [ snip ]
>> >
>> > So bin loop systems were not uncommon -- but I've never seen another
>> > one used for (quasi) random access storage...
>> >
>>
>> How about the Exabyte "stringy floppy"? IIRC, it was a magnetic
>> tape loop that came out sometime in the mid-to-late 1970's, as a
>> kind of replacement for cassette tapes. It avoided the start/stop
>> and rewind overhead of the cassette, by continually running the loop
>> past the heads.
>
>Its called an "8-track"
No, the 'stringy floppy' used a rather small tape, something like 1/8" wide.
The cassette was about the size of a dictating microtape like used in answering
machines. There *were* 8-track storage systems, but they had other names...
8-tracks used 1/2" tape I believe (been a LONG time since I've seen one...).
Gene Wirchenko
anti...@here.not (john r pierce) wrote:
[snip]
>No, the 'stringy floppy' used a rather small tape, something like 1/8" wide.
>The cassette was about the size of a dictating microtape like used in answering
>machines. There *were* 8-track storage systems, but they had other names...
>8-tracks used 1/2" tape I believe (been a LONG time since I've seen one...).
I'm 90% sure it was 1/4". If not 1/4", it was close. It
definitely was NOT 1/2".
Tom Watson
> David Director wrote:
> >
> > Jordin Kare wrote:
> > > [ snip ]
> > >
> > > So bin loop systems were not uncommon -- but I've never seen another
> > > one used for (quasi) random access storage...
> > >
> >
> > How about the Exabyte "stringy floppy"? IIRC, it was a magnetic
> > tape loop that came out sometime in the mid-to-late 1970's, as a
> > kind of replacement for cassette tapes. It avoided the start/stop
> > and rewind overhead of the cassette, by continually running the loop
> > past the heads.
>
> Its called an "8-track"
No, 8 track tape is something MUCH different. * track tape used 1/4 inch
tape and the cartrige was about 3 inches by 5 inches. The "stringy
floppy" was a much smaller "wafer" type thing. About the 1.5 times the
thickness of a current 3 1/2 inch floppy, and about 1/2 the size
lengthwise. The principles of tape movement were the same, but the size
was MUCH different.
Other "brilliant" ideas of the time used endless loop phillips casette
tapes (like the one used in a car stereo now), but the drive mechanisim
was wierd due to the manner of tensioning the tape with the drive reels.
Now days, we can be thankful that floppy drives cost around $20, and a
bunch of floppys go for a similar price. When I first bought a Shugart 5
1/4 inch floppy back in 1976 the drives were around $400, and the disks
were $40 for a box of 10. Times have changed, prices have dropped
considerably (understatement!).
bill_h
Herbert R Johnson wrote:
............
> As an aside, I'll note that one of the cassette standards, "Kansas
> City" if I recall, was used on a 33-1/3 RPM RECORD for a distribution
> of BASIC and some programs. Pretty scary....
A number of issues of Interface Age had a thin plastic record bound
into them. I think they not only put out a Basic or two, but even an
accounting system over several issues...... Kansas City Standard
sounds about right......
Herbert R Johnson
I hope one of the participants in this thread will compile this discussion
of tape-based file storage into a reference for the CP/M FAQ. While
not part of CP/M, such storage is part of the prior history of CP/M and
the equipment it ran on. As "Dr. S-100", I get a few to several requests
a year for information or hardware to support cassette or mag tape.
References to sites or persons with more information would be very
useful. I can, for instance, offer documentation on a number of S-100
systems or cards that supported cassettes. These included hardware products
from Technical Design Labs (TDL), Tarbell, IMSAI, Processor Tech (Sol),
and more. A reference to MS-DOS programs that use sound cards to read
old tapes as recently discussed would also be appreciated.
As an aside, I'll note that one of the cassette standards, "Kansas
City" if I recall, was used on a 33-1/3 RPM RECORD for a distribution
of BASIC and some programs. Pretty scary....
The FAQ is a very useful resource which deserves our support.
Herb Johnson
hjoh...@pluto.njcc.com
***** I do not want bulk email. Automated bulk mailings prohibited. ****
Herbert R. Johnson voice/FAX 609-771-1503 day/nite
hjoh...@pluto.njcc.com Ewing, NJ (near Princeton) USA
occasional amateur electronic astronomer
supporter of classic computers as "Dr. S-100"
and senior engineer at Astro Imaging Systems: old photons to new bits!
Harold Bower
Herbert R Johnson <hjoh...@pluto.njcc.com> wrote in article
<1qaPquoWW$TR0...@pluto.njcc.com>...
[snip]
> As an aside, I'll note that one of the cassette standards, "Kansas
> City" if I recall, was used on a 33-1/3 RPM RECORD for a distribution
> of BASIC and some programs. Pretty scary....
>
> The FAQ is a very useful resource which deserves our support.
>
> Herb Johnson
> hjoh...@pluto.njcc.com
>
Having built a 300 bps "Kansas City" interface for my first computer (an
8008) from the first or 2nd year of Byte, I used it as my primary storage
media for about a year, replacing it with an S100 card which did "KC" as
well as other rates up to 2400 bps on cassette (still have a couple dozen
casettes with SCELBAL basic programs).
The Records to which you refer might have been the "Floppy ROMs" which were
included in a couple of issues of Interface Age magazine. They had various
programs on them in different Casette (audio) formats. I actually read one
in "KC" format by copying the track from the "record" to cassette on the
Stereo system, then loading the program into the computer via the
interface. I still have the "Floppy ROM" around somewhere, and the
archived Interface Age run.
Hal
DoN. Nichols
In article <34668B...@azstarnet.com>, bill_h <bil...@azstarnet.com> wrote:
>Herbert R Johnson wrote:
>............
>> City" if I recall, was used on a 33-1/3 RPM RECORD for a distribution
>> of BASIC and some programs. Pretty scary....
>
>into them. I think they not only put out a Basic or two, but even an
>accounting system over several issues...... Kansas City Standard
>sounds about right......
There was a basic for the SWTP 6800 in KC standard, but the
accounting system was in something like Tarbell's interface standard, which
was (of course) not compatable with the KC standard.
--
NOTE: spamblocking on against servers which harbor spammers.
Email: <dnic...@d-and-d.com> | Donald Nichols (DoN.)|Voice (703) 938-4564
My Concertina web page: | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---
A. R. Ogden
Lord Almighty, that makes me feel _Very_Old_!
I remember when Priority-1 'blew-out' a bunch of
ST-506 5 meg drives at $99/ea. Heck, I even got a
couple of them to run and the last time that I looked,
one of them was in one of my Pro-350 boxes and the other
in a Rainbow.
Alan Ogden
arog @ bix dot com
Matthew Sayler
I distinctly remember Quixote Digital Typography wrote in
alt.folklore.computers:
> In article <slrn66mkne....@beret.cs.utexas.edu>,
> Matthew Sayler <mpsa...@cs.utexas.edu> wrote:
> >I distinctly remember Peter da Silva wrote in alt.folklore.computers:
> >> The Compucolor II I was exposed to had a 64x32 display with "sixel" style
> >> graphics, like the DEC ReGIS, but 8 pixels per character cell.
>
> >I'm not familiar with sixels, anyone care to elaborate?
>
> In a terminal character cell, you replace the ordinary characters with
> a 2x3 pixel matrix. 32 character slots can encompass the whole set of
> possible characters and you just output as if you're printing
> characters after shifting into "sixel mode". It's rather low
> resolution (160x72) but adequate for some applications.
>
> IIRC correctly the old TRS-80s used a similar scheme for graphics.
Is this the way the CGA 160x100x16 color mode worked, or am I
smoking crack?
m@
--
/* Matt Sayler -- mpsa...@cs.utexas.edu -- Austin, Texas
(512)457-0086 -- http://www.cs.utexas.edu/users/mpsayler
Have you ever imagined a world with no hypothetical situations? */
Peter da Silva
In article <3462ecd8...@news.scruz.net>,
john r pierce <anti...@here.not> wrote:
> Intecolor aka Compucolor used a 8 track for data tapes for a while. As I recall
> it was a pretty funky system. Then again, the rest of the Intecolor hardware
> was on the funky side too (it had some nice features and certainly was the only
> RGB color system available at the time, but they were notorious for 'blowing up'
> and being impossible to fix).
The Compucolor II I was exposed to had a 64x32 display with "sixel" style
graphics, like the DEC ReGIS, but 8 pixels per character cell. The media was
hard-sectored floppies, and the "file system" stored all files contiguously:
to delete a file meant copying the whole diskette down over the spot the
file had been, using the video memory (like the P-system did) for temp storage.
Totally funky, like they were using the floppy as a tape.
The one I played with had a bad bit in video memory (one character position
had the 'red' bit in the color stuck 'on'), so you couldn't delete any but
the last file on a floppy without corruption. Joy.
--
Insert cool quote here.
Matthew Sayler
I distinctly remember Peter da Silva wrote in alt.folklore.computers:
> graphics, like the DEC ReGIS, but 8 pixels per character cell.
I'm not familiar with sixels, anyone care to elaborate?
m@
Quixote Digital Typography
>> The Compucolor II I was exposed to had a 64x32 display with "sixel" style
>> graphics, like the DEC ReGIS, but 8 pixels per character cell.
>I'm not familiar with sixels, anyone care to elaborate?
In a terminal character cell, you replace the ordinary characters with
a 2x3 pixel matrix. 32 character slots can encompass the whole set of
possible characters and you just output as if you're printing
characters after shifting into "sixel mode". It's rather low
resolution (160x72) but adequate for some applications.
IIRC correctly the old TRS-80s used a similar scheme for graphics.
-dh
--
Don Hosek dho...@quixote.com Quixote Digital Typography
708-788-1501 fax: 708-788-1530 orders: 800-810-3311
For information about SERIF: THE MAGAZINE OF TYPE & TYPOGRAPHY,
http://www.quixote.com/serif/ or mail serif...@quixote.com
Gene Wirchenko
qui...@shell2.bayarea.net (Quixote Digital Typography) wrote:
>In article <slrn66mkne....@beret.cs.utexas.edu>,
>Matthew Sayler <mpsa...@cs.utexas.edu> wrote:
>>I distinctly remember Peter da Silva wrote in alt.folklore.computers:
>>> The Compucolor II I was exposed to had a 64x32 display with "sixel" style
>>> graphics, like the DEC ReGIS, but 8 pixels per character cell.
>
>>I'm not familiar with sixels, anyone care to elaborate?
>
>In a terminal character cell, you replace the ordinary characters with
>a 2x3 pixel matrix. 32 character slots can encompass the whole set of
^^
That should be 64. 2 to the 6th, you know.
Where did the term "sixel" come from? I never heard it in my
TRS-80 days.
>possible characters and you just output as if you're printing
>characters after shifting into "sixel mode". It's rather low
>resolution (160x72) but adequate for some applications.
>
>IIRC correctly the old TRS-80s used a similar scheme for graphics.
The Model I and Model III, yes. They used character codes 128 to
191 for this.
>-dh
>
>
>--
>Don Hosek dho...@quixote.com Quixote Digital Typography
>708-788-1501 fax: 708-788-1530 orders: 800-810-3311
>For information about SERIF: THE MAGAZINE OF TYPE & TYPOGRAPHY,
>http://www.quixote.com/serif/ or mail serif...@quixote.com
Sincerely,
Gene Wirchenko
mpsa...@cs.utexas.edu (Matthew Sayler) wrote:
>I distinctly remember Quixote Digital Typography wrote in
>alt.folklore.computers:
>> In article <slrn66mkne....@beret.cs.utexas.edu>,
>> Matthew Sayler <mpsa...@cs.utexas.edu> wrote:
>> >I distinctly remember Peter da Silva wrote in alt.folklore.computers:
>> >> The Compucolor II I was exposed to had a 64x32 display with "sixel" style
>> >> graphics, like the DEC ReGIS, but 8 pixels per character cell.
>>
>> >I'm not familiar with sixels, anyone care to elaborate?
>>
>> In a terminal character cell, you replace the ordinary characters with
>> a 2x3 pixel matrix. 32 character slots can encompass the whole set of
>> possible characters and you just output as if you're printing
>> characters after shifting into "sixel mode". It's rather low
>> resolution (160x72) but adequate for some applications.
>>
>> IIRC correctly the old TRS-80s used a similar scheme for graphics.
>
>Is this the way the CGA 160x100x16 color mode worked, or am I
>smoking crack?
Too many bits, but something similar perhaps. Given the above on
80x25, each character space had 2x4 CGA pixels. That would take up a
byte. I assume the colour would be represented elsewhere.
> m@
>
>--
>/* Matt Sayler -- mpsa...@cs.utexas.edu -- Austin, Texas
> (512)457-0086 -- http://www.cs.utexas.edu/users/mpsayler
> Have you ever imagined a world with no hypothetical situations? */
Sincerely,
Alan Cox
In article <879498...@tnglwood.demon.co.uk>,
Robert Billing <uncl...@tnglwood.demon.co.uk> wrote:
> One of the major advantages of sixel graphics was that, because only
>printable characters produce output, a page of graphics can survive a
>trip through most print spoolers. Drivers which wrap line ends also
>cause no problems. The penalty is that only 6 bits per character are
>"useful", but this is more then offset by the run length compression.
Does anyone know if the vt420 supported sixel stuff and where I might find
some useful documentation on sixels. Im developing this terrible urge to
write a getty-fishtank for the terminal downstairs
Alan
--
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Matthew Sayler
I distinctly remember Alan Cox wrote in alt.folklore.computers:
> In article <879498...@tnglwood.demon.co.uk>,
> Robert Billing <uncl...@tnglwood.demon.co.uk> wrote:
> > One of the major advantages of sixel graphics was that, because only
> >printable characters produce output, a page of graphics can survive a
> >trip through most print spoolers. Drivers which wrap line ends also
> >cause no problems. The penalty is that only 6 bits per character are
> >"useful", but this is more then offset by the run length compression.
>
> Does anyone know if the vt420 supported sixel stuff and where I might find
> some useful documentation on sixels. Im developing this terrible urge to
> write a getty-fishtank for the terminal downstairs
So does anyone have anything cute like this I could leave on the little
vt330 on my desk? (I dunno, looks like it handles vt100 to me)
john r pierce
pe...@nmti.com (Peter da Silva) wrote:
>The Compucolor II I was exposed to had a 64x32 display with "sixel" style
>graphics, like the DEC ReGIS, but 8 pixels per character cell. The media was
>hard-sectored floppies, and the "file system" stored all files contiguously:
>to delete a file meant copying the whole diskette down over the spot the
>file had been, using the video memory (like the P-system did) for temp storage.
>Totally funky, like they were using the floppy as a tape.
The Intecolor I messed with back around 76 or so(?) had a 80x24 or x25
text/'sixel' screen, same thing. soft font, 4x2 graphics possible per cell as
long as only two colors were used in each 4x2 character cell.
That file system was MS Disk Basic. In fact, the whole OPERATING system was MS
Disk Basic (or Tape Basic if you had the 8 track).
-jrp
john r pierce
ge...@vip.net (Gene Wirchenko) wrote:
>>Is this the way the CGA 160x100x16 color mode worked, or am I
>>smoking crack?
>
> Too many bits, but something similar perhaps. Given the above on
>80x25, each character space had 2x4 CGA pixels. That would take up a
>byte. I assume the colour would be represented elsewhere.
The CGA used 16 bits per character, one byte was FG/BG color, the other the
character code. I believe the Intecolor was virtually the same thing, only 5
years earlier.
Quixote Digital Typography
In article <346b7d80...@news.vip.net>,
>>In article <slrn66mkne....@beret.cs.utexas.edu>,
>>Matthew Sayler <mpsa...@cs.utexas.edu> wrote:
>>>I distinctly remember Peter da Silva wrote in alt.folklore.computers:
>>>> The Compucolor II I was exposed to had a 64x32 display with "sixel" style
>>>> graphics, like the DEC ReGIS, but 8 pixels per character cell.
>>>I'm not familiar with sixels, anyone care to elaborate?
>>In a terminal character cell, you replace the ordinary characters with
>>a 2x3 pixel matrix. 32 character slots can encompass the whole set of
> ^^
> That should be 64. 2 to the 6th, you know.
Which could be why my degree is in English Lit...
> Where did the term "sixel" come from? I never heard it in my
>TRS-80 days.
It's a DEC term from their ReGiS (or some similar randomly
capitalized) graphics terminals. When I finally got a hold of one, I
was immediately underwhelmed since I'd grown accustomed to 1024x768
Tektronix-code based terminals (I wish I could remember the
manufacturer). This was all back when I had learned enough Modula-2 to
add new terminal types into Andrew Trevorrow's DVItoVDU (was that the
right name... it's all so long ago now). At the same time I wrote my
own DVI previewer for IBM mainframes and got to deal with the joys of
IBM's graphics system whose name escapes me. It was actually not too
bad but one serious CPU hog.
Kids today with their Direct3D and memory cards with more memory than
the mainframes we used to have. The whole lot of 'em, spoiled rotten.
Peter da Silva
In article <346e1996....@news.scruz.net>,
john r pierce <anti...@here.not> wrote:
> character code. I believe the Intecolor was virtually the same thing, only 5
> years earlier.
I don't believe that is true. The CGA was, so far as I could tell, a bitmapped
display. It didn't have the color shifting problems of the Intecolor or the
Apple-II. It *was* rather low resolution, though.
Peter da Silva
In article <346b7d80...@news.vip.net>,
Gene Wirchenko <ge...@vip.net> wrote:
> Where did the term "sixel" come from? I never heard it in my
> TRS-80 days.
DIGITAL had some graphic terminals in the '70s and early '80s that used
this technique. That's the term they used.
Peter da Silva
In article <346d191d....@news.scruz.net>,
john r pierce <anti...@here.not> wrote:
> >hard-sectored floppies, and the "file system" stored all files contiguously:
> >to delete a file meant copying the whole diskette down over the spot the
> >file had been, using the video memory (like the P-system did) for temp storage.
>
> >Totally funky, like they were using the floppy as a tape.
> The Intecolor I messed with back around 76 or so(?) had a 80x24 or x25
> text/'sixel' screen, same thing.
The Intecolor line were the "professional" version. The Compucolor line
were crippled, quite severely, in an apparent attempt to avoid competing
with their own high end boxes. The wisdom of this course of action is, of
course, evident in the bankrupt corpses of many fine companies that were
clever enough to try it without establishing an unassailable monopoly
position in their chosen market first.
D. Peschel
>DIGITAL had some graphic terminals in the '70s and early '80s that used
>this technique. That's the term they used.
I don't have _The Digital Dictionary_ in front of me (it's a guide to the
terms used at Digital, Inc.) but I think it points out that "sixel" is short
for "six-pixel." Or if it isn't, it _should_ be. :)
BTW, there were two different definitions in this thread: 1) a 2x3 block of
pixels, 2) a vertical line of six pixels. I believe only number 2 is correct.
Anyway, that's the sense that the VT200 uses for defining character sets,
and I don't see why DEC's other terminals would use any other sense.
-- Derek
Ben Hutchings
In article <64t64b$5...@web.nmti.com>, Peter da Silva <pe...@nmti.com> wrote:
>In article <346e1996....@news.scruz.net>,
>john r pierce <anti...@here.not> wrote:
>> character code. I believe the Intecolor was virtually the same thing, only 5
>> years earlier.
>
>I don't believe that is true. The CGA was, so far as I could tell, a bitmapped
>display. It didn't have the color shifting problems of the Intecolor or the
>Apple-II. It *was* rather low resolution, though.
Yes, but the bitmap modes were 320*200*2 (2 bitplanes -> 4 colours) with
1 of 2 fixed palettes and 640*200*1 (1 bitplane -> 2 colours) in black
and white. (I could be wrong about the palettes.) Getting higher
numbers of colours by using one of the colour text modes is the hack.
--
Ben Hutchings, M&CS student | Jay Miner Society website: http://www.jms.org/
email/finger m95...@ecs.ox.ac.uk | homepage http://users.ox.ac.uk/~worc0223/
Experience is what causes a person to make new mistakes instead of old ones.
Josh Hesse
Ben Hutchings (worc...@sable.ox.ac.uk) wrote:
:
: Yes, but the bitmap modes were 320*200*2 (2 bitplanes -> 4 colours) with
: 1 of 2 fixed palettes and 640*200*1 (1 bitplane -> 2 colours) in black
: and white. (I could be wrong about the palettes.) Getting higher
: numbers of colours by using one of the colour text modes is the hack.
Really? My understanding of CGA(based on the EGA emulation mode) was that it
used one bitplane for both the 320*200*4color and the 640*200*2color modes.
With the bsave and bload commands of GW-BASIC, it was relativly easy to save
a picture in one mode, and then display it in the other (relative to the EGA
modes, which was a bitch, and also totally confusing untill I understood about
twiddling registers to switch between planes(the default for read was the first
(lowest)plane, and the default for write was all four planes)).
Anyways,
011010000111001110000110 on the bit-plane would be displayed as:
2 1 1 0 2 3 0 3 1 0 2 1 in four color mode(or something like that, I was more
intersested in EGA modes), and
011010000111001110000110 in two color mode.
-Josh
--
Do not send mail to this account. Really.
"Talk about silly conspiracy theories..." -Wayne Schlitt in unl.general
This post (C)1997, Josh Hesse. Quoted material is (C) of the person quoted.
|ess|erb|unl|u|
email: jh|e@h|ie.|.ed|
Vote for "citizan" Bob! <http://www.wtv.net/trustee/>
john r pierce
pe...@nmti.com (Peter da Silva) wrote:
>In article <346e1996....@news.scruz.net>,
>john r pierce <anti...@here.not> wrote:
>> The CGA used 16 bits per character, one byte was FG/BG color, the other the
>> character code. I believe the Intecolor was virtually the same thing, only 5
>> years earlier.
>
>I don't believe that is true. The CGA was, so far as I could tell, a bitmapped
>display. It didn't have the color shifting problems of the Intecolor or the
>Apple-II. It *was* rather low resolution, though.
Ah, um. The CGA had several 'modes'. I was describing the 80x25 16 color TEXT
mode, which could be perverted into a non standard 160x200 16 color graphics
mode.
You are describing the 640x200 monochrome graphics mode (1 bit per pixel). It
also had a 320x200 2bit per pixel graphics mode (4 colors, with a very limited
palette; color '0' could be any of the 16, but colors 1,2,3 were restricted to
either red/green/yellow or magenta/cyan/white). In fact, in the 640x200 mode,
you could enable comp video colors and output to a TV set, getting the same
color fringing the apple-II had. Virtually noone did this however, the standard
CGA monitor was a ttl level RGB+I (intensity) monitor that could display 16
colors.
The Intecolor's I remember were RGB and had no color shifting problems.
Mike Morris
In article <3477A37A...@stoneweb.com> "Carl R. Friend" <carl....@stoneweb.com> writes:
>From: "Carl R. Friend" <carl....@stoneweb.com>
>Subject: Re: Q: Interest in ST-506 drives
>Date: Sat, 22 Nov 1997 22:31:06 -0500
>Mike Morris, in article
>nr. <morris.162...@SPAMBLOCKcogent.net> wrote:
>>
>> Someday I'll
>> find a museum that appreciates a 5 meg drive, my 4004, 4040, 8008,
>> AMD Hex-29, AMD Super16, PDP-1, Lockheed SUE and V-620i books.
>> Maybe even my DG Nova (my second home computer - you had to unplug
>> the stove to plug it in...)
> What sort of Nova is it that it requires 220? They all came
>standard from the factory strapped for 115 VAC. 220 was an option.
The wiring was set for 220 when I got it, and it happened to have
the same plug as the stove. The wiring was different and unusual
enough that I wanted to see the proper drawings rather than try the
115v conversion without them. Since I could use it as it was, I
left it that way. Later on I got the right drawings, and converted
it. I later got rid of the Nova when I got a Nova 4.
--
Mike Morris ham radio: WA6ILQ ICBM: 34:07:54.9 by 118:03:46.2
The above is my own opinion and should not be construed to be that of any of
my former or my current employers. The reply address is spoofed to discourage
junk email, please remove all the capital letters from the address.
Mike Morris
In article <34767782...@192.189.54.145> r...@redplanet.mars.org.cy (Rotes Sapiens) writes:
>From: r...@redplanet.mars.org.cy (Rotes Sapiens)
>Subject: Re: Q: Interest in ST-506 drives
>I've got a ST-50x 10Mb drive, it's 15 years old and it still works!
>They seem to last forever, not like today's high performance drives.
The quality control wasn't as good, so they were overbuilt, hence they
last. Kinda like the old IBM AT keyboards, Dodge Power Wagons, and mid-
1960s Volvo 122S station wagons (over 768,000 miles, never had the
cylinder head off, can anyone beat that?).
I have two of those Priority-one ST506s. Both are still in the sealed bag,
one is in the styrofoam blocks, the other is missing the blocks. Someday I'll
find a museum that appreciates a 5 meg drive, my 4004, 4040, 8008, AMD Hex-29,
AMD Super16, PDP-1, Lockheed SUE and V-620i books. Maybe even my DG Nova
(my second home computer - you had to unplug the stove to plug it in...)
Note: empty 2315 pack cases make good thin planter stands - and excellent
conversation starters - you always hear "Is that what I think it is?"...
---------------------------------------------------------------------------
Mike Morris ham radio: WA6ILQ ICBM: 34:07:54.9 by 118:03:46.2
The above is my own opinion and should not be construed to be that of any of
my former or my current employers. The reply address is spoofed to discourage
junk email, please remove the capital letters from the address.
Carl R. Friend
Mike Morris, in article
nr. <morris.162...@SPAMBLOCKcogent.net> wrote:
>
> find a museum that appreciates a 5 meg drive, my 4004, 4040, 8008,
> AMD Hex-29, AMD Super16, PDP-1, Lockheed SUE and V-620i books.
> Maybe even my DG Nova (my second home computer - you had to unplug
> the stove to plug it in...)
What sort of Nova is it that it requires 220? They all came
standard from the factory strapped for 115 VAC. 220 was an option.
--
______________________________________________________________________
| | |
| Carl Richard Friend (UNIX Sysadmin) | West Boylston |
| Minicomputer Collector / Enthusiast | Massachusetts, USA |
| mailto:carl....@stoneweb.com | |
| http://www.ultranet.com/~engelbrt/carl/museum | ICBM: N42:22 W71:47 |
|________________________________________________|_____________________|
Callum Lerwick
On 24 Nov 1997 01:36:30 GMT, ave...@macabre.kaelos.apana.org.au
(Andre van Eyssen) wrote:
>In article <3474a993...@news.scruz.net>, john r pierce wrote:
>>
>>Ah, um. The CGA had several 'modes'. I was describing the 80x25 16 color TEXT
>>mode, which could be perverted into a non standard 160x200 16 color graphics
>>mode.
>
>Which was quite cool, and a number of s/w game authors exploited this little
>trick to the full. Pity of the matter was ... that anything greater than a
>CGA display broke the games :-(
Check out http://boxotrix.it-ias.depaul.edu/lbd/ you'll find an
explination of how the 160x100 mode works...
Actually, you're getting the 160x100 mode and 160x200 mode confused.
160x100 was the text mode from hell, 160x200 was just the 640x200
monochrome mode with the pixels placed just right to create color
smear on composite monitors, Apple II style. This doesn't work on a
RGB display. And doesn't seem to work on my particular CGA card, it
seems you can't disable the "color killer" circuit... :P
Rotes Sapiens
On 11 Nov 1997 12:25:47 GMT, "A. R. Ogden" <ar...@delphi.com> wrote:
>Lord Almighty, that makes me feel _Very_Old_!
>I remember when Priority-1 'blew-out' a bunch of
>ST-506 5 meg drives at $99/ea. Heck, I even got a
>couple of them to run and the last time that I looked,
>one of them was in one of my Pro-350 boxes and the other
>in a Rainbow.
I've got a ST-50x 10Mb drive, it's 15 years old and it still works!
They seem to last forever, not like today's high performance drives.
The five food groups are not beer, pizza, burgers, chips and
chocolate.
Ian Stirling
In alt.folklore.computers Rotes Sapiens <r...@redplanet.mars.org.cy> wrote:
: On 11 Nov 1997 12:25:47 GMT, "A. R. Ogden" <ar...@delphi.com> wrote:
: >Lord Almighty, that makes me feel _Very_Old_!
: >I remember when Priority-1 'blew-out' a bunch of
: >ST-506 5 meg drives at $99/ea. Heck, I even got a
: >couple of them to run and the last time that I looked,
: >one of them was in one of my Pro-350 boxes and the other
: >in a Rainbow.
: I've got a ST-50x 10Mb drive, it's 15 years old and it still works!
: They seem to last forever, not like today's high performance drives.
The ones that last "forever" did not fail 15, 14.75, 14.5 ... years ago.
You have therefore selected the ones that had no faults/unreliabilities.
: The five food groups are not beer, pizza, burgers, chips and
: chocolate.
--
Ian Stirling. Designing a linux PDA, see http://www.mauve.demon.co.uk/
----- ******* If replying by email, check notices in header ******* -----
"Looks like his brainwaves crash a little short of the beach..." Duckman.
Clarence Wilkerson
I got one of these to fail by trying to eke a few extra
cylinders out. No fancy micorprocessor control unit to
lock out illegal ranges.
Clarence
Andre van Eyssen
In article <3474a993...@news.scruz.net>, john r pierce wrote:
>
>Ah, um. The CGA had several 'modes'. I was describing the 80x25 16 color TEXT
>mode, which could be perverted into a non standard 160x200 16 color graphics
>mode.
Which was quite cool, and a number of s/w game authors exploited this little
trick to the full. Pity of the matter was ... that anything greater than a
CGA display broke the games :-(
--
(new-style low-fat sigfile)
_____________________________________________________________________________
Andre van Eyssen, | "It was a piece of subtle refinement that God
Kaelos Computing (T4216908), | learnt Greek when he wanted to be a writer -
Deputy Coordinator, | and that he did not learn it better"
Hunter Region APANA. | Nietzsche, Beyond Good and Evil (Maxims 121)
-----------------------------------------------------------------------------
"The Americans spent $500,000 developing a pen that would work
in a weightless environment. The Russians used a pencil."
-----------------------------------------------------------------------------
john r pierce
wil...@hopf.math.purdue.edu (Clarence Wilkerson) wrote:
hah! step and direction went DIRECTLY to the stepper motor drivers... But they
shouldn't have permanently failed, rather, just made nasty noises letting you
know that you'd hit the hard stop. If you drove them repeatedly into said hard
stop, I suppose that could overheat the stepper motor or something?
Clark Geisler
In article <3477A37A...@stoneweb.com>, "Carl R. Friend" <carl....@stoneweb.com> wrote:
>Mike Morris, in article
>nr. <morris.162...@SPAMBLOCKcogent.net> wrote:
>>
>> Someday I'll
>> find a museum that appreciates a 5 meg drive, my 4004, 4040, 8008,
>> AMD Hex-29, AMD Super16, PDP-1, Lockheed SUE and V-620i books.
>> Maybe even my DG Nova (my second home computer - you had to unplug
>> the stove to plug it in...)
>
> What sort of Nova is it that it requires 220? They all came
>standard from the factory strapped for 115 VAC. 220 was an option.
The 220V on a stove plug is really 2 110V circuits, 180 degrees out of
phase with each other. He might be just using one of the 110 legs on a
stove outlet just so he can get enough current (stove wiring is good for, say
30 or 40 amps?). I'm planning to power up my VAX 11/730 some day that way...
--
Clark Geisler
Test Engineer, Nortel, Lentronics division, Burnaby, BC, Canada
* fix my e-mail address as required.
Adam Stouffer
Andre van Eyssen wrote:
>
> In article <3474a993...@news.scruz.net>, john r pierce wrote:
> >
> >Ah, um. The CGA had several 'modes'. I was describing the 80x25 16 color TEXT
> >mode, which could be perverted into a non standard 160x200 16 color graphics
> >mode.
>
> Which was quite cool, and a number of s/w game authors exploited this little
> trick to the full. Pity of the matter was ... that anything greater than a
> CGA display broke the games :-(
>
I think Space Quest III from sierra had great graphics for CGA. It ran
on my 4.77mhz Tandy 1000 HX.
--
-----------------------------------------------------
| |
| Remove the NO-SPAM from my address to mail me. |
| |
-----------------------------------------------------
Clarence Wilkerson
The $99 ST-506 drives I got in mid 80's were subject to
"stiction". My friends and I used to joke about having to
"rope " start them, like a lawnmower.
Clarence
James W. Birdsall
Andre van Eyssen wrote:
> Which was quite cool, and a number of s/w game authors exploited this little
> trick to the full. Pity of the matter was ... that anything greater than a
> CGA display broke the games :-(
My ATI VGA Wonder (512K) came with a batch file that used undocumented
(or at least obscure) arguments to the card's configuration programs to put
it into a mode where those games would work. The batch file was documented,
and the documentation specificially mentioned ROUND42, an odd little
shareware shoot-em-up that I was fond of at the time.
--
James W. Birdsall http://www.picarefy.com/~jwbirdsa/ jwbi...@picarefy.com
"For it is the doom of men that they forget." -- Merlin
Get the Sun Hardware Reference from ftp.picarefy.com:/pub/Sun-Hardware-Ref
Sun Hardware Reference Web Page: http://www.picarefy.com/~jwbirdsa/sun-temp/
Rotes Sapiens
>In alt.folklore.computers Rotes Sapiens <r...@redplanet.mars.org.cy> wrote:
>: On 11 Nov 1997 12:25:47 GMT, "A. R. Ogden" <ar...@delphi.com> wrote:
>: I've got a ST-50x 10Mb drive, it's 15 years old and it still works!
>: They seem to last forever, not like today's high performance drives.
>The ones that last "forever" did not fail 15, 14.75, 14.5 ... years ago.
>You have therefore selected the ones that had no faults/unreliabilities.
I appreciate the selective, sample 1 out of 1 nature of my comment. I
was just making conversation. After all, this is comp.os.misc, not
alt.tech.100%.correct.or.else.
Ian Stirling
: <00003477A...@mauve.demon.co.uk> wrote:
It wasn't really based on stats, more on my experience of hard drives
of that era.
My personal experience has been that properly cooled, modern drives,
as long as they arn't from a bad batch are much more reliable.
--
Ian Stirling. Designing a linux PDA, see http://www.mauve.demon.co.uk/
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Two fish in a tank: one says to the other, you know how to drive this thing??
John Thompson
>The five food groups are not beer, pizza, burgers, chips and
>chocolate.
Darn right. What happened to caffeine?
-John (John.T...@ibm.net)