The Processor Technology SOL-20 with a semi-working Helios Disk System whose
listing I am start this evening (Thurs, 11/19, at about 10pm EST) on E-Bay
uses 8" 32-sector hard sector diskettes (and comes with two boxes of them).
Wang systems also used these same diskettes, but, oddly, what we call the
"back" of the diskettes was the "front" on Wang systems; they inserted them
into the drive backwards by normal standards. The drive in the Helios is a
Persci drive, just jumpered differently than for soft-sector use.
There is (or was) also a very rare and unusual 32-sector 8" hard sector
diskette where the sector holes were at the outer edge of the diskette
circumference. Not sure who used this, but I know it existed.
I believe that there was also a 16-sector 8" diskette, but I'm not sure.
The number of sectors is related to sector size (Duh !!). In fact, the
Helios, which had hardware variable sector sizes, defaults to using only
every other sector hole and double-size sectors (in other words, I believe
that it effectively has 16 sectors of 256 bytes per track, even though the
diskette has 32 sector holes). By having fewer larger sectors, you
effectively convert the otherwise lost inter-sector gaps into data space and
increase the capacity of the media (this is true for soft sector as well).
In the 5.25" size, I know that there was both 10-sector and 16-sector media.
Heathkit/Zenith and NorthStar both used the 10-sector media.
Subject: Re: Hard-sector discs -- how many sectors?
On Thu, 19 Nov 2009, Philip Pemberton wrote:
>> Specifically, how many sectors can you actually get on a
>> hard-sectored disc? I know 10- and 16-sector discs were (are?)
>> available, but were any larger sizes (e.g. 20 or 30 sectors) ever made?
> Wang sometimes used 32 SPT hard-sectored
> I would NOT dare to claim that any list is exhaustive.
------------------------------
Item # 190348608036
The seller claims this is a vintage computer from 1968.
It's all been de-racked and is shown spread out on a table,
local pickup only in Hudson, MA. There is a console that
appears to have been part of medical instrumentation of
some kind. I don't recognize the manufacturer's label
that is shown, but there is a set of drawings, and the
card cage appears to contain a core stack or two.
Someone local might want to check it out.
Item # 120492284400
These look like raw ceramic substrates similar to those used
for IBM's SLT logic, but they appear to be set up with pads
for larger die. Perhaps MST logic? Anway, the seller claims
they are IBM material from the 1970's. There's a whole tray
of them, as would be used in manufacturing. Could be interesting
for the IBM mainframe collectors.
I would like to build a RGB-VGA converter but I don't know how to design one. If you have a circuit diagram, I would like to obtain it.
I have an old RS6000 320H computer which has RGB 3 BNC with sync on green. It also says "separate". It also says that 1280 * 1048(something like that). The original monitor (IBM 6091-19)has H freq =63.35kHz (something like that), V = 60 Hz.
Could you help me with the circuit?
Thanks
Chungduck Ko
It has been over 10 years since I used VMS, but I seem to remember
that there was a feature available called Symbolic Name List which
is a superset to (and MUCH superior to) the PATH name in DOS.
I no longer have access to the Grey Wall, so I attempted to look in
bitsavers. No luck at all.
Can anyone provide a link to a PDF of the VMS manual which
contains to documentation for SNL in VMS. Also, is this feature
to same in both the VAX and Alpha at this point? If there is a
difference? Which seems to be better? Is there a separate PDF
for the documentation in each case?
Jerome Fine
I have a 3 M data cartridge drive and i can't use it so looking for someone needing one...? Probably from 1980 or so and I have some pictures I can send if interested...
I'm working on a Tomy Tutor tape decoder because, well, no one else is. To
that end, this weekend I managed to crack the encoding and now have a
primitive tape decoder that reads an AIFF audio file and spits out bits for
a higher-level decoder to process. To date I can now see the bit pattern for
the GRAPHIC paintbox, and can even do rudimentary decoding of BASIC programs.
So far so good.
However, playing back that exact uncompressed 44.1kHz 16-bit mono AIFF into
the Tutor doesn't work (before you ask, the Tutor's tape inputs are mono).
The Tutor doesn't see the sync mark, and never loads the "tape." I recorded
this a few times, making sure that all the output got on the audio file,
and no dice. I also played with line levels and varied the output volume
level through all the fine steps the Mac would let me step, and the Tutor
just sits there.
Have people discovered any gotchas in general about using PC audio files
to load and save from tape, besides the obvious ones like don't compress,
etc.? Any suggestions about how to make the Mac's output more acceptable
to the Tutor?
--
------------------------------------ personal: http://www.cameronkaiser.com/ --
Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckaiser at floodgap.com
-- Adore, v.: To venerate expectantly. -- Ambrose Bierce ----------------------
Hi! Does anyone know what hardware Motorola originally used to demonstrate
the 6809? I am referring to the hardware Motorola references in the 6809
programming manual. It is the hardware that Motorola wrote their ASSIST09
debug monitor to run on. The reason I am asking is to understand how they
are connecting the output of timer #1 of the MC6840 PTM to the CPU /NMI
line. Specifically, is it directly connected or inverted? Is other logic
involved or further qualifications? Does anyone have schematics available
of the original Motorola 6809 hardware?
The ASSIST09 source code implies a direct connection but that is counter
intuitive to me since the /NMI line is active low and the PTM timer #1 is
active high. The ASSIST09 monitor uses the PTM connected to the /NMI line
for hardware assisted tracing. According to the datasheet for the 6809 and
6840, the /NMI is activated on the negative transition which would be on the
falling edge of the pulse from the PTM timer output if directly connected.
If inverted, it would be on the leading edge of the pulse.
The reason I need this information is I am building an IO mezzanine board
(ACIA, PTM, dual VIAs) for the N8VEM 6809 host processor. The good news is
that I've seen the hardware assisted tracing work using the inverted output
of the timer. However, the IO mezzanine is connected to the 6809 host
processor by ribbon cables which are notorious for causing signal delays and
other problems. As a result, the tracing is unreliable and I would like to
fault isolate. The rest of ASSIST09 seems to be working reliably on my
prototype hardware.
Originally, I presumed Motorola designed the ASSIST09 monitor for the
EXORset system since it was their first 6809 based computer and released
about the same time as the 6809's introduction.
If anyone has familiarity with the original Motorola hardware for the
ASSIST09 debug monitor I would appreciate your help. Thanks in advance and
have a nice day!
Andrew Lynch
I refer to these two functions in the ASSIST09 source code:
**************************************************
* [SWI FUNCTION 8]
* MONITOR ENTRY
* FIREUP THE ASSIST09 MONITOR.
* THE STACK WITH ITS VALUES FOR THE DIRECT PAGE
* REGISTER AND CONDITION CODE FLAGS ARE USED AS IS.
* 1) INITIALIZE CONSOLE I/O
* 2) OPTIONALLY PRINT SIGNON
* 3) INITIALIZE PTM FOR SINGLE STEPPING
* 4) ENTER COMMAND PROCESSOR
* INPUT: A=0 INIT CONSOLE AND PRINT STARTUP MESSAGE
* A#0 OMIT CONSOLE INIT AND STARTUP MESSAGE
*************************************************
SPC 1
SIGNON FCC /ASSIST09/ SIGNON EYE-CATCHER
FCB EOT
SPC 1
ZMONTR STS <RSTACK SAVE FOR BAD STACK RECOVERY
TST 1,S ? INIT CONSOLE AND SEND MSG
BNE ZMONT2 BRANCH IF NOT
JSR [VECTAB+.CION,PCR] READY CONSOLE INPUT
JSR [VECTAB+.COON,PCR] READY CONSOLE OUTPUT
LEAX SIGNON,PCR READY SIGNON EYE-CATCHER
SWI PERFORM
FCB PDATA PRINT STRING
ZMONT2 LDX <VECTAB+.PTM LOAD PTM ADDRESS
BEQ CMD BRANCH IF NOT TO USE A PTM
CLR PTMTM1-PTM,X SET LATCH TO CLEAR RESET
CLR PTMTM1+1-PTM,X AND SET GATE HIGH
LDD #$01A6 SETUP TIMER 1 MODE
STA PTMC2-PTM,X SETUP FOR CONTROL REGISTER1
STB PTMC13-PTM,X SET OUTPUT ENABLED/
* SINGLE SHOT/ DUAL 8 BIT/INTERNAL MODE/OPERATE
CLR PTMC2-PTM,X SET CR2 BACK TO RESET FORM
* FALL INTO COMMAND PROCESSOR
SPC 3
*******************TRACE - TRACE INSTRUCTIONS
******************* . - SINGLE STEP TRACE
CTRACE BSR CDNUM OBTAIN TRACE COUNT
STD <TRACEC STORE COUNT
CDOT LEAS 2,S RID COMMAND RETURN FROM STACK
CTRCE3 LDU [10,S] LOAD OPCODE TO EXECUTE
STU <LASTOP STORE FOR TRACE INTERRUPT
LDU <VECTAB+.PTM LOAD PTM ADDRESS
LDD #$0701 7,1 CYCLES DOWN+CYCLES UP
STD PTMTM1-PTM,U START NMI TIMEOUT
RTI RETURN FOR ONE INSTRUCTION
SPC 3
Can you guys please change the subject of your posts to "Rare minerals" or something.
?
When I see a header that purports to talk about "Non-fake Apple 1 on ebay", I'm kinda hoping the message body actually contains text that the subject refers to...
?
Thanks!
Hi all!
I'm somewhat swamped in old computer gear and thought I should see if
anyone wants to take care of my Norsk Data ND-110/CX. It is a rather
large machine, as can be seen on toresbe's site:
http://folk.uio.no/toresbe/nd/history_files/nd-100.jpg
It comes with a matching terminal with keyboard, just as on the picture.
I have gotten it boot, but it probably needs a bit of love.
So, free for pickup in Uppsala Sweden. If you want it shipped I will
need some "motivation".
If nobody wants it, it will go into longtime storage, this is not a
rescue call.
Cheers,
Pontus.
