Date: Sat, 7 Apr 2007 12:29:49 -0500
From: "Ethan Dicks" <ethan.dicks at gmail.com>
Subject: Re: ST506 WTB:Micropolis 1325
<snip>
>There were probabably a few others. I doubt there were any 3.5"
>drives over 40 MB, though.
<snip>
Seagate ST151 and 157R, just to name two...
>> The largest MFM drive ever made was _probably_ the Maxtor 2190 at 190MB
>> unformatted. ISTR that there was a logical limit to the number of
>> cylinders due to the control protocol (or perhaps limitations in the PC
>> BIOSes of the time) and physical limits to the number of sectors/cylinder
>> and the number of platters (the 2190 had 15 or 17?)
>That's certainly close to the largest, if not the absolute largest.
>DEC took the XT2190 and formatted it at 154MB as the RD54. I have a
>few in MicroVAXen. Much more solid than the RD53 (Micropolis 1325),
>and no jumper moving required (there's a single solderable jumper that
>must be installed to turn a generic 1325 into an RD53 so that the
>customer-runnable formatter recognizes it).
>-ethan
XT1240R: 196MB (RLL2,7) vs XT2190: 159MB (MFM)
m
I've seen a bunch of more or less generic, 8-bit capable, allegedly bootable
ISA cards based on the 53c80 & 53c90 over the years. It's a really
widespread family, and it supported by many OSes. The various c90 variants
were quite good for the time. I didn't spend that much time with 8-bit ISA
systems, so I can't be in any way authoritative on which ones would work.
The 53c400 is also 8-bit capable, and near as I can figure you can get cards
with them for a penny a pound, but I've never seen one with a boot rom, and
while there are claims that you can put a disk on one, I've never seen one
do anything more than drive a scanner.
I'm pretty sure the AIC-6260 & AIC-6360 can do 8-bit, but it's also one I've
never seen with a boot rom (which means little). In fact, I've only seen
one example that wasn't on a sound card.
Ken
>
>Subject: Re: IBM PC printer adapter schematic
> From: "Ethan Dicks" <ethan.dicks at gmail.com>
> Date: Sat, 07 Apr 2007 18:29:29 -0500
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>On 4/7/07, Tony Duell <ard at p850ug1.demon.co.uk> wrote:
>> I wrote:
>> > That's handy to know - every once in a while, I long for a machine
>> > with 2 or 3 parallel adapters, for things like old Connectix cameras,
>> > LCD displays and the like. I've never assembled an ISA machine with
>> > more than one printer adapter....
>>
>> Well, you can have as may printer adapters as yopu like if you can set
>> them all to different addresses and if you're writing your own software
>> to talk to them...
>
>Naturally. The problem I see is that only the older cards might let
>you set the printer port to respond to arbitrary addresses - the ones
>I have are almost (entirely?) all of the style where you move a single
>jumper for LPT1 vs LPT2 (primary vs secondary address).
>
>I wasn't as worried about the OS interpretation since I don't intend
>to *print* to my printer port.
The current system has three printer ports in it! No big deal and there
are standard addesses that the OS (win or nt) recognize with no difficulty.
I use three as one is dot matrix (LQ570), one Laser (HP4l) and the third
is inkjet(color). I happen to be using the a PCI, ISA and mainboard
based ports so where's the problem?
All the ISA cards I have allow for at least two if not many more possible
printer ports. And same for serial, though after two the IRQ assignments
can be weird.
Allison
> Your assumption is correct. You'll probably want the RT PC Options
> Installation manual off my site:
Dug around and found my hardware tech ref vol 1. Should I scan it?
> I'm still concerned about what documentation and resources there are out there
> for the cat though - I mean quite a few must have been sold, and owners must
> have thrown together quite a bit of code to drive them - but every time I've
> dug around on the 'net it's been unclear as to what kind of user community
> exists to actively share code and experiences.
This list would be a good place for it. I know of code that was done to read
a couple of different hard-sectored formats (DG and Processor Tech) I was just
looking at hacking that to read some Tektronix 8002A development system discs
(hard sectored 32/trk)
Intel M2FM would be very useful to read as well.
> I'm curious if anyone knows about VG datasystem 2000 or
> System Industries.
System Industries was a fairly well known manufacturer of third
party disk subsystems
I've seen VG Datasystems before, but I don't remember the context
Maybe I'm just thinking of Vector General, though.
After finding an IBM portable PC in the trash, I did the usual restoration
and now it's time to have fun.
I grabbed a Trantor T130B scsi card and set it as follows:
IRQ---5
I/O---340H
Bios address---CA00H
I then attached a seagate ST-296N 80+ meg hard drive, set it to ID 1 and
powered the system on.
The card detects the drive and the system addresses it as C: and then
because the drive is not formatted I have to floppy boot and patition and
format it.
This is where things got strange.
As the floppy loads, the drive works a bit and the activity lamp comes on
and stays on, then the floppy drive stops loading and I need to do the three
fingered salute. (ctrl+alt+del)
The hard drive lamp stas on and the second floppy boot is successful but
fdisk errors out with no fixed disks present. I thred several different dip
switch settings on the card, all go the same way except for a few when the
system can't even see the card. The boot floppy holds DOS 3.30 and came from
an ACER system since I did not receive any origional floppies with the
system, just two games and a damaged DOS 6.2 disk
What's going on? The termination and cables are fine and should I set zero
wait state to on or off? I currently have it set to off.
EDIT:
For some strange reason, the ROM on the card takes over the boot when no
scsi devices are installed.
Usually what happens is that if the system can't find anything to boot from,
it will dump you into the onboard BASIC. When the card is installed and
there is nothing to boot from, I instead get "looking for SCSI or floppy
devices to boot from". Is there anyway for me to stop it looking for
something to boot from and go to BASIC? To me it really limits me to using
basic off disks.
_________________________________________________________________
This Easter, Get Active With Live Maps!
http://local.live.com/?mkt=en-ca/?v=2&cid=A6D6BDB4586E357F!101
It's the fan. No doubt about it, it's the fan in the back of the RX02
causing the RL02 to fault.
I disconnected the fan and the RL02 no longer faults upon spinup. The moment
I put the molex back on the fan of the RX02 - the RL02 immediately faults.
I decided to take a closer look at this fan in the back of the RX02, so I
took out the 4 screws and pulled off the plastic "wedge shaped" housing. The
fan in there is one of those older odd-looking ones. Not sure how to
describe it. Instead of your "normal" muffin fan where the windings are hard
to see and they are around the hub... this is the kind where the fan hub
sits on one side of a large rectangular hunk of iron? Steel? I dunno... big
chunk of heavy metal :)
Betcha if I replace that fan with the more normal kind I don't have such a
problem. The current fan isn't noisy, works good... but I'm betting the huge
coil on it is a problem.
Jay
Just in case someone doesn't know this, you can look up any old HP part
(and now Agilent) at:
http://www.parts.agilent.com
In some cases they will show a picture. If you lookup said part, you
will find this:
Part Number: 1858-0054
Description: Mod and Ser Nbr Reqd TRANSISTOR ARRAY 16-PIN PLSTC DIP
Price: $10.25
Quantity on Hand:
Item Status: Limited Supply - Contact Agilent
Item Type: Agilent Qualified Part
And, they list all products where they know it to be found.
