In the 'Are you as crazy as me' catagory, I just found something that looks
really, really cool. Anyone for running OS/360 on your Linux box? If so
meet Hercules!
http://www.snipix.freeserve.co.uk/hercules.htmhttp://jmaynard.home.texas.net/hercos360/
Something tells me I just found a use for that Dual 400Mhz Celeron I've got,
as this looks to require some *SERIOUS* horsepower to run!
OH, Wow!!! :^)
Zane
PS now if I wasn't *still* stuck at work with problems! :^(
From: "Stephanie Ring"
sring(a)uslink.net
I would like to know what material can
be substituted for the black slide on
3.5 floppies when these are missing,
on the right hand top corner.
We used PDP 11/04's with a cassette drive to collect microbiology data.
There is nothing more frustrating than coming in in the morning and finding
the cassette tape drive trying to write to the cassette and rocking back and
forth on the same spot until the oxide is worn off. We didn't have enough
memory to store all of the data in the PDP-11 and there were no disk drives
in the system. The entire program was loaded into a PROM and booted the
machine. It was one large program that monitored the incubator, moved the
test kit carousel, removed the cards, read the optical transmittance, and
did the data analysis. The console was a VT-52 with the hard copy option.
Even earlier incarnations had PDP 11/05's with core memory.
I seem to remember that we were excited when the RX01's came out, we
purchased DSD versions and wrote the data to 8" floppies. We wrote data to
the correct sector and when we were done the data was in a RSX usable file.
What memories.
Mike
michaelmcfadden(a)sprintmail.com
I've always used a strip of black electrical tape. It'll work with either
mechanical or optical sensors.
Steve Robertson <steverob(a)hotoffice.com>
> > From: "Stephanie Ring"
> > sring(a)uslink.net
> >
> >
> > I would like to know what material can
> > be substituted for the black slide on
> > 3.5 floppies when these are missing,
> > on the right hand top corner.
Friends,
I got an IBM disk (from a PS/2 55SX) I would like to use. It is presumable
an SCSI one with the following flood of numbers on it.
P/N 6128256 FRu P/n 6128272 MLC C13052 Model WD-387T
Is there somewhere a site with data of such a disk, with the pinnout or can
anyone send me the data?
Thanks in advance
Wim Hofman
saw one when doing my thrift store runs. opened but still in box. looks like
it might be a refurb unit. looks like just a bigger 64.
DB Young ICQ: 29427634
view the computers of yesteryear at
http://members.aol.com/suprdave/classiccmp/museum.htm
--You can lead a whore to Vassar, but you can't make her think--
> Did you do "@ SYS$MANAGER:TCPIP$CONFIG.COM"? What are everyone's IP
> addresses? What failed? How?
Yes, ofcourse and IPs are OK also. Bou I've double-checked my PC
networking and I've fount that it works fine on twisted pair, howewer
there are problems wiht thin wire. I,ve to try another network card.
Maciek
The C64 Serial _PORT_
The C64 Kernal does have routines that implement a serial port
using certain pins on the C64 User Port. But if you don't mind
writing your own driver then theoretically speaking all you
need to implement a bidirectional serial port is two bits on a
port with the capability of defining one as input and the other
as output (the input bit should be capable of generating an
interrupt), and a ground reference. And if you want RS-232C
signal levels (many computers and other serial devices are
just fine with TTL level signals) you need to add a RS-232
driver and receiver to the interface. Back then that meant
the 1488 and 1489. Today you have the ADM202,MAX202 and the
LT1181.
There is a problem with the C64 RS-232 Kernal routines. It
turns out that the time they take to process one bit plus the
timer value for one 1200 baud bit time was slightly more than
one 1200 baud bit time. By the 8th bit, the timer interrupt is
happening more than 1/2 bit time late, missing a bit. This is why
in the early days (before 1985) people had to set the serial
port speed to 1210 baud in order to receive reliably at 1200
baud. And of course you really needed two stop bit time to
to prepare for the next byte. I really believe that our group
wrote the first serial driver to allow the C64 to run full
speed at 1200 baud.
If you don't need interrupt driven serial routines, we use
to do our software development on the Stratus and then download
to the C64s in our offices using a serial cable that plugged into
one of the joystick ports. Software in the C64 would bit-bang
the joystick port at 9600 baud (with the screen blanked).
The C64 Serial _BUS_
All fast serial disk software for the C64 can actually be
traced back to those clever C64 users in Germany, they did it
first. I reverse engineered the Epyx cartridge about 1985.
Yes, bits were transfered two at a time with another line used
to to signal "ready to receive a byte". I do remember that the
intrabyte transfer time for two bits was 10 clock cycles. That
doesn't include any of the byte setup time. We were loading
just over 50K in less than 15 seconds.
The real trick to fast disk routines without blanking the screen
was knowing not ask for a byte to be transfered from the disk
when the video chip was drawing every 8th scan line. In the C64,
the video chip causes a DMA at the end of every 8th scan line
to access video ram and get the information for the next 8 lines.
This tristates the 6510 for 40 clock cycles and no instructions
can be executed.
Just my $.02
--Doug
====================================================
Doug Coward dcoward(a)pressstart.com (work)
Sr. Software Eng. mranalog(a)home.com (home)
Press Start Inc. http://www.pressstart.com
Sunnyvale,CA
Curator
Analog Computer Museum and History Center
http://www.best.com/~dcoward/analog
====================================================
Since floppy drives no longer use optical sensors, using a mechanical feeler
instead, you may find that the write-lock tabs that you once used on 5-1/4"
drives work fine, so long as you apply them so they're tight. That way the
feeler will encounter resistance when it tries to feel the hole.
Dick
-----Original Message-----
From: Stephanie Ring <sring(a)uslink.net>
To: classiccmp(a)classiccmp.org <classiccmp(a)classiccmp.org>
Date: Thursday, March 16, 2000 9:00 PM
Subject: Floppy rehab
>
>From: "Stephanie Ring"
>sring(a)uslink.net
>
>
>I would like to know what material can
>be substituted for the black slide on
>3.5 floppies when these are missing,
>on the right hand top corner.
>
>
>
--- John Wilson <wilson(a)dbit.dbit.com> wrote:
> On Thu, Mar 16, 2000 at 07:36:53AM +0100, Maciej S Szymanski wrote:
> > I'm trying to put back in service PDP-11/05 used to controll aircraft
> > structural test sytem. I's equiped with DECcassete drive (it looks like
> > normal audio cassete).
> > Is there any replacement for them ? I mean using good audio casset or
> > so.
>
> Replacement for which, the media, or the whole drive?
>
> DEC claimed that you couldn't use regular audio cassettes with the TU60
> because they couldn't handle the high tension used by the drive. Sounds like
> it could be hype but you never know. I mean, what's the point of building a
> peripheral that uses regular audio cassettes, except that it *doesn't* use
> regular audio cassettes? Worst of both worlds.
AFAIK, it is _not_ a regular cassette but the drive mechanism is based on
regular cassette transport hardware. The media is coated for low friction
to extend media life and reduce head wear, among other things. One minor
feature of the cassettes themselves is a plastic flippy write-protect tab.
Not essential but a nice touch.
As has already been pointed out, the cassettes have a notch in the middle
of the top and there's a finger or a block or something at the corresponding
location on the drive preventing you from mounting an audio tape.
I used to use tapes by the crate on my PET way back when. A regular speed
tape drive mixed with cheap Rat-Shack tapes was a dangerous combination. I
wouldn't want to use consumer grade tapes with a high-performance mechanism.
It makes me think of the nickname of the TS-11 - the "Tape Stretcher 11",
maybe a "Tape Annihilator 60"? :-)
-ethan
=====
Even though my old e-mail address is no longer going to
vanish, please note my new public address: erd(a)iname.com
The original webpage address is still going away. The
permanent home is: http://penguincentral.com/
See http://ohio.voyager.net/ for details.
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