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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Talk to your friends online with Yahoo! Messenger.
http://im.yahoo.com
Hi
Another question.
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.
MAciek
<You rang a bell with the comment about other units using the same
<standard, a TI "Silent 700 ASR" data capture terminal is sitting in my
<storage shed somewhere----neat panel up above the keyboard with lots of
<lights and switches and 2 very fancy looking cassette transports. must
<use those same cassettes.
Same or similar. At one time I was doing cassettes for data storage
(ca 1975-76) and still have my Redactron drive and also MPI plus a few other
scraps.
There were two major schools on the drive, capstan driven (PHI deck) and
reel to reel drive. Obviously one was constant speed tape and the other
without elaborate electronics were constant data rate (more or less).
The tapes themselves were different length, formulations and even front
coatings. Compatable... barely from the same drive.
<> > DEC claimed that you couldn't use regular audio cassettes with the TU6
<> > because they couldn't handle the high tension used by the drive. Sound
<> > it could be hype but you never know. I mean, what's the point of build
<> > peripheral that uses regular audio cassettes, except that it *doesn't*
<> > regular audio cassettes? Worst of both worlds.
True, while they would work for a while eventually they stretch though
some audio tapes were thicker. Also most audiotapes had huge dropout
zones where the recorded level would drop significantly.
Also the saturation recording was nothing like audio recording in how the
head was driven or the read back signal. The closest thing we have now to
the recording technique used is floppies.
Allison
I wrote:;
>HPUX 9.1, released in 1995, replaced 9.03 and was the last release
>to support the 68K-based architecture in the 300 and 400 series.
I should have written: HPUX 9.10 (official name ;-) )
Best regards,
Carlos.
At 08:51 PM 03/16/2000 -0500, you wrote:
>What was the highest HP-UX version that the 300-series could handle? Was it
>around 7.0 or 8.0? I've got a 9000/375 with 7.(mumble) and am curious.
>
>The 9000/332's at my old job seem to handle the Y2K thing okay according to
>my wife who still works with them there. Their application is a fixed
>machine control/data crunching job running under Workstation Pascal 3.2
>(not HP-UX) so dates are somewhat a non-issue anyway.
>
>BTW, anybody got a WS Pascal 3.2 distribution and manuals available?
>
>Regards, Chris
After since the newspaper article about my collecting was printed in the paper I have been getting calls and emails everyday with someone wanting to give me something. Here's a short list of some of the items I have picked up:
1. Lisa II complete and working with manuals and tons of software.
2. complete Mac IIcx in the box with Apple monitor also in it's box.
3. Prototype scsi tape unit for Apple done by 3M with tapes loaded software. The guy wrote the firmware for these drives that gave a box full of Apple stuff.
4. Complete Mac Plus system
5. Lots of books and manuals. One really nice one is a special Promotional Edition of Inside Macintosh dated 15 March 1985. The pages are made of thin tissue paper and were given to programmers at this guy's shop which purchased a large number of Lisa from Apple early.
6. Several IBM PS/2 systems not yet 10 years old.
7. Several printers, ink jets and dot's.
I still have about 6 more systems and other items to pick up from various people that have called. Now if someone would just give me another warehouse to store this stuff in. Keep computing John
