Ok, now we're cooking. I loaded up EDUSYSTEM 4K BASIC on my 8/E this
evening. The paper tape was part number DEC-08-ED10A-A-PB and it ran just
fine. When it starts it askes which functions to retain (sort of like Focal
does) and then gives you the READY prompt. My standard test of a FOR next
loop with a PRINT statement in the middle ran just fine. However, I've got
_no_ documentation on this version of BASIC.
So if anyone has docs for this version of BASIC please let me know, thanks!
--Chuck
A 74123 is a retriggerable one-shot. For a given trigger transition, it
outputs a pulse of very approximately calculable duration and, should it get
another such trigger before it's done with its current pulse, will continue
that pulse until the predtermined pulse duration after the last such
trigger.
If you work for many companies and use one in a circuit, you will be fired
without further ado. That was SOP at Martin Marietta when I was there. I
even saw a manager back a guy into a corner to get him to save everyone the
embarassment and just quit.
There is no justification for using such a device with today's circuitry,
and the passives which make it stabile and predictable for practical use all
cost more than an equivalent precisely timed circuit.
Now watch the guys jump on this one because they got one to work once upon a
time. . .
Dick
-----Original Message-----
From: Bill Sudbrink <bill(a)chipware.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Saturday, July 10, 1999 2:49 PM
Subject: 74123... What's it do?
>I know that it is a "one-shot". What does that
>mean? The pinouts in the Chip Directory are
>no help. Several seem to be involved in the
>DEPOSIT logic on the IMSAI front panel.
>Also, I can't quite figure out what the logic
>table for the 74107 is trying to say.
>
>Thanks,
>Bill
> Well, I need some help with a SCSI tape drive!!
>
>ENVIRONMENT:
>Hardware: CQD 220/TM set both ways for W3-6
> W2 is out, standard CSR
> for tape
> TZK12-AA with jumpers OOOOOCCOOC
>Software: RT-11 V5.6
>
>BUT, when I try to do a COPY DU0:a.b MU0:a.b
>the system hangs without having written anything to MU0:
>When I try to do a BACKUP DU0:a.b MU0:a.b
>I get 2 error messages saying it couldn't do the BACKUP
>and quits, again without writing anything to MU0:
It would be nice if every tape drive reacted the same way to SCSI
commands, but this simply isn't the case. If you can try a different
SCSI controller (or even a different firmware revision) or a different
make of tape drive you'll probably have better luck.
The fact that you can do some very simple operations, but not some
more complicated operations, points to the problem being with certain
SCSI "position tape" commands. This isn't too surprising if (as
I'm assuming) this is a QIC cartridge drive - these often balk at
filemark and record skips, *especially* in reverse (which is something
that RT-11 will try to do for PIP-type operations for sure.)
>Please, any suggestions would be helpful.
I wish I could give you better advice than "it's hit and miss", but
that advice would be "only use devices that the company that made your
SCSI host adapter is willing to support", and this is often excessively
restrictive. I think the CMD's are only qualified against Exabytes
and some 4mm cart drives (at least they were when I bought my new CQD-440
most of a decade ago.)
--
Tim Shoppa Email: shoppa(a)trailing-edge.com
Trailing Edge Technology WWW: http://www.trailing-edge.com/
7328 Bradley Blvd Voice: 301-767-5917
Bethesda, MD, USA 20817 Fax: 301-767-5927
Note that when I substitute a TQ50/TK50, everything
is OK with respect to PIP and BUP.
Sincerely yours,
Jerome Fine
Well, I need some help with a SCSI tape drive!!
ENVIRONMENT:
Hardware: CQD 220/TM set both ways for W3-6
W2 is out, standard CSR
for tape
TZK12-AA with jumpers OOOOOCCOOC
= Parity, SCSI ID =4, TPWR
(at least the SCSI ID seems to be 4
since that is what the CQD 220/TM
says to use for MU0: and MU0: exists)
DC 6250
Software: RT-11 V5.6
Symptoms:
I can do both an INIT MU0:
and a RUN BUP MU0:/Z
followed by: DIR MU0: for the simple INIT
BACKUP/DIR MU0: for the RUN BUP MU0:/Z
and for either DUMP/TERM MU0:
I get the correct stuff (which is somewhat different)
in each case, so I know I am writing to the tape drive
which stops and starts and rewinds, etc. the appropriate
number of times for these successful operations.
At first I had a SCSI hard drive on the 50 pin cable as
well (not at end of daisy chain - i.e. in the middle)
which made no difference to MU0: and the SCSI
hard drive works just fine at 160334 with or without
the tape drive powered on or off.
BUT, when I try to do a COPY DU0:a.b MU0:a.b
the system hangs without having written anything to MU0:
When I try to do a BACKUP DU0:a.b MU0:a.b
I get 2 error messages saying it couldn't do the BACKUP
and quits, again without writing anything to MU0:
Note that when I substitute a TQ50/TK50, everything
is OK with respect to PIP and BUP.
Please, any suggestions would be helpful.
Sincerely yours,
Jerome Fine
Hi,
Does anyone need a NeXt color InkJet printer? I picked one up with some
other stuff and I don't need it. I guess it's pretty rare, I've seen a
bunch of NeXt LASER printers but I've never a NeXt color inkjet before. I
haven't tested it yet but it appears to be in fine condition. It uses the
same large ink cartridges that the Apple Color printer and some of the
Canon inkjets use and it has a SCSI interface. I'm open for trades on HP
stuff, S-100 stuff or anything else that looks interesting.
Joe
<
<I cant see aany identifier on the front of the drive. Thee labels on =
<the tapes which belong to it say TK50K is this enough? If not do I need =
<to open the box to look at the drive or are there distinguishing =
<features on the front which will give you an idea what drive it is?
Ok,
3100, mounted inside, then it's a TZK30 (same density as tk50).
The standard TK50 is full height and does not have three lights.
Likely the tape mount failed for some reason and now you'll have to manually
remove the tape.
Allison
<If you work for many companies and use one in a circuit, you will be fired
<without further ado. That was SOP at Martin Marietta when I was there. I
<even saw a manager back a guy into a corner to get him to save everyone th
<embarassment and just quit.
I would have gone for nothing less that total public humiliation.
<There is no justification for using such a device with today's circuitry,
MITS and IMSAI lived... and died by them. Myself they are ok for
non-critical timing. Unfortunately they were often used in critical
circuits, shame as there were parts that could be used for critical
timing but 7412X was not it!!
Allison
Hi Tony,
>....The only firmware on the disk controller board is the GCR
>encoder/decoder ROM and the microcontroller for the spindle
>motors. Neither of those would change for DS drives. And I'm
>not suprised that the boot ROM will boot a DS drive either.
Quite, IIRC when you're using DS drives the system treats each side of the disc
as a separate drive. So in a dual floppy machine you'd have drives A through D
(A/C and B/D) - under DOS anyway.
TTFN - Pete.
--
Hardware & Software Engineer. Sound Engineer.
Collector of Arcade Machines, Games Consoles & Obsolete Computers (esp DEC)
peter.pachla(a)virgin.net |
peter.pachla(a)vectrex.freeserve.co.uk |
peter.pachla(a)wintermute.free-online.co.uk | www.wintermute.free-online.co.uk
--
Hi Tony,
>> Have you ever found software which will drive the Centronics port
>>as GPIB?....
>No. It wouldn't be too hard to write it, though...
>
>All I/O is memory mapped. The base addresses for the 3 VIAs seem
>to be....
Aha....you have detailed technical docs on the machine???
I managed to get a "service manual" several years ago but it has nothing even
remotely useful in it.... :-(
>What I was really looking for, though, was sound _input_ software. The
>hardware is almost there (you'd need a preamplifier, that's all).
Sorry, I'd misunderstood what you meant.
>Aren't they 80 track? They certainly seemed to be. Which of course means
>the heads are different to the PC drive ones....
Augh, major brain fade....you're correct of course, the Sirius uses 80 track
drives (I'd been fiddling with an XT before I wrote the message).
What I think I was getting at....is that pretty much any 80 track drive from
that era should work, as long as you can remove the analogue/motor control
boards (which isn't usually possible on more modern drives).
TTFN - Pete.
--
Hardware & Software Engineer. Sound Engineer.
Collector of Arcade Machines, Games Consoles & Obsolete Computers (esp DEC)
peter.pachla(a)virgin.net |
peter.pachla(a)vectrex.freeserve.co.uk |
peter.pachla(a)wintermute.free-online.co.uk | www.wintermute.free-online.co.uk
--
