On Mar 19 2005, 11:19, GManuel \(GMC\) wrote:
> It must be able to somehow. I have used a light pen on a Commodore 64
with a
> Graphics Program called Picasso's Revenge and have drawn on the
screen with
> it even on a completely black background. Not sure how it does it
though.
It's just a question of sensitivity. The black portions of the screen
are rarely quite black, because the electron beam is not quite turned
off. Thus a suficciently sensitive lightpen can still detect the spot
as it scans past the pen's location.
--
Pete Peter Turnbull
Network Manager
University of York
Hi,
I finally got a VME Bus for me to start experimenting. I want to connect
this to my Ultrasparc 2 using my Performance Tech Sbus-to-VME controller.
Unfortunately, I am a total newbie when it comes to VME. I got a VERO-BICC
Vme chassis that apparently once held a Force CPU. There are a bunch of
connectors on the VME backplane itself. Also, how does one even set up
these guys? The chassis has 5 VME slots. I want to use the Performance
Tech as the master controlling the VME Bus? and connect 2 (or more)
transtech/inmos VME boards....
Thanks,
Ram
Here's a list of the docs that came with the INFO 2000 disk setup,
aka PerSci 277 double drive and 1070 disk controller.
I know most of this is already available online, but I can scan any
of it on request.
PERSCI 1070 INTELLIGENT FLOPPY DISK CONTROLLER 12 pg. glossy
by Robert A. Stevens
Reprint of an article from Sept 1977 /Interface Magazine/
AN ADVANCED DISC-BASED SYSTEM 4 pg. glossy
by Michael Busch and Dan Gaines
From same magazine issue
INFO 2000 DISK SYSTEM 8 pg. sales brochure
for Heathkit H8
Digital Group
All S-100 Computers
PerSci Mass Storage Systems - Specifications 2 pg. glossy
PerSci Model 70 Diskette Drive - Specifications "
PerSci Model 277 Dual Diskette Drive - Specifications "
USERS MANUAL
Intelligent Diskette Controller
Model 1070
~40 pg. April, 1978
PRODUCT SPECIFICATIONS
Intelligent Diskette Controller
Model 1070 22 pg. June, 1977
WESTERN DIGITAL MOS/LSI FD1771
APPLICATION NOTE FLOPPY DISK FORMATTER/CONTROLLER
20 pg. March, 1978
Installation and Maintenance Manual
Duak Diskette Drive
Model 277 44 pg. July 1977
Logic & Schematic Diagram
Diskette Drive
Models 270/272/277 31 pg. January, 1978
Product Specification
Diskette Drive
Model 277 24 pg. January, 1978
Installation and Maintenance Manual
Duak Diskette Drive
Model 70 Series 39 pg. October 1976
Product Specification
Diskette Drive
Model 70 24 pg. January 1977
Product Specification
Diskette Drive
Model 299B 36 pg. not dated
USERS MANUAL
Dual Density Controller
Model 1170 62 pg. March 1980
Doc
PerSci, Inc.
Product Price List 1 pg. November 18, 1977
I picked up a KJ Instruments Model 506 Disk Drive Analyzer. It's a tester
for MFM drives. On the front are the data and power connectors for a
standard MFM drive, plus knobs, switches, LED displays, etc. On the back
are two DB-25 connectors.
Has anyone got a manual by some remote chance? Has anyone ever used one
of these?
--
Sellam Ismail Vintage Computer Festival
------------------------------------------------------------------------------
International Man of Intrigue and Danger http://www.vintage.org
[ Old computing resources for business || Buy/Sell/Trade Vintage Computers ]
[ and academia at www.VintageTech.com || at http://marketplace.vintage.org ]
Ethan,
I wrote the post about the TI 9900 processor cards. What are the
dimensions of the cards, and how many pins? I have two ram boards that may
be similar to yours, perhaps a little older based on the RAM chip numbers
you list below (assuming smaller number means older). I have the details
of my TI 9900-related stuff on
http://vintagecomputer.net/ti/TI-990-101/readme.txt. Here is a URL of pdf
links to TI-related hardware http://computer-refuge.org/bitsavers/ti/ and
try http://www.mainbyte.com/ti99/ in the event that you have a card
originally from an expansion unit for a 99 4/a. If you can read Japanese,
this page appears to have some info as well
http://www.orchid.co.jp/computer/hardware/parts/tms9900.html
Bill
>I was going through the basement at my old place today and ran across
>some boards that I bought at Dayton a large number of years ago. They
>all seem to be RAM boards of one type or another, one marked "24K",
>the other "8K w/ECC", loaded with different amounts of TI4060 RAM
>chips (approx the same package dimensions as, say, 5101 SRAMs). I
>don't have a net connection there at the moment, and I didn't have my
>camera with me, or I'd have taken pictures to post, but I thought I'd
>start by asking if anyone knows of a repository of TI board pictures
>like some of the Qbus field guides that are out there. I could then
>do a little browsing to figure out what these are from.
>One guess is that these look like what I've been reading about on the
>list recently about the TI990(?). They look newer than the boards in
>my TI980, and a little larger than those.
>I also found what look to be like TI laptop parts - a couple of
>daughter cards that seem to be some kind of video controller, and more
>of a main board, but without a CPU.
>I have no particular use for them except as a source of parts. If
>these sound interesting to anyone here, I can do a little more digging
>and/or take down part numbers and take pictures.
>No CPU or I/O cards, sorry.
>-ethan
------------------------------
Does anyone know a true (not a homebrew hack) multitasking environment that
will run in 16K or less, preferably with available source?
I was looking at Mini-UNIX for the PDP-11 and that's something similar to
what I'm looking for, but I wondered what other alternatives there were. Any
architecture will do, but I'm particularly interested in minicomputer
architectures for this project (DG, DEC, IBM, etc., would all be appropriate).
Thanks for humouring my odd request ^^
--
---------------------------------- personal: http://www.armory.com/~spectre/ --
Cameron Kaiser, Floodgap Systems Ltd * So. Calif., USA * ckaiser at floodgap.com
-- The steady state of disks is full. -- Ken Thompson -------------------------
I was going through the basement at my old place today and ran across
some boards that I bought at Dayton a large number of years ago. They
all seem to be RAM boards of one type or another, one marked "24K",
the other "8K w/ECC", loaded with different amounts of TI4060 RAM
chips (approx the same package dimensions as, say, 5101 SRAMs). I
don't have a net connection there at the moment, and I didn't have my
camera with me, or I'd have taken pictures to post, but I thought I'd
start by asking if anyone knows of a repository of TI board pictures
like some of the Qbus field guides that are out there. I could then
do a little browsing to figure out what these are from.
One guess is that these look like what I've been reading about on the
list recently about the TI990(?). They look newer than the boards in
my TI980, and a little larger than those.
I also found what look to be like TI laptop parts - a couple of
daughter cards that seem to be some kind of video controller, and more
of a main board, but without a CPU.
I have no particular use for them except as a source of parts. If
these sound interesting to anyone here, I can do a little more digging
and/or take down part numbers and take pictures.
No CPU or I/O cards, sorry.
-ethan
Thanks Tony for the advice:
> Fuse still blows? Remove the diode between pin 6 of T2 and the -12V line
> and the diode between pin 4 of T2 and the V+ line (RH side of sheet 1 of
> my CPU board schematic). With those lifted, the supply is reduced to a
> simple 12V one driving no load.
I did so and the fuse held. I meassured the +12V line and it gave me
close to 12V (+11.98V). I also reconnected CR13 (the one at pin 6
of T2) and got the -12V and -5V supplies as well.
Unfortunately, when connecting the other diode (CR12, pin 4 of T2), the
fuse blows.
> I'd supsect (a) a short in one of the output regulators _and_ (b) a
> problem with the current sense circuit (round U31, LM311).
Any ideas on how to debug this?
Thanks
**vp
BTW I have another question related to another 9915 with PSU probs.
What would cause the -12V supply to produce only around -5V (i.e.
the volatages on either side of the 332 Ohm resistor are around
-5V (not equal, but close).
On Mar 18 2005, 10:07, Dwight K. Elvey wrote:
> >From: "vrs" <vrs at msn.com>
> >There, "run" caps are generally oil, and "start" caps are
> >generally electrolytic. The exception being the occasional
"start/run" cap,
> >whatever that is.
>
> I believe that refers to how it is used. During the start,
> it is connected to a high current coil but during run, is
> is connected to a high resistant one to create phase shift.
>
> >The original caps in the TU56 are high capacitance, and clearly
> >electrolytic. But they appear to be wired for continuous phase
shifting
> >duty. Hence some of the people on the list insisting that they are
"run"
> >caps, and that the beefier, more expensive "run" cap should be used.
>
> Most likely to make the motor run smoother, as though there
> were more phases to the AC.
Simplified explanation: In "capacitor-start, capacitor-run" motors,
which run from single-phase AC, there are two sets of coils. The coils
need to be fed with AC out of phase with each other to cause the motor
to rotate. The AC supply is fed directly to one set of coils, and
through the capacitors to produce the phase shift for the second set of
coils. To start the motor, you need lots of current and a big phase
shift, so the "start" capacitor in parallel with the "run" capacitor is
a high value. A centrifugal switch in the motor disconnects that once
it gets to some fraction of its nominal speed, and then only the "run"
capacitor is left in series with the second set of coils.
Capacitors passing AC have an impedance, analagous to resistance but
frequency dependant, so they dissipate energy proportional to their
impedance and the square of the current. The "start" capacitor is only
in circuit for a short time, so it doesn't need to be as robust as the
"run" capacitor, which will be dissipating energy all the time the
motor is running. Of course if the load on the motor is low, so is the
current, so the capacitors may not need to handle too much energy once
it's running normally.
--
Pete Peter Turnbull
Network Manager
University of York
