LEDs are very generic components. All of the ones that you are talking
about are almost totally interchangeable, except for the 12 volt one (which
is probably a low voltage one with a built-in resistor .... no LED truly
operates off 12 volts).
An LED is still a diode. In the wrong direction, it doesn't conduct, and it
also doesn't give off any light, but no harm is done. In the "forward"
direction, usually run from a 5 volt supply, it would burn out (basically it
would be a short-circuit) except that it will invariably have a current
limiting resistor in series with it. Since the actual voltage across the
LED is .7 to about 3 volts or so, depending on the LED, and the supply
voltage is almost invariably 5 volts, the current limiting resistor
determines the current drawn and the power consumed (and, as a consequence,
how bright the LED is). Some LEDs are significantly more efficient (give
off more light per milliwatt used) than others, the specs will tell you
that, but again, in most applications you don't care about the power
consumption (milliwatts), and the brightness is subjective.
Excluding odd LEDs (like your 12 volt model which, again, is probably a
low-voltage LED with the resistor built-in probably for automotive use), any
LED will work, although different ones will vary in brightness and power
consumption (if power consumption matters .... usually it does not). If you
get it backwards, it won't light, but no harm will be done.
On Thu, 20 Oct 2005, Ethan Dicks <ethan.dicks at gmail.com> wrote:
> On 10/21/05, charlesmorris at direcway.com <charlesmorris at direcway.com> wrote:
> > Currently I don't have any other input device aside from the programmer's panel
> > and the keyboard, so naturally I need something that can be booted from an
> > RL02...
>
> You may or may not have an RL boot PROM in your KM8AA, but if you
> don't, you can always key in the RL bootstrap by hand.
I'm not even sure they exist. Anyone have boot roms for RL?
> > Could I run OS/8? TSS/8? Many years ago I used to have access to a TTY timeshared to an 8/E running Edusystem 50 (TSS/8) and would like that "feel" again...
>
> Dunno about TSS/8 on an RL (probably no driver for anything newer than
> an RF08), but certainly OS/8. One caveat - there is a different
> driver for the RL01 and for the RL02. I myself have never used an
> RL02 on an 8/a. An expensive configuration for a DECmate I was an
> RL02, so I'm sure OS/78 supports it, but you might have to cherry-pick
> your OS/8 version to go with a larger disk.
Actually, any version of OS/8 will work fine. What you need is the device
driver. And yes, there are two different drivers, depending on RL01 or
RL02. Um, actually there are four different device drivers, since each
exists both for use as the system device, and not.
I'm using an RL02 with my PDP8, and have for ages.
A few things might need patches as well as having the device driver.
RESORC and PIP comes to mind. They have tables of device sizes, which
might not have the RL02 in there...
Johnny
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt at update.uu.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
An update to the comments of last week: I retrieved my source listing of
the linker for Panos last night, and buried in the middle of it was a
commented-out section for handling object files from Xenix-32000.
So I guess at some point Acorn was indeed looking at Xenix for that
platform. I do sort of have a vague recollection of some involvement
with Logica. I suspect this was one of those one-man projects where the
only Acorn person involved was the manager. Maybe Dave Lamkin, or his
boss whose name escapes me for now. (Mike someone?)
By the way the Panos linker is 3/4in thick fanfold and quite a bit to
scan. I guess I'll do it sometime but it's not a priority; I've been
having much more fun recently scanning Edinburgh University documents
detailing the operation of both the PDP9/15 systems, and the Interdata 74's.
In recent weeks I've scanned the sources of an operating system for
the Interdatas ("Legos") and a BIOS for an ICL 7502 remote job entry
terminal which Edinburgh University managed to turn into a serviceable
computer. Also the documentation for the High Level Assembler used
on both these systems. (We already had the source of the assemblers, just
no docs or predef files.)
The Edinburgh collection is getting quite impressive. We also have
recovered locally written operating systems for the PDP9 and PDP15,
two O/Ses for PDP11s, Perkin Elmer 32bit, 68000s and of course the
big one, EMAS for ICL29XX and IBM mainframe architectures of various
flavours.
( http://history.dcs.ed.ac.uk/ )
Graham
Steve Wrote:
>Message: 12
>Date: Fri, 21 Oct 2005 07:53:28 -0700 (PDT)
>From: steve <gkicomputers at yahoo.com>
>Subject: Re: Big dollars paid for Altair 8800 on Ebay
>To: "General Discussion: On-Topic and Off-Topic Posts"
> <cctalk at classiccmp.org>
>Message-ID: <20051021145329.54055.qmail at web51610.mail.yahoo.com>
>Content-Type: text/plain; charset=iso-8859-1
>
>I find interesting the big dollars that IBM manuals
>are going for (>$900)
>
>http://cgi6.ebay.com/ws/eBayISAPI.dll?ViewListedItems&userid=suetbandit&sor…
I wonder who dkdkk is? He bought almost all of the IBM stuff (modules and manuals) and plunked down over 16,800 US$. He must be re-selling to the government <grin>
Gary Fisher
Tristone Capital Inc.
This e-mail and any attachments may contain confidential and privileged information. If you are not the intended recipient, please notify the sender immediately by return e-mail, delete this e-mail and destroy any copies. Any dissemination or use of this information by a person other than the intended recipient is unauthorized and may be illegal. Unless otherwise stated, opinions expressed in this e-mail are those of the author and are not endorsed by the author's employer.
Hans,
You make excellent points!
I'd do the same thing as I'd be very interested in seeing what was on that hard drive and actually running the machine in it's final re-incarnation. But maybe I would put the new cards in an later serial number box for operating (like a nice Star Trek game or Supercalc) and put other original cards, PS, and motherboard in the serial number 3 case. But I only have one already later model modded 8800 and didn't have nine grand Canadian either!
(Now if it was an IMSAI, that would be another story....except for the nine grand!) <grin>
---- EDITED ORIGINAL MESSAGE BELOW-----
>From: "Hans Franke" <Hans.Franke at siemens.com>
>Subject: Re: Big dollars paid for Altair 8800 on Ebay
>To: "General Discussion: On-Topic and Off-Topic Posts"
> <cctalk at classiccmp.org>
>Message-ID: <43591700.32111.10A59295 at localhost>
>Content-Type: text/plain; charset=US-ASCII
>
>Now, regarding your implication, yes, a nice like new car has it's value,
>but then again, a special sub serie might even catch a higher price when
>not shiny, and then there are modifications. Thing of a Shelby GT with
>added race trim. that would definitly catch a better price than a regular
>(already expensive) Shelby GT.
>
>Now, the above Altair could be compared again to a hot-rodded Model T.
>Lager engine (Z80) added high performace stuff (Hard Disk) and so on.
>Such a Car has a value in itself, and restoreing it to a factory like
>version should be considered vandalism.
>
>> I suppose the buyer is going to restore the original MITS cards as it was
>> first available, or is he going to keep it intact as it was sold to him?
>> It would be interesting (to me) to know peoples collecting philosophies
>> about that.
>
>Well, tough question. As for myself, I guess I would keep it the way
>it is right now. THe usage, the add ons _and_ the fact that it's ser#3
>add together for a very unique exhibition piece. 'Restoring' it would
>take away the life and history.
>
>Don't get me wrong, this isn't a 'do not touch' thing, unlike some
>weired car collectors, who buy cars and let them rust on purpose, I
>would go ahead and restore (if needed) the Altair to its last working
>condition. Make it show room able, but don't take away it's history.
>
>If the original cards where available with the unit, I wouldn't put
>them back in, but rather use as part of a proposed displa, maybe
>mounted on a wall behind the unit.
>
>Gruss
>H.
>--
>VCF Europa 7.0 am 29/30.April und 01.Mai 2006 in Muenchen
>http://www.vcfe.org/
Gary Fisher
Tristone Capital Inc.
This e-mail and any attachments may contain confidential and privileged information. If you are not the intended recipient, please notify the sender immediately by return e-mail, delete this e-mail and destroy any copies. Any dissemination or use of this information by a person other than the intended recipient is unauthorized and may be illegal. Unless otherwise stated, opinions expressed in this e-mail are those of the author and are not endorsed by the author's employer.
Hi
You shouldn't plug a LED into a curcuit backwards that
can supply more than about 8 volts someplace. LED's
zener at about 8 to 10 volts and the power
dissipated is much higher when it zeners, even with
a limiting resistor.
If you get the RS ones that are individually wrapped,
they usually have the polarity marked on the back of
the package. You should be able to check the polarity
with a meter by measuring the voltage from the unit.
Just match the polarities.
Dwight
>From: "Bradley Slavik" <fire at dls.net>
>
>I believe that all these LEDs are on ISA or EISA cards, circa 1987.
>
>Let me be more specific now that I have gone to radio shack.
>
>In 5mm red LEDs they have
>
>12volt, 2.6v, 1.8v
>
>Here are web pages:
>
>http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=276-2
>09
>?
>
>5mm Red LED
>$1.29 ?????Brand: RadioShack
>Catalog #: 276-209 ?????Model: 276-209
>
>
>Availability On-line: In-stock In Store: Check availability
>Phone: In-stock 1-800-THE-SHACK (1-800-843-7422)
>(Pricing and availability may vary outside the contiguous 48 United States.)
>Typical MCD is 1.5. Typical wavelength is 697mm. Size is T-1-3/4 or 5mm. Red
>lens color. Viewing angle is 36?. 10mA (max). Typical Voltage is 2.0, with a
>maximum voltage of 12.0V. Comes as package of 1.
>
>http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=276-0
>41
>
>5mm Red LED
>$1.29 ?????Brand: RadioShack
>Catalog #: 276-041 ?????Model: 276-041
>
>
>Availability On-line: In-stock In Store: Check availability
>Phone: In-stock 1-800-THE-SHACK (1-800-843-7422)
>(Pricing and availability may vary outside the contiguous 48 United States.)
>Typical MCD is 10. Typical wavelength is 700mm. Size is T1 3/4 or 5mm. Red
>lens color. Viewing angle is 30?. Current is 28mA (max). Typical Voltage is
>2.25, with a maximum voltage of 2.6V. Comes as package of 2.
>
>276-330 which is 1.8v does not seem to have web page available.
>
>Should I just put in the 12v one? And turn around if I get it wrong? or
>use jumpers to test it before soldering?
>
>Bradley
>
>
>
>
>Subject: Re: RL01 drive select plug and power supply questions
> From: Paul Koning <pkoning at equallogic.com>
> Date: Fri, 21 Oct 2005 10:58:55 -0400
> To: cctalk at classiccmp.org
>
> Allison> Yes I do. However for a single user system the load is not
> Allison> an issue. If your running a timeshare system such as RSTS
> Allison> or RSX with more than one user then DHV11 sense as well.
>
>Not true. 9600 baud is 960 interrupts per second, on a character I/O
>device. That's a big number for a PDP-11. Output will be
>significantly less of a burden with a DH type output controller than
>with other types -- even for just one active terminal.
Depends somewhat on the OS. It dont know about you but most people
can't type much faster than 100WPM (less than 10 chars sec).
For RT11 it's mostly unimportant. For unix (the most sensitive
to interrupt loading you _may_ care as a single user).
> Allison> For most of my 11s four lines is the limit for what I can
> Allison> seem to keep busy. Figure a user terminal, LA100 Printer
> Allison> and serial line for modem or data line to another system. At
> Allison> the extreme I've run two terminals for OSs that support that
> Allison> but, I can only type on on at any instant. ;)
>
>Sure, if you're mostly doing editing, then the CPU burden of high
>speed output may not be obvious. If you had an LN03 or similar
>printer, you might see it more easily. An LA100, of course, isn't
>much of a problem because it is quite slow.
Actually printers are a bursty load (fill the buffer and go away)
and I've found that in practice the faster you fill the buffer
the better (high line rates or use a parallel interface).
Actually try this config.
11/23B
256kW ram
RL02
RX02 x2
DLV11j terminal lines at 9600
DUV11 running DDCMP (DECnet phaseIII at 19.2k)
LPV11 (modifiedto match dataproducts interface) with
LN01/LN01S 12ppm printer. Later the LN01S was
replaced with a DLV11 (same address) and LN03.
RSTS (later RSX)
3 users
Typical task load was BASIC (modeling program for reliability),
calc, Text editing (word-11) and edit and a cardfile database
written in BASIC. Also we had preLAT software for the 11 to
take local printing from the VAX.
Performance was good enough that we used that over the VAX
(line lengths limited us to 2400baud in our part of the mill).
That saved the VAX for email via the DUV link or direct. Later
the DLV11j was replaced with a DHV and there was no noticeable
performace improvement. It was a strange config but it helped
us develop, sometimes test and support the up and comming printing
products. We later moved to a VAX750 and found it not much faster
as a user perception.
One of the strong points of the -11 is it's interrupt performance
compared to a lot of other machines. Not to say there wasn't a
point where the loading wasn't noticable just took a bit to get
there. The users noticed the modeling program the most as it was
heavy on the calculations, more ram and an 11/73 would have helped.
Allison
>
>Subject: Re: Wondering which OS to use (PDP-8/A)
> From: Johnny Billquist <bqt at Update.UU.SE>
> Date: Fri, 21 Oct 2005 13:06:20 +0200 (CEST)
> To: cctalk at classiccmp.org
>
>On Thu, 20 Oct 2005, Ethan Dicks <ethan.dicks at gmail.com> wrote:
>
>> On 10/21/05, charlesmorris at direcway.com <charlesmorris at direcway.com> wrote:
>> > Currently I don't have any other input device aside from the programmer's panel
>> > and the keyboard, so naturally I need something that can be booted from an
>> > RL02...
>>
>> You may or may not have an RL boot PROM in your KM8AA, but if you
>> don't, you can always key in the RL bootstrap by hand.
>
>I'm not even sure they exist. Anyone have boot roms for RL?
There must be as DEC sold 8As and RL02s as multi user WPS systems
(wps200 comes to mind).
No idea what the underlying OS for WPS was.
Allison
On Thu, 20 Oct 2005, Allison <ajp166 at bellatlantic.net> wrote:
> >Subject: Re: RL01 drive select plug and power supply questions
> > From: David Betz <dbetz at xlisper.mv.com>
> > Date: Thu, 20 Oct 2005 18:26:02 -0400
> > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
> >
> >Thanks for your reply. I guess I'm okay with power even if I leave in
> >the DHV11 as it seems my BA11-N has been upgraded to a H7861 power
>
> Unless you need the IO I'd pull it anyway. The system will run cooler
> and I doubt you have need for the lines. DHV11 is a MUX and you need
> the chassis kit to break out all the serial lines. Most OSs for PDP11
> don't use it (system build time option) and the DLV11J is easier to use
> and program. The DHV11 cannot be used for a console either.
I think I'll slightly disagree with you here.
While all you say is essentially true, the DLV11 is a tremendour burden on
the system compared to the DHV11. So if you actually want to run serial
connections to a machine, keep the DHV11, and don't use the console more
than absolutely neccesary.
Big difference between DMA and interrupts you know...
Johnny
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt at update.uu.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
