All this talk of Ultrix made me decide to give it a go. After wasting
time and then working out none of the machines I have here support
Ultrix, I decided Simh was the way to go. After a couple of hours of
messing about and checking google, I discovered that Ultrix installs
on RZ disks and Simh doesn't support them. Which is probably why the
cd has been sitting in a box for a couple of years.
About to give up I found a page which shows how to change the
installation program to support RA disks. If anyone wants to give it a
go :
http://minnie.tuhs.org/pipermail/tuhs/2004-November/001090.html
It says it works on 4.3, but it worked on my 4.5 disk. It's installing now.
Dan
>
>Subject: Re: removing parts from PCBs
> From: Chris M <chrism3667 at yahoo.com>
> Date: Mon, 14 Nov 2005 11:02:42 -0800 (PST)
> To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org>
>
>I don't know what a solder pot is exactly, but at one
Solder pot is a ceramic cup usually about 2" across and about 2" deep
with a heating element around it. Filled with solder and the usual
use is to tin stripped leads.
>point I was contemplating fabricating a sort of U
>shaped thing to bolt onto the end of a solder iron
>(albeit a hefty one). Either sheet brass or copper
>would suit the purpose. You can find that sort of
>stuph at many hobby shops and even hardware stores
>(look for a rack full of stuph with the name "K & S",
>sheets, tubing, etc.) You would need a different
>"thing" for each size chip you wanted to desolder. If
>the ic is known bad, you don't have to worry about
>cooking it, though you have to be careful with the
>lans on the circuit board.
I've done that, you really need a heavy heater to do
the job and it's still possible to cook the part and
or the board.
I've been stripping boards and TV chassis (back when
they were tube) for 40+ years.
Allison
>
>--- William Donzelli <aw288 at osfn.org> wrote:
>
>> > That is by far the best method and also excellent
>> for board you really
>> > don't want to cook (as in ones you fix).
>>
>> One of the tricks is to get a solder pot the right
>> size - just big enough
>> for a 40 pin DIP.
>>
>> William Donzelli
>> aw288 at osfn.org
>>
>>
>
>
>
>
>__________________________________
>Yahoo! FareChase: Search multiple travel sites in one click.
>http://farechase.yahoo.com
Sun still has them(patches for SunOS)- just a bit difficult to get at
http://access1.sun.com/patch.y2k/
will get you y2k and security patches back to "Solaris SPARC 1.0" as they call it
I'm running 4.1.3_U1 with all patches-not on a public network- is that O.K.? What bennies are in 4.1.4?
Hi Jos,
I fully agree with you. Building your own CPU is really an exciting project.
I took me more then 3 months to debug my 110 TTL CPU with
256 words of micro code of 48 bits.
See: http://www.anysystems.nl/hjs22.html for some pictures and the
reference card.
I build this CPU & IO unit in 1976. A liitle bit younger then the
Elektor machine :-). Do you still have the Elektor machine ?
Regards Henk Stegeman.
Netherlands
>
> What surprises me about the home-built computers from scratch is the
> lack
> of imagination when it comes to architecture. Most are basically
> one-address-cum-accumulator designs. It would seem that larger
> register
> files are much easier to build nowadays and would open up the door to
> some
> 2 and 3-address designs.
The reason is the effort it takes......
Ask anybody who actually made a CPU ( I myself did a 12 bit
TTL based, single address single accumulator machine).
The real effort is actually building and debugging the unit.
There is only so much time you have....
>
> I've always thought that 24 bits is a nice word size for a small
> computer.
Much too big to actually build in TTL.
In 1974 Elektor magazine started a series of DIY articles that described
an extensible ( 12 bit or 16 bit width ) three address, clockless
computer.
TTL based, with a shiftregister based memory. (6 or 8 512x2
shiftregisters .)
An expensive extra wasa 2102 based RAM.
The machine did hardware multiply and divide +
Instructions were build into the address map .i,e, address XX is the
adder, adress yy is a shift and so on..
The start of this series actually predates the Mark8 computer !
Jos Dreesen
>Date: Fri, 11 Nov 2005 21:03:39 -0800
>From: "Chuck Guzis" <cclist at sydex.com>
>On 11/11/2005 at 8:31 PM compoobah at valleyimplants.com wrote:
>
>Yes, I hold the board component-side down and flame it from above--a lot
>of components will simply drop out of the board once the solder has
>melted--do this out-of-doors as the fumes from the epoxy or phenolic can be
>pretty noxious. Keep the flame moving. Sometimes just tapping the board
>will cause quite a few components to to fall out. DIPs usually require a
>pair of needle-nosed pliers or small screwdriver to remove.
>
>Some invert the arrangement and do it component side up with the fame from
>below. I'm not convinced that one method is any better than the other.
>An old propane barbeque grill might also be another approach. Another
>might be to use a heat gun.
I use the heat gun approach. I have a Milwaukee heat gun I bought at
Home Depot with adjustable temperature from 100 - 1000 degrees F. I
use something between 600 and 900 depending on my application.
If I want to remove a component from a board and reuse the board,
(e.g. remove soldered down PROM for reprogramming) I cover the
surrounding components in modeling clay. This may or may not
provide any protection from heat, but it does keep them from blowing
away. The first time I tried desoldering with a heat gun, I found
that all the surface mount passives (resistors & caps) surrounding
the target chip were randomized.
For big surface mount chips I like to use Chip Quik desoldering
alloy, which will lower the melting point of the solder on the board.
If I preapply Chip Quik, I can usually use the 600F setting for a
minute or two to loosen a chip. I've successfully done this on chips
as large as 208 pin QFPs.
Jeff Walther
I got some interesting bits today :
For the 380z Sbas, bcpl (4 disks), txed, zasm, cp/m 2.2 and 1.4 and Wordstar.
For the Nimbus Windows 1.01 (Which I've never seen), write 2.0,
various version of RM basic and Msdos 3.05.
I'd like to see windows booted up the earliest version I've seen is
2.x (can't remember).
Dan
>
>Subject: Re: semi-homemade micro
> From: woodelf <bfranchuk at jetnet.ab.ca>
> Date: Sun, 13 Nov 2005 11:04:38 -0700
> To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org>
>
>compoobah at valleyimplants.com wrote:
>
>>All the talk about building a mini from TTL got me thinking about homebuild micros, and what one would look like if I decided to build one (been playing with my IMSAI, too, which probably accounts for some of it)
>>
>Woodelf mutters:
>The biggest thing I can think of is you only have two sizes of
>computer today ... 16 bits or 32 bits of addressing.
Uhm, what about 12bit[OS8 srt-8]? There are few othter word lenths
than those that are not unobtainium.
>You can only get the 16 machines easly and resonable source of a OS.
Explain that from your perspective.
>The 68000 yes still works best with 64k addressing.
>Oddly the only micocomputer chip I like ( other than the 6800/6809) is
>National Semiconductor's 16032 is another chip that you could never get.
T-11 regular instruction set of the PDP-11. Not too hard to find.
Z8001 and Z8002s I have a few of. Z280, theres an interesting varient
of Z80 with 24bit MMU that looks like the DEC PDP11 MMU (even I&D!).
So you have to be a bit more descriptive.
Allison
From: "Chuck Guzis" <cclist at sydex.com>
On 11/14/2005 at 9:32 AM Dwight K. Elvey wrote:
>
>>> I've used peanut oil and a fry pan.
>
>
>
>That's downright scary--oil fires are nasty. And burns from oil that hot
>(I've had them from cooking) take a long time to heal.
>
>I've heard plenty about the big 30-quart propane-fired turkey fryers
>catching fire. I'm not so sure that I'd like to try your method, although
>it sounds interesting.
>
Indeed.
It's a clever idea, to be sure. For me, I've spent a good bit of time around everything from pans to very large buckets of boiling oil (wife is from New Orleans, I had to learn to keep her happy). Having had to triage a folks who weren't very experienced with oil (hint: your turkey, catfish, etc., should patted as dry as possible and MUST NOT STILL BE FROZEN...and the flame does not have to be maxed out), I would suggest sticking to heat guns and propane torches...at least when they burn you you can drop them and the worst of it stops. That's not true with oil..it really likes to stick to you and everyone else in the room. Messing around with hot oil if you're not an expert and there are other options is *not* my first choice.
YMMV...
Ken
P.S. - Watching someone drop a mostly frozen turkey in a vat of vigourously boiling peanut oil was a deeply disturbing experience...
I'm trying to get my RL02 working with my 8/A. Thanks Tim R. for
lending me a cable and terminator!
After finding a cold solder joint at the 8.2 MHz oscillator on the
RL8A, I thought I had it licked... the master clock would start
and stop if I pressed the oscillator's case. Now there is a steady
4.100136 MHz clock at the ribbon cable connector to the logic
board inside the drive. The power supply voltages on the board are
all within spec.
The problem is that not only does the Fault light still stay on,
the ready light (that illuminates the "Unit 0" plug) is also on.
According to the manuals this is not supposed to be possible since
the ready light only comes on when track 0 has been found, and the
heads are still locked home :( ???
The Load button has a very dim bulb, near end of life, but it does
light after the slow 15-second disk rotation. Pushing the Load
button does nothing (disk does not spin, Fault and Ready still
lit). Examination of the state machine lines shows that it is in
state 0 (Load Cart) but the input to it (DL5 ERR STATE COMD L) is
also asserted.
When turning the spindle by hand (from the access port underneath
the drive, with a cartridge in place) I can get a signal of at
most 0.2 volt p-p. This doesn't produce any pulses from pin 1 of
the LM393 amplifier. If I ground the "Raw Sec Pls Return" then I
can get a very noisy pulse train. When it's "inching" in startup
mode it is maybe 10 mv p-p which is way below the spec in the
manual and nothing comes out of the amp.
Is this sensor hall-effect or is it just a coil? DEC went out of
their way to run 5 volts to it, so I assume it's a transistorized
unit? More importantly, anyone got a spare? :)
thanks
Charles
