All,
Thanks to the kindness of Richard Lynch, I now have the 8" drive cabinet
to go with my newly-repaired Xerox 820-II. The drive mechanisms were
non-functional, unfortunately, so I need to scrounge together something
>from my junk, err parts collection.
I cannot find anything definitive regarding compatibility. I thought
these machines could use DSDD drives (one site mentioned Shugart SA851s),
but that would be 1.2M of capacity and everything I've found on the web
indicates perhaps 1/2 of that.
Can anyone tell me what will work with the unit and what low-level format
it writes?
Steve
--
[snip]
>
> Hi! The S-100 backplane PCBs have arrived. Please contact me if
> interested in getting one. Thanks and have a nice day!
>
> Andrew Lynch
[AJL>]
Hi! I updated the N8VEM wiki with some pictures of the S-100 PCB and
construction so far.
http://n8vem-sbc.pbworks.com/browse/#view=ViewFolder¶m=S100
I've partially built one of the units for testing. I've gone as far as I can
go but some parts are on back order. What is missing is the power connector
(0.200" spaced headers male). My plan is to finish assembly and test the
active terminator section before installing the S-100 connectors.
Some people have been concerned about availability of the S-100 connectors
but they are plentiful and relatively cheap. At Mouser you can get EDAC
parts which should work for $5 each. You can also substitute wire wrap
connectors which sometimes can be found on eBay for $3 each. I test
installed but did not solder some wire wrap S-100 connectors and they should
work just fine.
Thanks and have a nice day!
Andrew Lynch
>
>Subject: Re: Transistors...
> From: "bfranchuk at jetnet.ab.ca" <bfranchuk at jetnet.ab.ca>
> Date: Tue, 28 Apr 2009 18:07:20 -0600
> To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org>
>
>Scanning wrote:
>> A friggin piece of wire has a gain of 1 !!!!
>umm .999999 :)
>> / steven
>
Voltage gain, Current gain, or power gain?
Common base transistor has current gain of .99999.. and voltage gain >1 as
well as power gain. Wire is .9999999.. for all those.
Allison
[snip]
>
> Thanks and have a nice day!
>
> Andrew Lynch
Great pictures! (Once I figured out that I had to use IE vs. Firefox.) I
had forgotten how huge those connectors are. It has been a very long time
since I worked on the unit that our personal computer club at Recognition
Equipment put together...
Charlie Carothers
--
-----REPLY-----
Hi! Thanks! My hope is that this S-100 backplane will be a successful
project and make available a tool that S-100 hobbyists can use to develop
new peripherals and/or test and repair the ones they already have. The
ideal persons for this prototype phase would be those with experience in
building home brew S-100 systems and can identify and resolve issues with
the backplane, suggest improvements, etc.
There is very little S-100 development going on anymore so there appears to
be a dearth of tools available such as backplanes, prototyping boards, power
supplies, etc. Some new parts are needed, I think, for even the most basic
repairs without using the legacy systems.
Thanks and have a nice day!
Andrew Lynch
I'm attempting a painful task of extracting logic from an image of a
NMOS die manufactured in 1984. Initially, I'm only going after a small
portion of logic from the chip. I have a block diagram which appears to
roughly match the chip layout, a pinout, and an overall description of
the logic.
I have very little clue what I'm actually doing, but I'm trying to fix
that. :)
I'd like to develop a library of images of NMOS logic cells -- and
perhaps using pattern matching later, try to automate the process.
Does anyone here happen to know this stuff well enough to say, "there's
a NOR", "there's an OR", "that's an inverter." etc?
Anyone know the types of books I should be looking at to get this type
of information? NMOS Chip fabrication? Much of what I've found talks
about the actual process, but they normally show side-views of layers.
I'm looking down on the chip through a few layers and need stuff from
that perspective.
I have a couple example shots here
http://www.techtravels.org/snippet.jpghttp://www.techtravels.org/snippet2.jpg
Keith
P.S. Yes, I know, I'm crazy.
>>
>> To answer the question of why you'd want easy to use software, that
>> push
>> really does come from the corporate world. My favorite example for
>> this
>
> My entire post was about differentiating "easy to use" v "easy to
> learn".
> The corporate push is for "easy to learn", since they don't want a
> training expense for the digital sweatshop.
> Apple's marketing pushes "easy to learn" while calling it "easy to
> use".
> "Easy to use" and "easy to learn" may occasionally overlap, but are
> NOT
> the same for those who are capable of learning.
>
> Conflation of the two phrases is detrimental to the well being of our
> species.
I agree with the confusion being bad. I do not agree with the rest.
Ease of learning is important if you only want to use a program a
couple of times. Ideally you do not want to learn anything, you want
to get a job done and move on and not have irrelevant facts hanging
around in your head for ever-more. Where the Mac UI really used to
score over DOS and old Windows programs is that you learned a
technique which would be valid in every Mac program you would ever
come across, and so was worth learning. It did not matter if the
application was word processing, CAD, 3D, spreadsheet, drawing,
painting, photo retouching, page layout, music composing, video
editing, disk utility or whatever, the techniques were the same.
I find it very hard to get users to read a manual these days. If
facilities are not visible they do not find them. I know most,
probably all, of the people on this list are not manual avoiders but
we are a small minority, to write application software today which
could only be used after reading a manual would almost be commercial
suicide. Quite a few of my users remark that it is so rare to have a
printed manual available these days (we mail it out to users who pay a
small amount for it). We sell mainly via download and also have a
physical product we sell through the Apple stores and elsewhere, but
it has to be a standardised box to fit their shelves, and the box is
too small to fit the printed manual in.
For programs to be used long term I think that user configurability is
the key. There is no point hiding facilities as it makes learning
harder in the first place but once users become experienced they will
know which facilities they use most and can assign them short cuts.
The software designer should not make permanent choices on these,
though an educated guess which can be overridden can save time. There
does need to be a host of features but without impeding ease of
learning, this can be very tricky and itself takes years of experience
by the designer.
Not that my opinion is worth any more than anyone else's.
Roger Holmes.
I just noticed that the total size of the Bitsavers archive seems
to have surpassed 100 Gigabytes in the past few days.
In historical storage units, that is 160000 miles, nearly one light
second, of paper tape.
That is 1.25 Billion punched cards. At about 143 cards to the inch,
those punced cards would make a stack 137 miles high. Production of that
many cards would require three major deciduous forests, which by my exchange
table is also the same as one ship's peanut.
That is 40000 RK05 carts. At about 10 pounds per cart, that's almost half
a million pounds of RK05's.
Great job, Al!
Tim.
>Message: 12
>Date: Fri, 1 May 2009 12:56:29 -0400
>From: "Steve Robertson" < steerex at ccvn.com >
>Subject: FS: HP keyboards
>Yo,
>I've got some original HP keyboards that need a new home. The models are as follows:
<snip>
>I'd like to get a couple of dollars ($10) each plus shipping if anyone is interested?
>They are located in western North Carolina.
>See ya,
>Steve Robertson
Since you want a couple of dollars each, the $10 must be in binary. :)
Bob
