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Re: LS/HCT/etc. logic familes
On Tue, 11 Jul 2017 20:03:15 -0500, "Tim Williams"

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The equivalent would be to say that netlists are self-documenting.

Re: LS/HCT/etc. logic familes
On Tue, 11 Jul 2017 20:03:15 -0500, "Tim Williams"

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They are if sheet 1 is the block diagram and table of contents, and if
there's an associated design notes document.


--  

John Larkin         Highland Technology, Inc

lunatic fringe electronics  


Re: LS/HCT/etc. logic familes
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Oh why don't we just put a novel in there too!  :^)

Tim

--  
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Contract Design
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Re: LS/HCT/etc. logic familes
On Wed, 12 Jul 2017 04:34:34 -0500, "Tim Williams"

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The issue is, who can find, and make sense of, and modify, a design
two years after the author has vanished?

And when you open a file or look at a drawing, is your only possible
response "what the hell is this?"

I have a 71 (so far) page design notes doc on a current project.


--  

John Larkin         Highland Technology, Inc

lunatic fringe electronics  


Re: LS/HCT/etc. logic familes
On 2017-07-12 07:04, John Larkin wrote:
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Exactly. Some of my consulting assignments started because of that.  
There was no text document whatsoever, several ICs had become  
unobtanium, there were always numerous production issues and each unit  
had to be brought to life via magic incantations and skillful turning of  
a dozen trimpots, some simultaneously. Of course that alignment process  
wasn't documented either. So the first hours were spent on "Why was this  
done that way?", "Where is the firmware for U43?" ... "Oh dang, on an  
8-inch floppy" ... "How do we get that read out?".


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A large project I was involved in had about 3 feet shelf length of  
binders just for the hardware module specs, all full. In English we  
could have probably done it in 2-1/2 feet because the language is more  
efficient for tech stuff.

A mantra of the VP of R&D at my first employer, a former longtime army  
sergeant: "If you didn't document it, it didn't happen". That guy was a  
great manager.

--  
Regards, Joerg

http://www.analogconsultants.com/

Re: LS/HCT/etc. logic familes
wrote:

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Sometimes documenters can be _great_ jerks.  Recently had a go-round
with such a jerk who insisted on filing an "architecture" document
before I'd even had time to contemplate the specifications.

(I ended up offending his "sensibilities" >:-}
        
                                        ...Jim Thompson
--  
| James E.Thompson                                 |    mens     |
| Analog Innovations                               |     et      |
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Re: LS/HCT/etc. logic familes
On Wed, 12 Jul 2017 14:49:36 -0700, Jim Thompson

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We have one customer with a massively complex paperwork system. They
write a formal EPS (element performance specification) *before* they
talk to us about what's possible or best. Then when we see it and make
suggestions, there is a complex set of steps required to alter the
EPS, which requires filling out more forms. The forms are full of
buggy Word macros.


--  

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement  

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Re: LS/HCT/etc. logic familes
On Wed, 12 Jul 2017 16:38:07 -0700, John Larkin

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Sounds all too familiar... the paperwork takes 3-4X as much time as
the actual design :-(

My particular 'jerk' had a team of about 20 people to do a chip design
in 4 months... a chip design I would typically do, all by myself, in
the same 4 months (and FULLY worst-cased ;-)
        
                                        ...Jim Thompson
--  
| James E.Thompson                                 |    mens     |
| Analog Innovations                               |     et      |
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Re: LS/HCT/etc. logic familes
wrote:

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We document designs pretty well, in a design notes doc. Whiteboards
are titled and dated and photographed and saved in the project folder.

We even document breadboards. We have a folder on a server, J:\PROTOS,
and every breadboard or non-production test board gets its own Zxxx
part number and folder. That has schematic, whiteboard pics, proto
pix, PCB layout if there is one, test results, general notes. If we
learn anything about a part, that gets copied into the PDATA folder
for that part in our inventory database.

That stuff is great to keep.

It all gets backed up offsite, and if the media somehow goes obsolete,
we'll be doing backups for a lot of cycles on new media. Currently, we
use terabyte USB hard drives in write-once mode for offsite backups.




--  

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement  

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Re: LS/HCT/etc. logic familes
On Wed, 12 Jul 2017 16:33:52 -0700, John Larkin

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The coolest gadget I've ever seen was a whiteboard with a built-in
copier... when you were done scribbling, you pressed a button, and a
scanner bar passed over the whiteboard making a hard-copy file (PNG).

I have, many times, simply photographed a whiteboard, and inserted
that into the documentation.

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                                        ...Jim Thompson
--  
| James E.Thompson                                 |    mens     |
| Analog Innovations                               |     et      |
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Re: LS/HCT/etc. logic familes
On Wed, 12 Jul 2017 17:11:34 -0700, Jim Thompson

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I've seen several like that, all broken.

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We do that a lot. I photographed two whiteboards today. I sometimes
put a wb photo into a formal proposal; nobody seems to mind.

In my new office, I want really good whiteboard lighting and a
permanent-mounted webcam to snap the doodles.

(The office is going to be 24x24, 576 square feet. There are condos in
this town half that size.)




--  

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement  

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Re: LS/HCT/etc. logic familes
On Wed, 12 Jul 2017 17:11:34 -0700, Jim Thompson

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We had those in the conference rooms but they've all been taken out
(scrapped, I suppose).  It's easier to photograph a whiteboard with a
phone than to keep those things working (they're antiques).

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Sure, since everyone has one, phones are a lot easier.  Everyone can
make their own "notes".  


Re: LS/HCT/etc. logic familes
On 07/12/2017 05:40 PM, Joerg wrote:
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What's an 8-inch floppy?

That doesn't sound right at all.

Re: LS/HCT/etc. logic familes
Den torsdag den 13. juli 2017 kl. 02.07.10 UTC+2 skrev bitrex:
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https://upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Floppy_disk_2009_G1.jpg/1200px-Floppy_disk_2009_G1.jpg

Re: LS/HCT/etc. logic familes
On Wed, 12 Jul 2017 17:25:51 -0700 (PDT), Lasse Langwadt Christensen

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A few years back, noting that new versions of Wimpows weren't
supporting my legacy drives, I spent nearly a week copying from such
'legacy' media onto CD's and DVD's.

I have a stack of CD's and DVD's probably 18" high ;-)
        
                                        ...Jim Thompson
--  
| James E.Thompson                                 |    mens     |
| Analog Innovations                               |     et      |
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Re: LS/HCT/etc. logic familes
On 13/07/17 10:42, Jim Thompson wrote:
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What's a CD?

:)

Re: LS/HCT/etc. logic familes
Den torsdag den 13. juli 2017 kl. 02.43.06 UTC+2 skrev Jim Thompson:
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make sure to keep the old drives, I have a lot of CDs that are basically unreadable with anything but an old 4x drive        


Re: LS/HCT/etc. logic familes
On Wed, 12 Jul 2017 17:57:58 -0700 (PDT), Lasse Langwadt Christensen

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Just copy them to disk drives.  Keep a couple of copies.  Cheap!

Re: LS/HCT/etc. logic familes
On 07/12/2017 08:25 PM, Lasse Langwadt Christensen wrote:

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Ooooh, antiques! I've never seen the black one in real life. The red  
looks like what I used to play Oregon Trail on the Apple II in 2nd  
grade. The blue one is what I used to save assignments on in high  
school. I hung on to a few of those but they were all dead and  
bit-rotted last I tried to load anything off them, maybe around 2007

Re: LS/HCT/etc. logic familes
On 07/12/2017 08:43 PM, bitrex wrote:
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Good news is that I discovered my Nintendo Entertainment System "Dragon  
Warrior" game cartridge, which I last played around 1989 and had a CMOS  
memory with battery back-up for save states, still worked fine and had  
all my saved games from when I was about 12 years old available to play  
circa 2010

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