> Is the pinout in one or the other tech reference actually completely 
> backwards? And no one has made loud note of that?

Yes.

>From my post, and previous posts on the same issue:
"The confusion stems from the fact that ... looking into the pin side male and 
female connectors are reversed..."
but
..."the DVI male pins are numbered the same as a female socket."

Not LOUD enough? ;-)

That's why I said "The bottom line is that regardless of numbering the M100 
cable has to connect pin 1 of the DIP plug to pin 1 of the 2x20 pin header".

ICs and DIP plug pin numbers are pretty well standard and dual-row headers 
usually have an arrow and a key denoting pin 1 so I thought that would be 
concise enough without going into the confusing details of the relative pin 
numbers. But if you insist:

FWIW the T102 and 200 BUS connector pinout also does not follow 'normal' usage 
for a female connector; compare the illustration on page B-2 (PDF p.64) in the 
T200 manual to this:



This pinout is generally accepted as the 'standard' and the connectors 
generally have an arrow beside pin 1, but not always:

https://electronics.stackexchange.com/questions/106426/standard-nomenclature-for-2-row-connector-numbering-schemes

The T102/200 cable is a good example because both ends are the same type of 
connector: Forget about pin numbers and male vs. female; your example of the 
/WR signal is on the DVI's 12th pin from the right opposite the key; on the 
T102 & T200 it is on the 12th pin from the left on the side with the key, which 
is why it has to be swapped. Which one is right and which one is wrong?

> "I consider myself to know nothing until I actually see it work in my own 
> hands, or at least see someone else's equally incontestable proof showing it 
> working?"

Well, I thought that the label on the picture "Original M100 cable; note pin 1 
connected to wire #1" would strongly suggest that this was the cable originally 
supplied with the DVI and you could probably take for granted that it does 
indeed work. And why would I post a picture of a cable using the other type of 
DIP plug and the required adapter if it didn't work?

Did you really need a picture of the DVI connected, reading a disk and 
displaying some text to be convinced?

I was admittedly a little miffed that after my (too?) lengthy explanations of 
why your original suggestion would probably not work and I took the trouble of 
digging out my DVI cables and even opening the DIP connectors to show the 
difference between the original and a homemade version you apparently ignored 
it all and when your cable predictably didn't work you assumed that it must be 
the DVI and not your cable. 

Why did I bother?

BTW, the reason for the 'probably' was that I couldn't tell for certain from 
the pictures that the connectors you linked to were the wrong type for a 
straight-through cable, but they sure looked like it.

OK; you're from Missouri and my explanations could have been clearer, but hey, 
as long as folks can get through the confusing posts and issues and know how to 
make a correct cable, all's well (but you should really correct the Wiki.. ;-)

m
-------------
----- Original Message ----- 
  From: Brian White 
  To: [email protected] 
  Sent: Thursday, October 26, 2017 9:11 PM
  Subject: Re: [M100] DVI cable






  On Oct 26, 2017 7:48 PM, "Mike Stein" <[email protected]> wrote:

    Nice write-up except for the obviously still incorrect first part.

    I really don't get why this is such an issue; the correct cable connects 
pin 1 at one end to pin 1 at the other end, end of story.

  How is it so simple when you have never seen an official/original cable, or 
even a known-good home-made one, nor even have a known-good DVI to ensure that 
the cable is the only variable in the system?

  I was about to say you didn't post anything as definitive or explicit as you 
suggest now, but I just re-read you first post in this thread and I have to 
admit you did describe a simple rule to follow, and you didn't say it as "I 
thought it was...", you declared it.


  Mostly I guess it's just that no one had said anything at all on the topic 
(recently, in response to Randy's question I mean) at the time I decided to 
start figuring out the answer from first principles, and had already started 
gathering clues and references and deductions by the time you said that, so to 
me it somehow didn't register as being any firmer than just another possible 
idea that might be right, but still needs to be verified. You didn't actually 
say something like "Here is my actual cable which I actually used last month, 
and here is it's pinout."

  On top of that, before making the straight-through cable, I actually made one 
with the twists, and it didn't boot.

  On top of that, do the tech references not say what I say they say? AD0 is on 
pin 3 on the M100 clear as day, and on pin 6 on the DVI clear as day. (and by 
using AD0, we eliminate the possibility that one side or the other starts 
counting from 1, they both have an AD0). I linked to all the references I 
pulled from, right to th pag numbers, and for convenience I copied the pinout 
diagrams into a single side by side picture right on that wiki page. I mean, 
how is it at all irrational to refer to the tech reference? They are all known 
to have an error or two scattered in them, but they are still largely a correct 
reference. Is the pinout in one or the other tech reference actually completely 
backwards? And no one has made loud note of that?

  Given that, how is it at all remarkable that I consider myself to know 
nothing until I actually see it work in my own hands, or at least see someone 
else's equally incontestable proof showing it working?

  -- 
  bkw

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