On Thu, Jul 08, 1999 at 08:01:37PM +1000, Don McKenzie wrote:
>
> I get a 40 pin male .6" crimp header cable, the type that plugs into a
> 40 pin socket.

Don,

Here's a diagram, pictured from from the top, so that you are
looking down at the split IDC skewers that grab the ribbon cable
connectors; I've offset them in the way that they'll line up
with the cable:

DIP Plug:
     40
1
     39
2
     38
  ...
     21
20

IDC Female Connector:

1
      2
3
      4
5
  ...
39
     40

Obviously, if you are looking up at the holes in the IDC connector,
or the pins in the DIP plug, it is reversed from these. Thus,
via the ribbon cable, you'll get:

IDC  DIP
 1 --- 40
 2 ---  1
 3 --- 39
 4 ---  2
   ...

39 --- 21
40 --- 20

Alternatively, if you turn the DIP plug 180 degrees, you could
have

 1 --- 20
 2 --- 21
 3 --- 19
 4 --- 22
   ...
39 ---  1
40 --- 40

Caveat: I used a 14-pin DIP plug and a 10-pin IDC connector
as a reference, but I'm fairly sure that the extrapolation
is correct.

Does this help?

--Bob

--
============================================================
Bob Drzyzgula                             It's not a problem
bob@drzyzgula.org                until something bad happens
============================================================