Tom Handley wrote:
>
>    Don, I caught the `tail-end' of this but I would recommend doing a
> 1-1 crimp from the IDC to the DIP header. Adjust the pcb artwork on the
> IDC side so that the DIP is correct. When you start `flipping' wires
> around (ie: floppy disk cables), you will be sure to raise the cost and
> probably bring up reliablity problems.

Thanks Tom,
yes I wouldn't do anything but this.

If you missed the original post, it is the board at:
http://www.dontronics.com/dt106.html

The 40 pin edge connector will be multi purpose.
1) extend the pins out that don't appear on the Simm Bus.
2) give an alternative method of connection to the SimmStick.
3) act as a pod header for ***any*** 87x target board for load/go
operation.

Design by committee is never easy, but that's what I do when I invite
everyone to be involved in the design of a board.

After collating all the info that has been sent to us, a small group of
us sat down last night to drink as much of Don's beer as we possibly
could, and come up with a final board design.

The beer vanished to the last bottle, and I know we now have more
questions than answers, however I think we resolved the 40 pin thing.

Using an 877 footprint, we are going to make the 40 pin header and the
micro pinout to the same pattern.
You must ignore the pin numbering, as this doesn't line up, but it means
the 877 footprint appears as a .1" male header on the top edge of the
board.

Now, if you crimped a 1 for 1 ribbon cable with a 40 pin .6" header,
then you have a reversal problem, however if you solder the .1"
connector on the solder side of the board, the problem is solved.

As the board is also multi purpose, it's only when you want to use it as
a pod or emulator mode, that the connector needs to be mounted on the
solder side of the PCB.

As the PCB price is less than the price of the micro, we believe this is
the correct answer.

Don McKenzie  mailto:don@dontronics.com http://www.dontronics.com

Don's Download Dungeon:   http://www.dontronics.com/download.html
Australian Electronics Ring http://www.dontronics.com/aering.html
Win $500USD Cash. Micro design contest:  http://www.simmstick.com