On Tue, 11 Nov 1997, Rick Dickinson wrote:

> Fellow PIC-Listers,
>
> Based on the feedback I have received, it seems that a design like the
 following
>  would make the most sense:
>
> Port A
> ------
>   0 - Serial Data Out   <-- Serial Data Out to the world.
>   1 - Range Mode Out    <-- Tells the Ranging Unit (RU) what mode to use.
>   2 - Range Trigger Out <-- Triggers the RU when in one-shot mode.
>   3 - Data Valid In     <-- Input from RU signals that data is valid.
>   4 - Serial Data In    <-- Serial Data In from world. Using RA4 allows us
>                              to use TMR0 rollover to detect start bit.

Using these pin assignments is going to make life difficult for anyone
who wants to implement a full speed multimaster I^2 C bus interface...
But maybe few people want that?

John Hallam, AI Dept, Edinburgh University.