>But the prospect of a 16F chip and 18F chip residing on the
>same box has me willing to change my vote under a few conditions:
>
>1) That both chips/sockets be of the 40 pin variety.
>
>2) That the entire system can in fact be operated with only a single chip
in
>   place.
>
>3) That both chips/sockets have equal access to the I/O facilites onboard.
>
>4) We still carry a separate ICSP interface.

Well what I liked about a single 40 pin socket, was that the 16F877, and the
18F452 (from my very quick perusal of the data sheets) appear to be pin
compatible. This would mean the one socket would serve them both. This then
serves your item 3 above.

My only preference here is that some form of patch area is provided for the
peripherals so that they can be swapped between ports, or to the breadboard
area, even if this takes the form of holes to allow a ribbon cable pin
header to be fitted, but the holes are connected together by tracks which
need cutting with a scalpel if one wishes to change the port the peripheral
is on.

I'm quite happy that a 16F877A be the provided processor, but some info
would seem to be needed for the novice end user who may be familiar with the
info on the web, but as I understand it there are subtle differences with
this chip, apart from the programming, but I have no experience with it, and
have not checked it out.

If a person wanted to have a second processor then they could provide
themselves with another socket on the breadboard area. I personally don't
think that a second socket should be provided per se. maybe I could bend a
little and figure that a set of holes for a socket and headers, with
necessary components like the crystal/resonator and reset pull up resistors
be provided, but not the components to populate them. They are for the end
user to source and fit if required.

The "programmer" processor should be soldered in, and not in a socket. I
wonder if it is possible to have "multiple" ICSP ports on it, one
permanently wired (through protection resistors) to the provided socket, and
a second one to a separate ICSP header which is used for the external
programming port. If a second processor socket is provided then an ICSP port
to that could also be provided. A software command switches between ports to
determine which one is active.

>The only one magic feature that I'd like to personally see embedded in the
>firmware is the ability of the onboard processor to clone itself. It would
>only have to be a single algorithm for a single part. I just feel that the
>part should be able to back itself up without having to download software
>to it. But I realize that yould take up some more program memory that could
>be allocated for development. I'm not married to it, but it is a thought.
>I just see it as a convenient way to backup the Designer's main processor.

Well if there is a "programmer" on the board, and a file of the destination
chip contents, as provided with the kit, then this is not an issue, surely.
Taken to the extreme though, if the "programmer" chip has multiple ICSP
ports on it, then perhaps a command could be provided to "copy port X to
port Y", hence providing the duplication function totally inside the
"programmer" chip.

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