Re: Sharing memory

eromlignod wrote:
Hi guys:

I'm an ME and I have an application where I'd like to use two Basic
Stamp microcontrollers working together. One is the main processor
that runs the show and does calculations; the other is a dedicated
slave that constantly distributes a series of 16-bit numbers to
various devices in a continuous, timed loop. The first processor
calculates what these numbers are based on feedback sources.

The reason I use a dedicated second processor is that its stream of
numbers can't be interrupted...it has to provide a continuous series
of values on a clock. The problem is that I can't even interrupt it
long enough to pass numbers to it from the other processor without
messing up the sequence.

What I'd like to try (if possible) is to share the same memory between
the two MCU's. So the first Basic Stamp is calculating values and
storing them to memory and the second Basic Stamp is using them as if
they were in its own memory bank simply by referring to a value by
variable name (or address??...I don't know).

Is this possible and, if so, what would be a good way of going about
it? I'm also open to alternate suggestions to solve the problem
including using a different processor (I would like to avoid investing
in another development kit or chip burner if possible though).

Thanks for any help you can provide.

Don


Normally, I would implement a periodic update on a timer interrupt and make the interrupt a sufficiently high priority. If your timing is so tight that you can't do this as you seem to imply in your post, it would make a strong case for either your processor not being fast enough or your design methodology is highly inefficient.

I can understand why you would want to avoid the costs associated with different development kits, programmers, and the increased learning curve. However, you need to carefully weigh these costs versus those incurred by continuing to implement an inadequate or incorrect design.
.

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