Oh, a little more thoughts.

If every processor is actively watching the communications, it can detect
when an "ack" has been sent to the message originator, and follow it
immediately with it's own message, if it has something to send.

Token ring methodologies also work extremely well for this, especially when
you have a 9-bit capable USART such as is in a PIC or the MAX3100.

Andy

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Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
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