Re: Software architecture using C for mid-range PIC.

Fevric J. Glandules wrote:
Hans-Bernhard Bröker wrote:
Fevric J. Glandules wrote:

The command set is fixed, and consists of about 30 ASCII triplets, and with any luck won't change too much.

Encoding a mere 30 commands as three-letter tokens is excessively redundant. I would strongly suggest to abbreviate further, to one or two letters. In the process you would both reduce your communication load and speed up the interpretation.

Meanwhile I've got a little less than 4K of RAM to play with <grin>.

You could still use a perfect hash function. That would basically amount to letting a machine condense your command set to single letters, in whichever way it liked.

Or you could combine all three letters into a single number, then switch() directly on that:

switch((u16)buf[0]<<16 + (u16)buf[1]<<8 + (u16)buf[2]<<0)

and let the compiler decide how to implement that most efficiently.
.

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