(Sent with the tag this time. Bah)

Hi list,

My current project contains a simple RS232 interface and is to recognise
typed commands received from a host PC. These commands will be simple,
short text strings e.g. GAIN, INPUT1 etc. So essentially the problem is
that I need to take a short text string and see if it matches any of 30
(or so) text strings contained within program memory (stored using rom
const char[]="blah"; etc), and return an index number of the matched
string if there is a positive match.

The first - and most obvious - method I can think of by which to compare
a given string of characters with a set of tabulated strings is to just
start at the top of the table, compare the first characters, if no match
then move down to next string in table, compare first characters again,
if match then compare the next characters along, etc etc.

But this is a wheel that has already been invented over and over again
no doubt, and I was wondering if there is a more clever or established
method that someone could suggest I use.

I know one other way could be to take the checksum of the input string
and compare that with checksums of the strings in ROM which is a much
faster process, but this would result in other randomly typed character
combinations potentially causing a 'match' too, unless there is a more
clever way of doing it.

Or there is the hash process which I am vaguely familiar with, but I
don't know if this is what I need.

Code examples for possible solutions would be useful (C or ASM) but a
basic suggestion about what kind of method to use would be extremely
helpful too.

Thanks in advance,

Trevor.

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