On Tue, Nov 30, 1999 at 02:17:06PM -0700, Dwayne Reid wrote:

> This is the challenge:  how to tell which number is highest.  The records

Just subtract one from the other, and look at the result only (not the
carry flag). E.g. if you have two adjacent numbers 7 and 8, subtract
7 from 8, you get 1. So 8 is higher. Similarly, if you subtract FF from
0, you get 1, so 0 is higher.

unsigned char   buffer[BLEN];

        unsigned char   i, j;

        for(i = 0 ; i != BLEN-1 ; i++) {
                j = buffer[i+1]-buffer[i];
                if(j != 1)
                        break;
        }

        /* now i points to the most recent entry in the buffer */

This will also give a sensible result if the buffer is all
zeros.

Regards, Clyde

--
Clyde Smith-Stubbs               |            HI-TECH Software
Email: clyde@htsoft.com          |          Phone            Fax
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HI-TECH C: compiling the real world.