There are a lot of excellent contributions here. But I thought I could take a crack at this one

#! /usr/bin/perl

my $inst1 = "";
while(<DATA>) {
    chomp;
    if ( /inst1/ ) {
        my ( $hex, $etc ) = split "=";
        $inst1 = $hex;
    }
    elsif ( /inst2/ ) {
        my ( $hex, $etc ) = split "=";
        my $diff = ($inst1 - hex($hex)) & hex("0x0ffffff");
        printf "Diff = %6x hex, and %d decimal.\n", $diff, $diff;
    }
}


__DATA__
0x405d75=inst1 
0x405d7a=inst2 
0x4035f7=inst1 
0x4035f8=inst2 
0x4035f8=inst1 
0x4035fb=inst2 
0x4035fb=inst1 
0x4035fc=inst2 
0x4035fc=inst1 
0x4035fd=inst2 
0x405d7a=inst1 
0x405d81=inst2

[download]

The output is: 

C:\scripts>perl hex-and-decimal.pl
Diff = bfa286 hex, and 12558982 decimal.
Diff = bfca08 hex, and 12569096 decimal.
Diff = bfca05 hex, and 12569093 decimal.
Diff = bfca04 hex, and 12569092 decimal.
Diff = bfca03 hex, and 12569091 decimal.
Diff = bfa27f hex, and 12558975 decimal.

[download]

David.

In reply to Re: Subtract 2 hexadecimal numbers by dwm042
in thread Subtract 2 hexadecimal numbers by samd

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