Because I want to learn feel free to improve the code and give hints what I could do better.

Use printf instead of print and sprintf. This:

print "ERROR: S3-Record with address " . sprintf("%08X", $next_address
+) . " is missing in input file!\n";
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is shorter (and perhaps clearer) as this:

printf "ERROR: S3-Record with address %08X is missing in input file!\n
+", $next_address;
[download]