#!/usr/bin/perl -w

use strict;
# Some example "keywords" and how they should be displayed
my %kwfmt = (
  "RT" => "A",
  "PN" => "A",
  "SN" => "A",
  "AB" => "H",
  "CD" => "H",
  "B1" => "H",
);

# The kind of thing I will see in my file
my @record;
$record[0] = pack ("A2CA7", "RT", 7, "testing");
$record[1] = pack ("A2CH16", "CD", 8, "01020304FFDDEC19");

# Prints ASCII fields fine, truncates hex
for (my $i=0; $i<2; $i++) {
  my ($kw) = unpack("A2", $record[$i]);
  my ($rdata) = unpack("x2C/$kwfmt{$kw}", $record[$i]);
  print "$kw $rdata\n";
}