I may be still in shock at grouping in unpack (new in 5.8?), but will this work for you? (Please excuse the clumsy dumping)
  $str = "\004ABC\003DE\002F";
  $fmt = "(C X /a)*";
  @z = unpack($fmt,$str);
  foreach $z (@z) {
    print "'", join("', '", map {ord} split(//,$z)),"'\n";
  }
returns 
'4', '65', '66', '67'
'3', '68', '69'
'2', '70'
So you could probably get your desired result with "(n XX /a)*" ?

--
I'm a pessimist about probabilities; I'm an optimist about possibilities.
Lewis Mumford

In reply to Re: Unpacking fixed length records by shenme
in thread Unpacking fixed length records by diotalevi

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