Hexadecimal Notation
A base-16 numbering system, used by programmers.
It uses the 16 digits:

1 2 3 4 5 6 7 8 9 a b c d
  TECH Help! shows hex numbers suffixed with "H".
  Assemblers and Debug require hex numbers
beginning with "a-f" to start with a leading 0.
TECH Help! does not follow this convention.