HP PCL/PJL reference (PCL 5 Printer Language) - Technical Reference Manual Part I

EN Define Symbol Set 10-7
First Code (UI)
Specifies the first character code in the set.
Last Code (UI)
The Last Code specifies the last character code in the set.
Together, the First Code through the Last Code identify the range of
character codes which map to the symbol index numbers (characters)
in the Symbol Map field.
Character Requirements (Array of UB) and
character requirement
This 8-byte field works in conjunction with the Character Complement
field in the header of a type 10 or 11 (unbound) font to determine the
compatibility of a symbol set with an unbound font. These two fields
identify the unbound fonts in the printer which contain the symbol
collections required to build a symbol set. Refer to “Unbound Scalable
Fonts” in Chapter 9, for a description of symbol collections and
unbound fonts.
Each bit in the field represents a specific collection. Setting a bit to 1
indicates that collection is required; setting the bit to 0 indicates that
collection is not required. (Bit 63 refers to the most significant bit of
the first byte, and bit 0 refers to the least significant bit of the eight
byte field.) The bit representations for the collections are shown
below. (The symbols for each collection are shown in Appendix D
of the PCL 5 Comparison Guide.)