Identifier selection

A data processing apparatus configured to select 2M selected identifiers within a possible range of up to 2N identifiers, where M≦N, said data processing apparatus comprising:

• selection storage means for storing N+1 identifier selection bits, wherein a position of a marker bit in said N+1 identifier selection bits determines M;
• and
• identifier selection means for determining said 2M selected identifiers,
• wherein said 2M selected identifiers are defined by a base identifier and 2m−1 identifiers incrementally following said base identifier,
• wherein N−M bits of said N+1 identifier selection bits form N−M most significant bits of said base identifier, and M trailing zeroes form M least significant bits of said base identifier.

A method of selecting 2M selected identifiers within a possible range of up to 2N identifiers, where M≦N, said method comprising the steps of:

• providing N+1 identifier selection bits;
• setting a marker bit at a position in said N+1 identifier selection bits to determine M;
• and
• reading said N+1 identifier selection bits,
• wherein said 2M selected identifiers are defined by a base identifier and 2m−1 identifiers incrementally following said base identifier,
• wherein N−M bits of said N+1 identifier selection bits form N−M most significant bits of said base identifier, and M trailing zeroes form M least significant bits of said base identifier, wherein said method steps are implemented on a data processor.