MC68HC708MP16 Datasheet, PDF (66/398 Pages) Freescale Semiconductor, Inc – Microcontrollers

Central Processor Unit (CPU)
6.4.2 Index Register (H:X)
The 16-bit index register allows indexed addressing of a 64-Kbyte
memory space. H is the upper byte of the index register, and X is the
lower byte. H:X is the concatenated 16-bit index register.
In the indexed addressing modes, the CPU uses the contents of the
index register to determine the conditional address of the operand.
Bit
Bit
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Read:
Write:
Reset: 0 0 0 0 0 0 0 0 X X X X X X X X
X = Indeterminate
Figure 6-3. Index Register (H:X)
The index register can serve also as a temporary data storage location.
Technical Data
66
Central Processor Unit (CPU)
MC68HC708MP16 — Rev. 3.1
Freescale Semiconductor