|
MC9S08GB60 Datasheet, PDF (131/290 Pages) Motorola, Inc – Microcontrollers | |||
|
◁ |
Addressing Modes
8.4.5 Extended Addressing Mode (EXT)
In extended addressing mode, the full 16-bit address of the operand is located in the next two bytes of
program memory after the opcode (high byte ï¬rst).
8.4.6 Indexed Addressing Mode
Indexed addressing mode has seven variations including ï¬ve that use the 16-bit H:X index register pair and
two that use the stack pointer as the base reference.
8.4.6.1 Indexed, No Offset (IX)
This variation of indexed addressing uses the 16-bit value in the H:X index register pair as the address of
the operand needed to complete the instruction.
8.4.6.2 Indexed, No Offset with Post Increment (IX+)
This variation of indexed addressing uses the 16-bit value in the H:X index register pair as the address of
the operand needed to complete the instruction. The index register pair is then incremented
(H:X = H:X + $0001) after the operand has been fetched. This addressing mode is only used for MOV and
CBEQ instructions.
8.4.6.3 Indexed, 8-Bit Offset (IX1)
This variation of indexed addressing uses the 16-bit value in the H:X index register pair plus an unsigned
8-bit offset included in the instruction as the address of the operand needed to complete the instruction.
8.4.6.4 Indexed, 8-Bit Offset with Post Increment (IX1+)
This variation of indexed addressing uses the 16-bit value in the H:X index register pair plus an unsigned
8-bit offset included in the instruction as the address of the operand needed to complete the instruction.
The index register pair is then incremented (H:X = H:X + $0001) after the operand has been fetched. This
addressing mode is used only for the CBEQ instruction.
8.4.6.5 Indexed, 16-Bit Offset (IX2)
This variation of indexed addressing uses the 16-bit value in the H:X index register pair plus a 16-bit offset
included in the instruction as the address of the operand needed to complete the instruction.
8.4.6.6 SP-Relative, 8-Bit Offset (SP1)
This variation of indexed addressing uses the 16-bit value in the stack pointer (SP) plus an unsigned 8-bit
offset included in the instruction as the address of the operand needed to complete the instruction.
MC9S08GB/GT Data Sheet, Rev. 2.3
Freescale Semiconductor
131
|
▷ |