mc9s12xd256 Freescale Semiconductor, Inc, mc9s12xd256 Datasheet - Page 212

• Manufacturer Part Number: mc9s12xd256
• Description: Hcs12x Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Chapter 6 XGATE (S12XGATEV2)
6.8.1.13
For load and store instructions (RS, RI) provides a variable offset in a register.
Examples:
6.8.1.14
[RS, RI+] provides a variable offset in a register, which is incremented after accessing the memory. In case
of a byte access the index register will be incremented by one. In case of a word access it will be
incremented by two.
Examples:
6.8.1.15
[RS, -RI] provides a variable offset in a register, which is decremented before accessing the memory. In
case of a byte access the index register will be decremented by one. In case of a word access it will be
decremented by two.
Examples:
6.8.2
6.8.2.1
Any register can be loaded either with an immediate or from the address space using indexed addressing
modes.
The same set of modes is available for the store instructions
212
LDB
STW
LDB
STW
LDB
STW
LDL
LDW
LDB
STB
STW
Instruction Summary and Usage
Index Register plus Register Offset (IDR)
Index Register plus Register Offset with Post-increment (IDR+)
Index Register plus Register Offset with Pre-decrement (–IDR)
Load & Store Instructions
R4,(R1,R2)
R4,(R1,R2)
R4,(R1,R2+)
R4,(R1,R2+)
R4,(R1,-R2)
R4,(R1,-R2)
RD,#IMM8
RD,(RB,RI)
RD,(RB, RI+)
RS,(RB, RI)
RS,(RB, RI+)
MC9S12XDP512 Data Sheet, Rev. 2.17
; loads a byte from R1+R2 into R4
; stores R4 as a word to R1+R2
; loads a byte from R1+R2 into R4, R2+=1
; stores R4 as a word to R1+R2, R2+=2
; R2 -=1, loads a byte from R1+R2 into R4
; R2 -=2, stores R4 as a word to R1+R2
; loads an immediate 8 bit value to the lower byte of RD
; loads data using RB+RI as effective address
; loads data using RB+RI as effective address
; followed by an increment of RI depending on
; the size of the operation
; stores data using RB+RI as effective address
; stores data using RB+RI as effective address
; followed by an increment of RI depending on
; the size of the operation.
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