mc9s12xf512 Freescale Semiconductor, Inc, mc9s12xf512 Datasheet - Page 647

• Manufacturer Part Number: mc9s12xf512
• Description: S12x Microcontrollers 16-bit Automotive Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

14.8.1.13 Index Register plus Register Offset (IDR)
For load and store instructions (RS, RI) provides a variable offset in a register.
Examples:
14.8.1.14 Index Register plus Register Offset with Post-increment (IDR+)
[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:
14.8.1.15 Index Register plus Register Offset with Pre-decrement (–IDR)
[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:
14.8.2
14.8.2.1
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
Freescale Semiconductor
LDB
STW
LDB
STW
LDB
STW
LDL
LDW
LDB
STB
STW
Instruction Summary and Usage
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+)
MC9S12XF - Family Reference Manual, Rev.1.19
; 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.
Chapter 14 XGATE (S12XGATEV3)
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