Samsung SAM88RCRI S3C9442 Manual page 27

S3C9442/C9444/F9444/C9452/C9454/F9454
INDEXED ADDRESSING MODE (Concluded)
4-Bit Working
Register Address
Sample Instructions:
LDC
LDE
Figure 3-9. Indexed Addressing to Program or Data Memory with Long Offset
Program Memory
XL (OFFSET)
H
XL (OFFSET)
L
dst src
OPCODE
8-Bit
R4, #1000H[RR2]
R4, #1000H[RR2]
NEXT 3 Bits
Point to working
register pair
(1 of 8)
LSB Selects
+
16-Bit
Program Memory
16-Bit
; The values in the program address (RR2 + #1000H)
are loaded into register R4.
; Identical operation to LDC example, except that
external program memory is accessed.
ADDRESSING MODES
Register File
Register
Pair
or
Datamemory
Value used in
OPERAND
instruction
16-Bit
address
added to
offset
3-9