Samsung S3C9454B User Manual page 44

S3C9454B/F9454B
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
XLH (OFFSET)
XLL (OFFSET)
dst src
OPCODE
LSB Selects
16-Bit
R4, #1000H[RR2]
R4, #1000H[RR2]
Register File
NEXT 3 Bits
Point to working
register pair
(1 of 8)
+
16-Bit
Program Memory
Datamemory
OPERAND
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
Pair
16-Bit
address
added to
offset
or
Value used in
instruction
3-9