B.2 addressing, Addressing, B.2 "a – FUJITSU Semiconductor Controller MB89950/950A User Manual
Page 283: The f
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APPENDIX B Overview of Instructions
B.2
Addressing
The F
2
MC-8L has the following ten addressing modes:
• Direct addressing
• Extended addressing
• Bit direct addressing
• Index addressing
• Pointer addressing
• General-purpose register addressing
• Immediate addressing
• Vector addressing
• Relative addressing
• Inherent addressing
■ Explanation of addressing
●
Direct addressing
Direct addressing is indicated by dir in the instruction list. This addressing is used to access the area
between 0000
H
and 00FF
H
. In this addressing mode, the higher byte of the address is 00
H
and the lower
byte is specified by the operand. Figure B.2-1 "Example of direct addressing" shows an example.
Figure B.2-1 Example of direct addressing
●
Extended addressing
Extended addressing is indicated by ext in the instruction list. This addressing is used to access the entire
64-KB area. In this addressing mode, the first operand specifies the higher byte of the address, and the
second operand specifies the lower byte.
Figure B.2-2 "Example of Extended Addressing" shows an example.
Figure B.2-2 Example of extended addressing
MOV 12
H
, A
4 5
H
4 5
H
A
0 0 1 2
H
1 2 3 4
H
MOVW A, 1 2 3 4
H
5 6 7 8
H
A
5 6
H
7 8
H
1 2 3 5
H