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G
Abbreviated direct addressing (dir)
Specify the eight low-order bits of a memory address explicitly in an operand. Address bits 8 to 15 are
specified by the direct page register (DPR). Address bits 16 to 23 are specified by the data bank register
(DTB).
Figure A.3-6 Example of abbreviated direct addressing (dir)
MOVW S;20H, A
Before execution
After execution
G
Direct addressing (addr16)
Specify the 16 low-order bits of a memory address explicitly in an operand. Address bits 16 to 23 are
specified by the data bank register (DTB). A prefix instruction for access space addressing is invalid for
this mode of addressing.
Figure A.3-7 Example of direct addressing (addr16)
MOVW A, 3B20H
Before execution
A
After execution
A
(This instruction writes the contents of the eight low-order bits of A in abbreviated
direct addressing mode.)
A
4 4 5 5
1 2 1 2
6 6
DTB
A
4 4 5 5
1 2 1 2
6 6
DTB
(This instruction reads data by direct addressing and stores it in A.)
2 0 2 0
A A B B
DTB
5 5
0 1 2 3
DTB
A A B B
5 5
Memory space
7 7
776620H
? ?
Memory space
7 7
776620H
1 2
Memory space
553B21H
0 1
553B20H
2 3
APPENDIX A Instructions
623
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