Fujitsu MB90460 Series, Hardware Manual, Page: 661 / 739

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APPENDIX
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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 B.3-6 Example of Abbreviated Direct Addressing (dir)
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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 B.3-7 Example of Direct Addressing (addr16)
MOV S : 20H, A (This instruction writes the contents of the eight low-order bits of A in
abbreviated direct addressing mode.)
Before execution A 4 4 5 5 1 2 1 2 Memory space
DPR 6 6 DTB 7 7 776620
H
? ?
After execution A 4 4 5 5 1 2 1 2 Memory space
DPR 6 6 DTB 7 7 776620
H
1 2
MOVW A, 3B20H (This instruction reads data by direct addressing and stores it in A.)
Before execution A 2 0 2 0 A A B B DTB 5 5 Memory space
553B21
H
0 1
553B20
H
2 3
After execution A A A B B 0 1 2 3 DTB 5 5