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FUJITSU F2MC-8L F202RA User Manual

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APPENDIX B Overview of the Instructions

Bit Direct Addressing

The addressing, which is indicated by dir:b in the instructions list, is used for accessing the area from

0000

H

to 00FF

H

on a per bit basis. In this addressing, the higher one byte of the address is 00

H

. Specify the

lower one byte with the operand; and the bit position in the specified address with the lower three bits of

the operation code.

Figure B.1-3 shows an example.

Figure B.1-3 Example of Bit Direct Addressing

Index addressing

The addressing, which is indicated by @IX(off in the instructions list, is used for accessing the entire area

of 64 KB. In this addressing, the contents of the first operand are signed and added to IX (index register).

Then the results are used as the address.

Figure B.1-4 shows an example.

Figure B.1-4 Example of Index Addressing

Pointer Addressing

The addressing, which is indicated by @EP in the instructions list, is used for accessing the entire area of

64 KB. In this addressing, the contents of EP (extra pointer) are used as the address.

Figure B.1-5 shows an example.

Figure B.1-5 Example of Pointer Addressing

SETB 34H : 2

0 0 3 4

H

7 6 5 4 3 2 1 0

X X X X X 1 X X

B

A

IX

MOVW A, @IX+5 AH

2 7 A 5

H

2 7 F F

H

1 2

H

2 8 0 0

H

3 4

H

1 2 3 4

H

2 7 A 5

H

M OVW A, @EP

1 2 3 4

H

A

1 2

H

3 4

H

2 7 A 6

H

2 7 A 5

H

EP

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