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FUJITSU F2MCTM-16LX User Manual

Page 600

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APPENDIX

I/O direct bit addressing (io:bp)

Specify bits in physical addresses 000000

H

to 0000FF

H

explicitly. Bit positions are indicated by ":bp",

where the larger number indicates the most significant bit (MSB) and the lower number indicates the least

significant bit (LSB).

Figure B.3-8 Example of I/O Direct Bit Addressing (io:bp)

Abbreviated direct bit addressing (dir:bp)

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). Bit positions are indicated by ":bp", where the larger number indicates the most significant bit

(MSB) and the lower number indicates the least significant bit (LSB).

Figure B.3-9 Example of Abbreviated Direct Bit Addressing (dir:bp)

Direct bit addressing (addr16:bp)

Specify arbitrary bits in 64K bytes explicitly. Address bits 16 to 23 are specified by the data bank register

(DTB). Bit positions are indicated by ":bp", where the larger number indicates the most significant bit

(MSB) and the lower number indicates the least significant bit (LSB).

Figure B.3-10 Example of Direct Bit Addressing (addr16:bp)

0 0

0 1

0000C1H

0000C1H

Before execution

After execution

SETB I:0C1H:0

Memory space

(This instruction sets bits by I/O direct bit addressing.)

SETB S:10H:0

5 5

DTB

5 5

0 0

0 1

DTB

6 6

DPR

6 6

DPR

556610H

556610H

Before execution

After execution

Memory space

Memory space

(This instruction sets bits by abbreviated direct bit addressing.)

SETB 2222H:0

5 5

DTB

5 5

0 0

0 1

DTB

552222H

552222H

Before execution

After execution

Memory space

Memory space

(This instruction sets bits by direct bit addressing.)