FUJITSU F2MCTM-16LX User Manual

Page 607

Advertising
background image

591

APPENDIX B Instructions

Accumulator indirect branch addressing (@A)

The address of the branch destination is the content (16 bits) of the low-order bytes (AL) of the

accumulator. It indicates the branch destination in the bank address space. Address bits 16 to 23 are

specified by the program bank register (PCB). For the Jump Context (JCTX) instruction, however, address

bits 16 to 23 are specified by the data bank register (DTB). This addressing is used for unconditional

branch instructions.

Figure B.4-11 Example of Accumulator Indirect Branch Addressing (@A)

Indirect specification branch addressing (@ear)

The address of the branch destination is the word data at the address indicated by ear.

Figure B.4-12 Example of Indirect Specification Branch Addressing (@ear)

JMP @A

6 6 7 7

A

3 B 2 0

6 1

3 C 2 0

PC

4 F

PCB

6 6 7 7

A

3 B 2 0

3 B 2 0

PC

4 F

PCB

4F3C20H

JMP @A

4F3B20H

Before execution

After execution

Memory space

(This instruction causes an unconditional branch by accumulator indirect branch
addressing.)

Next instruction

JMP @@RW0

0 8

3 C 2 0

PC

7 F 4 8

PW0

4 F

PCB

2 1

DTB

3 B 2 0

PC

7 F 4 8

PW0

4 F

PCB

2 1

DTB

4F3C21H

7 3

4F3C20H

3 B

217F49H

2 0

217F48H

JMP @@RW0

4F3B20H

Before execution

After execution

Memory space

(This instruction causes an unconditional branch by register indirect addressing.)

Next instruction

Advertising