HD404318 Datasheet, PDF (14/66 Pages) Hitachi Semiconductor – 4-bit HMCS400-series microcomputer

HD404318 Series
ROM Addressing Modes
Direct Addressing Mode: A program can branch to any address in ROM memory space by executing the
JMPL, BRL, or CALL instruction.
Current Page Addressing Mode: A program can branch to any address in the current page (256 words
per page) by executing the BR instruction.
Zero-Page Addressing Mode: A program can branch to any subroutine located in the zero-page
subroutine area ($0000–$003F) by executing the CAL instruction.
Table Data Addressing Mode: A program can branch to an address determined by the contents of 4-bit
immediate data, the accumulator, and the B register by executing the TBR instruction.
1st
2nd
instruction word instruction word
9
3
09
0
Opcode
Operand
Opcode ⁹
5
0
Operand
13
Program counter
Direct Addressing
0
13
0
Program counter 0 0 0 0 0 0 0 0
Zero-Page Addressing
Opcode
97
0
Operand
Operand
9
3
Opcode
07
B
3
0
A
13
0
13
0
Program counter * * * * * *
Program counter 0 0
Current Page Addressing
Table Data Addressing
Figure 8 ROM Addressing Modes
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