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CHAPTER 3 CPU
3.1.1 Specific-purpose Areas

In addition to the I/O area, the general-purpose register area and vector table area are

available as areas for specific applications.

General-purpose Register Area (Address: 0100H to 01FFH)
This area is used for 8-bit arithmetic operations and transfer. Supplementary registers are provided.
Since this area is allocated to a part of the RAM area, it can also be used as normal RAM.
When this area is used as a general-purpose register, it can be accessed faster using shorter instructions
by general-purpose register addressing.
For details, see Section "3.2.2 Register Bank Pointer (RP) " and Section "3.3 General-Purpose Registers ".
Vector Table Area (Address: FFC0H to FFFFH)
This area is used as vector tables of the vector call instructions, interrupts, and reset.
This area is allocated to the highest ranges of the ROM area, and the start address of the corresponding
processing routine is set to the address of each vector table.
Table 3.1-1 provides the reference addresses in the vector table that correspond to the vector instructions,
interrupts, and reset.
For details, see Section "3.4 Interrupts ", Section "3.5 Reset ", and "CALLV #vct" in APPENDIX "B.2
Special Instructions ".
Table 3.1-1 Vector Table (1/2)
Vector call instruction Address in the vector table
Upper digits Lower digits
CALLV #0 FFC0HFFC1H
CALLV #1 FFC2HFFC3H
CALLV #2 FFC4HFFC5H
CALLV #3 FFC6HFFC7H
CALLV #4 FFC8HFFC9H
CALLV #5 FFCAHFFCBH
CALLV #6 FFCCHFFCDH
CALLV #7 FFCEHFFCFH
IRQF FFDCHFFDDH
IRQE FFDEHFFDFH
IRQD FFE0HFFE1H
IRQC FFE2HFFE3H