1 special areas, Special areas – FUJITSU Semiconductor Controller MB89950/950A User Manual
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CHAPTER 3 CPU
3.1.1
Special Areas
In addition to the I/O area, the special purpose areas in the memory space include the
general-purpose register area and the vector table area.
■ General-purpose register areas (addresses: 0100
H
to 01FF
H
)
•
Provides auxiliary registers for 8-bit arithmetic operation and transfer instructions.
•
Allocated to a region of the RAM area. Can also be used as normal RAM.
•
Using the area as general-purpose registers enables high-speed access by general-purpose register
addressing using short instructions.
Table 3.1-1 "General-purpose register areas" lists the areas in each device that can be used for general-
purpose registers.
See section 3.2.2 "Register Bank Pointer (RP)" and section 3.3 "General-purpose Registers" for details.
Table 3.1-1 General-purpose register areas
Part number
MB89951A
MB89953A
MB89P955/PV950
Number of banks
8
16
32
Address range
0100
H
to 013F
H
0100
H
to 017F
H
0100
H
to 01FF
H