Fujitsu 8FX User Manual

MB95630H Series
MN702-00009-2v0-E FUJITSU SEMICONDUCTOR LIMITED 11
CHAPTER 2 CPU
2.2 General-purpose Register
2.2 General-purpose Register
The general-purpose registers are a memory block in which each bank consists
of eight 8-bit registers. Up to 32 register banks can be used in total. The
register bank pointer (RP) is used to specify a register bank.
Register banks are useful for interrupt handling, vector call processing, and
sub-routine calls.
■ Configuration of General-purpose Register
• The general-purpose register is an 8-bit register and is located in a register bank in the
general-purpose register area (in RAM).
• Up to 32 banks can be used, each of which consists of eight registers (R0 to R7).
• The register bank pointer (RP) specifies the register bank currently being used and the lower
three bits of the op-code specify the general-purpose register 0 (R0) to the general-purpose
register 7 (R7).
Figure 2.2-1 shows the configuration of the register banks.
Figure 2.2-1 Configuration of Register Banks
For information on the general-purpose register area available on each product, see "■ AREAS
FOR SPECIFIC APPLICATIONS" in the device data sheet.
R0
R1
R2
R3
R4
R5
R6
R7
R0
R1
R2
R3
R4
R5
R6
R7
R0
R1
R2
R3
R4
R5
R6
R7
This address = 0x0100 + 8 × (RP)
32 banks
Memory area
0x1F8
Address 0x100
0x107
0x1FF
8 bits
The number of banks
available is restricted by
the available RAM size.
Bank 31
Bank 0

Fujitsu 8FX Specifications

General

Brand	Fujitsu
Model	8FX
Category	Computer Hardware
Language	English