General-Purpose Registers - Fujitsu F2MC-8FX Hardware Manual

5.2

General-purpose Registers

The general-purpose registers are memory blocks consisting of eight 8-bit registers per
bank. A total of up to 32 register banks can be used. The register bank pointer (RP) is
used to specify the register bank.
Register banks are useful for interrupt handling, vector call processing, and subroutine
calls.
Configuration of General-purpose Registers
• The general-purpose registers are 8-bit registers and are located in register banks in the general-purpose
register area (in RAM).
• Up to 32 banks can be used, where each bank 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 general-purpose register 0 (R0) to 7 (R7).
Figure 5.2-1 shows the configuration of the register banks.
This address
For information on the general-purpose register area available on each model, see "3.2 Memory Map".
Figure 5.2-1 Configuration of Register Banks
+ 8 × (RP)
= 0100
H
Address 100
107
8bits
R0
R0
H
R1
R0
R1
R2
R1
R2
R3
R2
R3
R4
R3
R4
R5
R4
R5
R6
R5
R6
R7
R6
R7
H
R7
Bank 0
Memory area
1F8
H
1FF
H
Bank 31
32 banks
The number of banks
available is restricted by
the RAM capacity
available.
CHAPTER 5 CPU
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