Fujitsu F2MC-16LX Hardware Manual page 45

Addressing Types by Bank
The bank addressing specifies the bank for each space by five bank registers as shown below by dividing
the 16 Mbytes space into 256 of 64 Kbytes banks:
Program bank register (PCB)
Data bank register (DTB)
User stack bank register (USB)
System stack bank register (SSB)
Additional data bank register (ADB)
The 64 Kbytes bank specified by the PCB is called as the program (PC) space. This PC space contains
instruction codes, vector tables, and immediate value data, for example.
The bank of 64 Kbytes specified by DTB is called data (DT) space. This DT space contains write-enabled
data, internal and external resource control/data registers, etc.
The 64 Kbytes bank specified by USB or SSB is called as the stack (SP) space. This space is accessed
when a stack access occurs at executing the push or pop instruction or saving the interrupt register, etc. The
stack space to be accessed depends on the S flag value in the condition code register.
The 64 Kbytes bank specified by the ADB is called as the additional (AD) space. This AD space contains
the data overflowed from the DT space, etc.
As shown in Table 2.2-1, the default space used in each addressing mode is predefined to improve the
instruction code efficiency. To use a space other than default in an addressing mode, specify the prefix code
corresponding to the bank before specifying the instruction code. This allows you to access an arbitrary
bank space corresponding to the prefix code.
After the reset, the DTB, USB, SSB, and ADB are initialized to 00
specified by the reset vector. After the reset, each of the DT, SP, and AD spaces is allocated to the bank
00 (000000
H
Table 2.2-1 Default Spaces
Default Spaces
Program space
Data space
Stack space
Additional space
Figure 2.2-4 shows the example of the memory spaces of the divided register bank.
to 00FFFF ) and the PC space is allocated to the bank specified by the reset vector.
H H
Indirect PC and program access and branch instruction
Addressing mode using @RW0, @RW1, @RW4, and @RW5; @A, addr16, and dir
Addressing mode using PUSHW, POPW, @RW3, and @RW7
Addressing mode using @RW2, and @RW6
and the PCB is initialized to the value
H
Addressing mode
CHAPTER 2 CPU
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