Common Register Bank Prefix (Cmr) - Fujitsu MB90895 Series Hardware Manual

3.4.2

Common register bank prefix (CMR)

When the common register bank prefix (CMR) code precedes an instruction for
accessing a general-purpose register, the general-purpose register to be accessed by
the instruction can be changed to a common bank (register bank selected when the
register bank pointer (RP) is 0) at 000180
the register bank pointer (RP).
I Common Register Bank Prefix (CMR)
2
The F MC-16LX family provides common banks at "000180
commonly accessed by each task, regardless of the values of the register bank pointer (RP). Using the
common banks facilitates data exchange between two or more tasks.
Using the common banks facilitates data exchange between two or more tasks.
When the common register bank prefix (CMR) code precedes an instruction for accessing a general-
purpose register, the general-purpose register to be accessed by the instruction can be changed to a common
bank (register bank selected when the register bank pointer (RP) is 0) at 000180
the current value of the register bank pointer (RP).
Table 3.4-4 shows the instructions requiring care when using the common register bank prefix.
Table 3.4-4 Instructions Requiring Precaution When Using Bank Select Prefix (CMR)
Instruction Types
String instruction MOVS
SCEQ
FILS
Flag change instruction AND CCR,#imm8
OR CCR,#imm8
PS Return instruction POPW PS
ILM setting instruction MOV ILM,#imm8
H
Instruction
MOVSW Do not add the CMR code to string instructions.
SCWEQ
FILSW
The common register bank prefix code affects up to the next instruction.
The common register bank prefix code affects up to the next instruction.
The common register bank prefix code affects up to the next instruction.
to 00018F , regardless of the current value of
H
" to "00018F
H
Description
CHAPTER 3 CPU
" as register banks that can be
H
to 00018F , regardless of
H H
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