DS07-16301-4E Datasheet, PDF (22/99 Pages) Fujitsu Component Limited. – 32-bit RISC Microcontroller CMOS FR30 Series

MB91101/MB91101A
s GENERAL-PURPOSE REGISTERS
R0 to R15 are general-purpose registers embedded on the CPU. These registers functions as an accumulator
and a memory access pointer (field for indicating address).
• Register bank structure
32 bits
Initial value
R0
XXXX XXXXH
R1
:
:
:
:
:
:
:
R12
:
R13
AC (accumulator)
:
:
R14
FP (frame pointer)
XXXX XXXXH
R15
SP (stack pointer)
0000 0000H
Of the above 16 registers, following registers have special functions. To support the special functions, part of
the instruction set has been sophisticated to have enhanced functions.
R13: Virtual accumulator (AC)
R14: Frame pointer (FP)
R15: Stack pointer (SP)
Upon reset, values in R0 to R14 are not fixed. Value in R15 is initialized to be 0000 0000H (SSP value).
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