MB91401
31
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GENERAL PURPOSE REGISTERS
Registers R0 to R15 are general-purpose registers. The registers are used as the accumulator and memory
access pointers for CPU operations.
Of these 16 registers, the registers listed below are intended for special applications, for which some instructions
are enhanced.
R13: Virtual accumulator
R14: frame pointer
R15:Stack pointer
The initial values of R0 to R14 after a reset are indeterminate. R15 is initialized to 00000000
H (SSP value).
0000 0000H
AC
FP
R0
R1
R12
R13
R14
R15
SP
XXXX XXXX
H
XXXX XXXXH
32 bits
Initial Value:
Prelminary
2004.11.12