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2.3 Programming Model
2.3.1 General-Purpose Registers
Registers R0 to R15 are general-purpose registers. They are used as accumulators for
various types of operation or memory access pointers.
■
General-Purpose Registers
Figure 2.3.3 shows the configuration of general-purpose registers.
Figure 2.3-3 Configuration of General-Purpose Registers
Of 16 registers, the following registers are provided for special applications, with some
instructions being enhanced.
• R13: Virtual accumulator
• R14: Frame pointer
• R15: Stack pointer
The initial values of R0 to R14 after resetting are undefined. The initial value of R15 is
00000000
H
(SSP value).
XXXX XXXX
H
XXXX XXXX
H
0000 0000
H
32 bits
[Initial value]
A
C
F
P
P
S
R 0
R 1
R 12
R 13
R 14
R 15