General-Purpose Registers; Figure 2.3-3 Configuration Of General-Purpose Registers - Fujitsu MB91F109 FR30 Hardware Manual

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.
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.
00000000

Figure 2.3-3 Configuration of General-Purpose Registers

R 0
R 1
R 12
R 13
R 14
R 15
(SSP value).
H
32 bits
C
A
F
P
S
P
2.3 Programming Model
[Initial value]
XXXX XXXX
H
XXXX XXXX
H
0000 0000
H
The initial value of R15 is
35