R01UH0823EJ0100 Rev.1.00 Page 70 of 1823
Jul 31, 2019
RX23W Group 2. CPU
2.2 Register Set of the CPU
The RXv2 CPU has sixteen general-purpose registers, ten control registers, and two accumulator used for DSP
instructions.
Figure 2.1 Register Set of the CPU
Note 1. The stack pointer (SP) can be the interrupt stack pointer (ISP) or user stack pointer (USP), according to
the value of the U bit in the PSW.
R15
R14
R13
R12
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0 (SP)
*1
General-purpose register
b31 b0
DSP instruction register
b71 b0
ACC0 (Accumulator 0)
ACC1 (Accumulator 1)
USP (User stack pointer)
ISP (Interrupt stack pointer)
INTB (Interrupt table register)
PC (Program counter)
PSW (Processor status word)
BPC (Backup PC)
BPSW (Backup PSW)
FINTV (Fast interrupt vector register)
FPSW (Floating-point status word)
Control register
b31
b0
EXTB (Exception table register)