RX610 Group
2. CPU
R01UH0032EJ0120 Rev.1.20
Page 59 of 1006
Feb 20, 2013
Notes: 1. In user mode, writing to the IPL[2:0], PM, U, and I bits by an MVTC or a POPC instruction is ignored.
2. In supervisor mode, writing to the PM bit by an MVTC or a POPC instruction is ignored, but writing to the other
bits is possible.
3. Switching from supervisor mode to user mode requires execution of an RTE instruction after having set the PM
bit in the PSW saved on the stack to 1 or executing an RTFI instruction after having set the PM bit in the BPSW
to 1.
4. The MVTIPL instruction is not supported in the RX610 Group. When writing to PSW.IPL[2:0], use the MVTC
instruction.
The processor status word (PSW) indicates results of instruction execution or the state of the CPU.
C Flag (Carry Flag)
This flag indicates whether a carry, borrow, or shift-out has occurred as the result of an operation.
Z Flag (Zero Flag)
This flag indicates that the result of an operation was 0.
S Flag (Sign Flag)
This flag indicates that the result of an operation was negative.
O Flag (Overflow Flag)
This flag indicates that an overflow occurred during an operation.
I Bit (Interrupt Enable)
This bit enables interrupt requests. When an exception is accepted, the value of this bit becomes 0.
U Bit (Stack Pointer Select)
This bit specifies the stack pointer as either the ISP or USP. When an exception request is accepted, this bit is set to 0.
When the processor mode is switched from supervisor mode to user mode, this bit is set to 1.
PM Bit (Processor Mode Select)
This bit specifies the processor mode. When an exception is accepted, the value of this bit becomes 0.
IPL[2:0] Bits (Processor Interrupt Priority Level)
The IPL[2:0] bits specify the processor interrupt priority level as one of eight levels from zero to seven, wherein priority
level zero is the lowest and priority level seven the highest. When the priority level of a requested interrupt is higher than
the processor interrupt priority level, the interrupt is enabled. Setting the IPL[2:0] bits to level seven (111b) disables all
interrupt requests. The IPL[2:0] bits are set to level seven (111b) when a non-maskable interrupt is generated. When
interrupts in general are generated, the bits are set to the priority levels of accepted interrupts.
Summary of Contents for RX600 Series
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