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IDET     Interrupt Detection     Rabbit 3000A/4000/5000 Instruction

Opcode	Instruction	Operation
5B	IDET	Performs "LD E,E" But if (EDMR && SU[0]) then the System Violation interrupt flag is set.

Clocks	8-Bit Access	16-Bit Unaligned	16-Bit Aligned
Rabbit 3000A/4000	2	n/a	n/a
Rabbit 5000

Flags				ALTD			IOI/IOE
S	Z	L/V	C	F	R	SP	S	D
-	-	-	-

Description

The IDET instruction asserts a System Mode Violation interrupt if System/User mode is enabled (which is done by writing to the Enable Dual Mode Register, EDMR) and the processor is currently in user mode.

Note that IDET has the same opcode value as the instruction "LD E,E" and actually executes that opcode as well as the behavior described above. If IDET is prefixed by ALTD, the instruction LD E',E is executed and the special System/User mode behavior does not occur.