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COPYR          Rabbit 4000/5000 Instruction

Opcode	Instruction	Operation
ED 88	COPYR	(PY) = (PX)    BC = BC - 1    PY = PY - 1    PX = PX - 1 repeat while {BC != 0}

Clocks	8-Bit Access	16-Bit Unaligned	16-Bit Aligned
Rabbit 4000	n/a	7+7i1	n/a
Rabbit 5000	5+7i1	7+7i1	7+7i1

1 "i" is the number of bytes copied

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

Description

This is a physical address block copy operation. It copies the number of bytes specified in BC starting from the address in PX to the address in PY, decrementing PY and PX for each successive byte.

Putting a physical address in the index registers means that the memory management unit (MMU) is not used by this instruction. Also, interrupts are possible between loops.