COPYR          Rabbit 4000 Instruction

Opcode	Instruction	Clocks	Operation
ED 88	COPYR	7+7i 2,2,2(2,3,2)i,1 ("i" is the number of bytes copied)	(PY) = (PX)    BC = BC - 1    PY = PY - 1    PX = PX - 1 repeat while {BC != 0}

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.