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LLRET     Far Return     Rabbit 4000/5000 Instruction

Opcode	Instruction	Operation
ED 8B	LLRET	PClow = (SP) PChigh = (SP + 1) XPClow = (SP + 2) XPChigh = (SP + 3) SP = SP + 4

Clocks	8-Bit Access	16-Bit Unaligned	16-Bit Aligned
Rabbit 4000	14	n/a	n/a
Rabbit 5000	4	4	2

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

Description

The LLRET instruction is used to return from an LLCALL operation. It transfers execution from a subroutine to the calling program by popping PC and the XPC from the stack.

The low-order byte of PC is loaded with the data whose address is SP and the high-order byte of PC is loaded with the data whose address is SP+1. Then, the low-order byte of XPC is loaded with the data whose address is SP+2 and the high-order byte of XPC is loaded with the data whose address is SP+3. Finally, the value in SP is incremented by 4.