Samsung 8-Bit CMOS Microcontroller, S3C9228/P9228 user manual POP Pop From Stack

S3C9228/P9228 SAM88RCRI INSTRUCTION SET

POP — Pop From Stack

POPdst

Operation: dst ¨ @SP

SP ¨ SP + 1

The contents of the location addressed by the stack pointer are loaded into the destination. The stack pointer is then incremented by one.

Flags: No flags affected.

Format:

opc dst

Bytes	Cycles	Opcode	Addr Mode
		(Hex)	dst
2	8	50	R
	8	51	IR

Examples: Given: Register 00H = 01H, register 01H = 1BH, SP (0D9H) = 0BBH, and stack register 0BBH = 55H:

POP	00H	→	Register 00H	=	55H, SP = 0BCH
POP	@00H	→	Register 00H	=	01H, register 01H = 55H, SP = 0BCH

In the first example, general register 00H contains the value 01H. The statement "POP 00H" loads the contents of location 0BBH (55H) into destination register 00H and then increments the stack pointer by one. Register 00H then contains the value 55H and the SP points to location 0BCH.

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