INSTRUCTION SET

S3C84E5/C84E9/P84E9

 

 

POPUD — Pop User Stack (Decrementing)

POPUD dst,src

Operation: dst src

IR IR – 1

This instruction is used for user-defined stacks in the register file. The contents of the register file location addressed by the user stack pointer are loaded into the destination. The user stack pointer is then decremented.

Flags: No flags are affected.

Format:

opc

src

dst

 

 

 

Bytes

Cycles

Opcode

Addr Mode

 

 

(Hex)

dst

src

3

8

92

R

IR

Example: Given: Register 00H = 42H (user stack pointer register), register 42H = 6FH, and register 02H = 70H:

POPUD

02H,@00H

Register 00H = 41H, register 02H = 6FH, register 42H =

 

 

6FH

 

02H If the general register 00H contains the value 42H and the register 42H the value 6FH, the statement "POPUD 02H,@00H" loads the contents of the register 42H into the destination register. The user stack pointer is then decremented by one, leaving the value 41H.

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Samsung S3C84E5 user manual Popud Pop User Stack Decrementing, Popud dst,src, 6FH