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Popui – Samsung S3F80JB User Manual

Page 193

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S3F80JB

INSTRUCTION SET

6-65

POPUI

Pop User Stack (Incrementing)

POPUI

dst,src

Operation: dst

← src

IR

← IR + 1

The POPUI 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 incremented.

Flags:

No flags are affected.

Format:

Bytes Cycles Opcode

(Hex)

Addr Mode

dst src

opc src dst

3 8 93 R

IR

Example:

Given: Register 00H = 01H and register 01H = 70H:

POPUI 02H,@00H

Register 00H = 02H, register 01H = 70H, register 02H = 70H

If general register 00H contains the value 01H and register 01H the value 70H, the statement
"POPUI 02H,@00H" loads the value 70H into the destination general register 02H. The user
stack pointer (register 00H) is then incremented by one, changing its value from 01H to 02H.