INSTRUCTION SET S3C8245/P8245/C8249/P8249
6-66
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 RIR
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.