Dec %Sp; Ex %A,%B - Epson S1C63000 Core Cpu Manual

CHAPTER 4: INSTRUCTION SET

DEC %sp

Function: sp sp - 1
Decrements (-1) the content of the stack pointer sp (SP1 or SP2). This instruction does not
change the C flag regardless of the operation result.
Code:
Mnemonic
DEC %SP1
DEC %SP2
Flags: E I
–
Register direct
Mode:
Extended addressing: Invalid

EX %A,%B

Function: A B
Exchanges the contents of the A register and B register.
Code:
Mnemonic
EX %A,%B
E I
Flags:
–
Src: Register direct
Mode:
Dst: Register direct
Extended addressing: Invalid
90
Decrement stack pointer
MSB
1 1 1 1 1 1 1 1 0 0 0 0 0
1 1 1 1 1 1 1 1 0 0 1 0 0
C Z
–
Exchange A reg. and B reg.
MSB
1 1 1 1 1 1 1 1 1 0 1 1 1
C Z
– –
EPSON
LSB
1FE0H
1FE4H
LSB
1FF7H
S1C63000 CORE CPU MANUAL
1 cycle
1 cycle