CHAPTER 4: INSTRUCTION SET

 

 

 

LDB %sp,%BA

Load BA reg. into stack pointer

1 cycle

Function: sp ← BA

 

 

Loads the content of the BA register into the stack pointer sp (SP1 or SP2).

Code:

Mnemonic

 

 

MSB

 

 

 

 

 

 

 

 

 

 

 

LSB

 

 

LDB %SP1,%BA

 

1

 

1

1

1

1

1

1

0

0

0

1

0

 

X

1FC4H, (1FC5H)

 

LDB %SP2,%BA

 

1

 

1

1

1

1

1

1

0

0

0

1

1

 

X

1FC6H, (1FC7H)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Flags:

E

 

I

C

 

Z

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

↓

 

–

–

 

–

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Mode:

Src: Register direct

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Dst: Register direct

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Extended addressing: Invalid

 

 

 

 

 

 

 

 

 

 

 

 

NOP

 

 

 

No operation

 

 

 

 

 

 

 

 

 

 

1 cycle

Function: No operation (PC ←

PC+1)

 

 

 

 

 

 

 

 

 

 

 

 

Expends 1 cycle without doing an operation that otherwise exerts an affect. The PC (program

 

counter) is incremented.

 

 

 

 

 

 

 

 

 

 

 

Code:

Mnemonic

 

 

MSB

 

 

 

 

 

 

 

LSB

 

NOP

 

 

 

1

1

1

1

1

1

1

1

1

1

1

1

X

1FFEH, (1FFFH)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Flags:

E

 

I

C

 

Z

 

 

 

 

 

 

 

 

 

 

 

 

 

 

↓

 

–

–

 

–

 

 

 

 

 

 

 

 

 

 

 

 

 

S1C63000 CORE CPU MANUAL

EPSON

111