Department of Computer Scien

ce and Information Engineering

National Cheng Kung University, TAIWAN

HANEL

LOOP AND JUMP INSTRUCTIONSConditional Jumps(cont’)

‰All conditional jumps are short jumps

¾The address of the target must within -128 to +127 bytes of the contents of PC

Jump if bit

＝1 and clear bit

JBC

Jump if bit

＝^0

JNB

Jump if bit

＝^1

JB

Jump if CY

＝^0

JNC

Jump if CY

＝^1

JC

Jump if byte

≠#data

CJNE reg,#data

Jump if A

≠byte

CJNE A,byte

Decrement and Jump if A

≠^0

DJNZ

Jump if A

≠^0

JNZ

Jump if A

＝^0

JZ

Actions

8051 conditional jump instructionsInstructions