Branching Instructions in 8051

• Unconditional jumps: LJMP addr16 (long), AJMP addr11 (absolute page), SJMP rel (short relative).
• Conditional jumps: JC rel (if CY=1), JNC, JZ, JNZ, JB bit,rel, JNB, JBC (jump if bit set then clear), DJNZ direct/Reg,rel (decrement & jump not zero), CJNE A,direct,rel / A,#data,rel / Rn,#data,rel / @Ri,#data,rel (compare & jump if not equal).
• Calls/Returns: LCALL, ACALL, RET, RETI.
• Indirect: JMP @A+DPTR.

Examples:

CJNE A,#10H,NOT_EQ
DJNZ R2,LOOP
JB P1.0,SET
LJMP FAR