8051 JZ Instruction

Jump if Accumulator Zero

Instruction	JZ relative address
Function	Jump if Accumulator Zero
Bytes	2
Cycles	2
Encoding	0 1 1 0 0 0 0 0 A7...A0
Operation	PC = PC + 2 IF A = 0 PC = PC + relative address
Description	If all bits of the Accumulator are 0, JZ branches to the address indicated; otherwise, it proceeds with the next instruction. The branch destination is computed by adding the signed relative-displacement in the second instruction byte to the PC, after incrementing the PC twice. The Accumulator is not modified. No flags are affected.
Flags Affected	C AC F0 RS1 RS0 OV P
Example	The Accumulator originally contains 01H. The following instruction sequence, JZ LABEL1 DEC A JZ LABEL2 changes the Accumulator to 00H and causes program execution to continue at the instruction identified by the label LABEL2.
Bytes: Number of bytes required to encode the instruction. Cycles: Number of instruction cycles required to execute the instruction. Note that there are 12 oscillator cycles to one instruction cycle on a standard 8051. Encoding: Lists the byte encoding for the instruction. Operation: Lists, step-by-step, the operations performed by the instruction. Flags Affected: are highlighted in Bold

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Related topics:
8051 Program Branching Instructions   |   8051 ACALL Instruction   |   8051 LCALL Instruction   |   8051 RET Instruction   |   8051 RETI Instruction   |   8051 JMP Instruction   |   8051 AJMP Instruction   |   8051 LJMP Instruction   |   8051 SJMP Instruction   |   8051 JNZ Instruction   |   8051 CJNE Instruction   |   8051 DJNZ Instruction   |   8051 NOP Instruction

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List of topics: 8051

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