Program execution transfer instructions in 8086 microprocessor

MicroprocessorMicrocontroller8086

These instructions are used to transfer/branch the instructions during an execution. There are two types of branching instructions. The unconditional branch and conditional branch.

The Unconditional Program execution transfer instructions are as follows.

Opcode
Operand
Description
CALL
address
Used to call a procedure and save their return address to the stack.
RET
----
Used to return from the procedure to the main program.
JMP
address
Used to jump to the provided address to proceed to the next instruction.
LOOP
address
Used to loop a group of instructions until the condition satisfies, i.e., CX = 0

 

Now let us see the Conditional Program execution transfer instructions.

Opcode
Operand
Description
JC
address
Used to jump if carry flag CY = 1
JNC
address
Used to jump if no carry flag (CY = 0)
JE/JZ
address
Used to jump if equal/zero flag ZF = 1
JNE/JNZ
address
Used to jump if not equal/zero flag ZF = 0
JO
address
Used to jump if overflow flag OF = 1
JNO
address
Used to jump if no overflow flag OF = 0
JP/ JPE
address
Used to jump if parity/parity even PF = 1
JNP/ JPO
address
Used to jump if not parity/parity odd PF = 0
JS
address
Used to jump if sign flag SF = 1
JNS
address
Used to jump if not sign SF = 0
JA/ JNBE
address
Used to jump if above/not below/equal instruction satisfies.
JAE/ JNB
address
Used to jump if above/not below instruction satisfies.
JBE/ JNA
address
Used to jump if below/equal/ not above instruction satisfies.
JG/ JNLE
address
Used to jump if greater/not less than/equal instruction satisfies.
JGE/ JNL
address
Used to jump if greater than/equal/not less than instruction satisfies.
JL/ JNGE
address
Used to jump if less than/not greater than/equal instruction satisfies.
JLE/ JNG
address
Used to jump if less than/equal/if not greater than instruction satisfies.
JCXZ
address
Used to jump to the provided address if CX = 0
LOOPE/ LOOPZ
address
Used to loop a group of instructions till it satisfies ZF = 1 & CX = 0
LOOPNE/ LOOPNZ
address
Used to loop a group of instructions till it satisfies ZF = 0 & CX = 0
raja
Published on 11-Mar-2019 11:32:18
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