Difference between CALL and JUMP instructions

MicroprocessorMicrocontroller8085

In this section, we will see what are the differences between CALL and JUMP instruction. The CALL instruction is used to call a subroutine, but the JUMP instruction updates the program counter value and point to another location inside the program.

Now let us see some detailed differences between CALL and JUMP instructions.

JUMP Instruction
CALL instruction
By using JUMP, the program control transfers to a location which is also a part of the main program
By using CALL instruction, the program control transfers to a location which is not a part of main program.
Here the addressing mode is Immediate
Here the addressing mode is Immediate and Register Indirect.
We do not need to initialize the Stack Pointer (SP) to perform the JUMP instruction.
We have to initialize the Stack Pointer (SP) before using some CALL instruction.
The program counter value is not Pushed into Stack
The value of program counter is pushed into stack before going to the pointed location.
No return instruction is needed after JUMP instruction.
After CALL, it enters into a subroutine, to come back from subroutine we need return instruction.
The value of stack pointer remain unchanged
The value of Stack Pointer is decremented by 2.
10 T-States are required to perform JUMP instruction
18 T-States are required to perform CALL instruction.
3 Machine cycles are needed for JUMP
5 Machine cycles are needed for CALL.
raja
Published on 11-Mar-2019 11:40:17
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