Instruction set of 8086.

          1.    Data transfer instructions :-

The various mneumonics used for data transfer instructions are MOV, XCHG, PUSH, POP, IN, OUT.

MOV – This instruction transfer data from one register or memory location to another register or memory locations.
PUSH – This pushes the contents of specified register or memory location on the stack.
POP – Reverse operation of PUSH ie POP from stack.
XCHG –It exchange the content of a register with the contents of any other register or

Read the rest of this entry »

Posted in 8086 - Micoprocessor

8086 - Interrupts

                        Interrupts is a signal send by an external device to the processor so as to request the processor to perform a particular task or work. The microprocessor allows normal program execution to be interrupted in order to carry out a specific task/work.

                       The interrupts are useful for efficient data transfer between processor and peripheral. When a peripheral is ready for data transfer, it interrupts the processor by sending an appropriate signal. Upon receiving an interrupt signal, the processor suspends the current program execution, save the status in stack and executes an

Read the rest of this entry »

Posted in 8086 - Micoprocessor

Special functions of 8086 registers.

AX:-
16 bit accumulator- Stores 16 bit result of certain arithmetic and logic operations.
BX:-
Base Register- Used to hold the base values in base addressing mode to access memory data.
CX:-
Count Register- Used to hold count value.
DX:-
Data Register- Used to hold data for multiplication and division.
SP:-
Stack Pointer- Used to hold offset address of top of stack memory.
BP:-
Base Pointer- Used to hold base value in base addressing.
SI:-
Source Index- Used to ho;d index value of source operand for string instructions.
DI:-
Destination Index- Used to hold index value of destination operand.

Read the rest of this entry »

Posted in 8086 - Micoprocessor