Microprocessor

One byte instruction includes opcode and operand in the same byte.

The Load Accumulator Indirect (LDAX) and Store Accumulator Indirect (STAX) instructions provide a means of moving data between the accumulator and a memory location indirectly, with the RAM address contained in either the BC or DE register pair.

ADD with carry instruction will add the specified byte, either in a register or in the address contained by the H & L registers, and the value of the Carry bit, into the accumulator.

Decrement instruction provides a quick means of subtracting one from the content of a register or a memory location.

Subtract instruction subtracts the specified byte, in a register or in the address contained by the H & L register from the content of the accumulator.

Carry instruction allows direct control of the Carry flag by the programmer.

AND instruction performes a logical AND function between the specified byte, either in a register or in the address contained in the H & L register, and the contents of the accumulator.

This mode results in single-byte instruction. The byte contains bits which specifies a register pair, which in turn contains the address of the data in memory.

RETURN instruction provides a means, at the end of a subroutine, of resuming program execution at the instruction following the call instruction which invoked  the subroutine.

The effective address of the datum is in the base register BX or an index register that is specified by the instruction.

The instruction allows the MP to permit or deny interrupts under program control.

This replaces the contents of IP with part of the instruction and the segment of CS with another part of the instruction.

Zero Flag  is set to 1, if the result is zero and 0 if the result is non -zero.

The instruction used to clear interrupt flag in 8086 is CLI.

Auxiliary Carry Flag is set,  if there is a Carry out of bit 3 during an addition or a borrow by bit 3 during a subtraction.

OR is an operation where the output depends on any one of the two condition given, then output is true when any of the two inputs or both of them are true.

Binary Arithmetic Instruction may use any of the addressing modes for one of the operands, but, except when the source operand is immediate, one of the two operands must be a register.

OR is the operation where the output is true when any of the two inputs or both of them were true.

Intrasegment indirect, the effective branch having the content of register or memory location is accessed by using any of the data related addressing modes expect the immediate mode.

In EX-OR operation, the output is true only when one of the input was true and output is false if both inputs are at the same logic.

All Conditional Branch instructions have the 2 byte machine code format where the second byte gives a 8-bit signed displacement relative to the address of the next instruction in sequence.

Associative law of addition states that the net result remains same irrespective grouping of the variable.

Distributive law states that the Oring with one variable of the ANDed function, is similar to the ANDing of ORed result.

Accumulator is a 8-bit register that is a part of ALU. This register is used to store 8-bit data and to perform ALU operations. The result is stored in itself.