Define Segment Override Prefix.
Segment Override Prefix : To permit exceptions to the Segment Register usage, a special one byte instruction called a segment override prefix is available . It is... Read more »
‘Microprocessors Interview Questions’ - KyaPoocha.com
What is Unpacked BCD Format ?
Unpacked BCD Format : In Unpacked BCD, there is only one digit per byte and because of this,unpacked multiplication and division can be done. Binary operations act... Read more »
What is AAS instruction in 8086 ?
Adjust Result of ASCII Subtraction This instruction adjust the binary result of SUB or SBB instruction. Read more »
What is the use of Directives in 8086 ?
Directives in 8086 give directions to the assembler during the assembly process but are not translated into machine instruction. Read more »
What is Programmed I/O ?
Programmed I/O : It consists of continually examining the status of an Interface and performing an I/O operation with the Interface when its status indicates that... Read more »
Write about the following instruction :
MOV CS:[BX], DL MOV CS:[BX],DL - It copies a byte from DL Register. Effective Address for the memory location is contained in the BX Register. Normally an... Read more »
What is difference between DIV and IDIV instruction in 8086 ?
DIV : It operates only on unsigned number. IDIV : It operates only on signed numbers. Read more »
What is Packed BCD Format ?
Packed BCD Format : Packed BCD Numbers are stored in two digits to a byte , in 4 bit groups referred to as nibbles. ALU is capable of performing only binary addition... Read more »
What is DAS instruction ?
DAS : Decimal Adjust After Subtraction This instruction converts the binary result of a SUB or SBB instruction in AL to Packed BCD format. It operates only on AL... Read more »
What is the use of ‘W’ bit in opcode ?.
W bit in op-code : If an instruction in 8086 can operate on either a byte or a word , the op-code includes a W-bit which indicates whether a byte ( W =0 ) or a... Read more »
Define XLAT instruction used in 8086.
It translates a byte in AL using a table in memory. The offset address is calculated by adding the 8 bit contents of the AL register and the contents of BX register.... Read more »
What is the use of PUSHF instruction used in 8086 ?
It pushes the flag register contents to the top of the stack. No flags are affected. Read more »
Define Inter segment Indirect addressing mode:
It replaces the contents of IP and CS with the contents of two consecutive words in memory that are referenced by using any of the data related addressing modes... Read more »
Define Inter segment addressing mode:
It replaces the contents of IP with part of the instruction and the contents of CS with another part of the instruction. Read more »
Define Intra segment Indirect addressing mode:
The effective branch address is the contents of a register or memory location that is accessed using any of the data related addressing modes except the immediate... Read more »