Set - 4

Question 1 :

What is meant by a bus?

Answer :

A bus is a group of conducting lines that carriers data, address, & control signals.


Question 2 :

What are the various registers in 8085?

Answer :

Accumulator register, Temporary register, Instruction register, Stack Pointer, Program Counter are the various registers in 8085


Question 3 :

Why crystal is a preferred clock source?

Answer :

Because of high stability, large Q (Quality Factor) & the frequency that doesn't drift with aging. Crystal is used as a clock source most of the times.


Question 4 :

In 8085 which is called as High order / Low order Register?

Answer :

Flag is called as Low order register & Accumulator is called as High order Register.


Question 5 :

Name 5 different addressing modes?

Answer :

Immediate, Direct, Register, Register indirect, Implied addressing modes


Question 6 :

In what way interrupts are classified in 8085?

Answer :

In 8085 the interrupts are classified as Hardware and Software interrupts.


Question 7 :

What is the difference between primary & secondary storage device?

Answer :

In primary storage device the storage capacity is limited. It has a volatile memory. In secondary storage device the storage capacity is larger. It is a nonvolatile memory. Primary devices are: RAM / ROM. Secondary devices are: Floppy disc / Hard disk.


Question 8 :

Which Stack is used in 8085?

Answer :

LIFO (Last In First Out) stack is used in 8085.In this type of Stack the last stored information can be retrieved first.


Question 9 :

What is Program counter?

Answer :

Program counter holds the address of either the first byte of the next instruction to be fetched for execution or the address of the next byte of a multi byte instruction, which has not been completely fetched. In both the cases it gets incremented automatically one by one as the instruction bytes get fetched. Also Program register keeps the address of the next instruction.


Question 10 :

What is the RST for the TRAP?

Answer :

RST 4.5 is called as TRAP.