Tricky Intel 8085 Interview Preparation Guide
Download PDF

Intel 8085 Interview Questions and Answers will guide us that Intel 8085 is an 8-bit microprocessor introduced by Intel in 1977. It was binary-compatible with the more-famous Intel 8080 but required less supporting hardware, thus allowing simpler and less expensive microcomputer systems to be built. So learn more about Intel 8085 with the help of this Intel 8085 Interview Questions with Answers guide and get preparation for hardware based

39 8085 Questions and Answers:

Table of Contents:

Tricky  8085 Job Interview Questions and Answers
Tricky 8085 Job Interview Questions and Answers

1 :: What is Stack Pointer?

Stack pointer is a special purpose 16-bit register in the Microprocessor, which holds the address of the top of the stack.

2 :: What are the various flags used in 8085?

Sign flag, Zero flag, Auxillary flag, Parity flag, Carry flag.

3 :: In 8085 name the 16 bit registers?

Stack pointer and Program counter all have 16 bits.

4 :: What is the strength of the signal transmitted by powerful cell phones?

The powerful cell phones can transmit a signal of 3 watts.

5 :: What does Quality factor mean?

The Quality factor is also defined, as Q. So it is a number, which reflects the lossness of a circuit. Higher the Q, the lower are the losses.

the quality factor is measurement of efficiency(or effectiveness) of a device or circuitry.In literal sense quality factor means qualitative performance of a device.

6 :: Which interrupt is not level-sensitive in 8085?

RST 7.5 is a raising edge-triggering interrupt.


7 :: What is Program counter in 8085?

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.

8 :: Which is the Stack used in 8085?

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

9 :: What is meant by a bus?

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

A bus is two or many wire communication method.A bus which communicate between two active devices,it may transfer address,data,etc.

10 :: What is Tri-state logic?

Three Logic Levels are used and they are High, Low, High impedance state. The high and low are normal logic levels & high impedance state is electrical open circuit conditions. Tri-state logic has a third line called enable line.

11 :: Give an example of one address microprocessor?

8085 is a one address microprocessor.

In 8085 interupts are classified by software and hardware interupts.

12 :: In what way interrupts are classified in 8085?

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

13 :: What are Hardware interrupts?


14 :: What are Software interrupts?


15 :: Which interrupt has the highest priority?

TRAP has the highest priority

there are 2 types of interrupts external and internal.NMI has highest priority among all external interrupts,TRAP has highest priority among all internal interrupts.

16 :: Name 5 different addressing modes?

Register indirect,
Implied addressing modes.

17 :: How many interrupts are there in 8085?

There are 12 interrupts in 8085.

18 :: What is clock frequency for 8085?

3 MHz is the maximum clock frequency for 8085.

19 :: What is the RST for the TRAP?

RST 4.5 is called as TRAP.

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

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

21 :: Can an RC circuit be used as clock source for 8085?

Yes, it can be used, if an accurate clock frequency is not required. Also, the component cost is low compared to LC or Crystal.

22 :: Why address bus is unidirectional and data bus is bidirectional?

Because there is no need address transaction between processor and peripheral device but data bus is needed because data has to be read and write

23 :: Can 8259 be interfaced with 8085 via the trap pin?

i think if 8259 gives interrupt then it will be serviced immediately but since inta pin is left hanging the insr bit will never be set...and so whenever ny interrupt occurs depending upon priority itt will be serviced....also the isr address for all interrupts will be same ie 0024H...

Interrupt via trap is nonmaskable,so it will be serviced immediately.

25 :: What is the logical difference b/w Move A TO B and COMPUTE B = A?

In case of Move A TO B it will move whatever the value of a in to b.

it mean it will move numeric, alphanumeric and alphabatic value.

In case of COMPUTE B = A it will assign the vale of a in to b.

but in case of compute only numeric value will be compute.

mov a,b Ans- means whatever the data present on the 'b' it will transfer into 'a'
8085 Interview Questions and Answers
39 8085 Interview Questions and Answers