sample question of microprocessor
- Explain Microprocessor.
A microprocessor is a multipurpose, programmable clock driven, registers based electronic device that reads binary instruction from memory or storage device, accepts binary data as input and gives data according to inputs i.e. instructions.
2. What are the various elements of MPU (microprocessor unit)
There are four elements of MPU.
- Input section
- Output section
- Primary memory
- Secondary memory
3. What happens when 8086 mp receives DMA request on RQ/GT0 & RQ/GT1 pins simultaneously?
when the mp receives the request simultaneously then request on pin RQ/GT0 will be given priority.
4. What are the five groups of interrupt supported by 8086 mp?
- External hardware interrupt
- Software interrupt
- Internal interrupt
- Non maskable interrupt & Reset
5. what are the hardware interrupt pin of 8086
NMI ( non maskable interrupt )
INTR (interrupt request)
6. What name is given to special software routine to which control is passed when an interrupt occurs?
ISR ( interrupt service routine )
7. Draw the architecture diagram of 8086.
8. Briefly explain the concept of DMA.
Ans: DMA stands for Direct memory access. This Is one of the features of modern computer. This allows certain hardware subsystems within the computer to access system memory independently from CPU.
9. Explain address bus and data bus ?
Address bus is unidirectional in nature. It is due to the address locations are sent by mp to memory or input output devices.
The data bus is bidirectional in nature. It is due to mp accepts datas from outside devices as well as sent the datas to outside device.
10.What is idle state?
An idle state is a period of no bus activity that occurs because the pre fetch queue is full and the instruction current being executed does not require bus activity.
Long Questions(any five):
A.Draw and explain the pin diagram of 8086 mp.
B. What are the functions of segment register? What are the functions of general purpose register?
Function of segment register :
The segment register in the mp provides a base address for any memory access.
There are four segment registers, given as follow:
CS – Code Segment
DS – Data Segment
SS – Stack Segment
ES – Extra Segment.
Function of GPR :
General purpose registers have several uses these are used as following:
- Low registers
- High registers
- Stack pointer
- Link register
- Program counter
C.Draw the diagram of IE register and explain all the pins .
D. Define interrupts. And explain interrupt in 8051.
*Interrupt is facility provided by microprocessor to the outside programs by which the attention of mp can be diverted to do some higher priority jobs.
* The mp scans the interrupt signal on the interrupt pin during every machine cycle.
* When the interrupt signal is high the mp suspends its current task and switch to the new task given by the user.
* It executes its task in stack.
* After completion of task i.e. data transfer the mp retrieves to the task it was doing and starts its job from stack and restart the previous one.
E. Draw the Pin diagram of 8279 and explain the functions of each block.