Name of the College : Noorul Islam College of Engineering
University : Anna University
Degree : M.Sc
Department : Software Engineering
Subject Code/Name : XCS 234 – Microprocessor
Document Type : Question Bank
Website : niceindia.com
Download Model/Sample Question Paper : https://www.pdfquestion.in/uploads/niceindia.com/3132-XCs_234_Microprocessors.pdf
NICE Microprocessor Question Paper
Unit – I
1. Define microprocessor? :
A microprocessor is a multipurpose, programmable, clock-driven, register-based electronic device that reads binary instructions from a storage device called memory accepts binary data as input and processes data according to instructions, and provides result as output.
Related : Noorul Islam College of Engineering XCS471 Principles of Management M.Sc Question Bank : www.pdfquestion.in/3138.html
2. Define microcomputer? :
A computer that is designed using a microprocessor as its CPU. It includes microprocessor, memory, and I/O.
3. Define ROM? :
A memory that stores binary information permanently. The information can be read from this memory but cannot be altered.
4. What is an ALU? :
The group of circuits that provides timing and signals to all operation in the computer and controls data flow.
5. Define small-scale integration? :
The process of designing a few circuits on a single chip. The term refers to the technology used to fabricate logic gates on a chip.
Unit – II
6. What is an instruction? :
An instruction is a binary pattern entered through an input device in memory to command the microprocessor to perform specific function.
7. What are the four primary operations of a MPU? :
1. Memory read
2. Memory write
3. I/O read
4. I/O write
8. What do you mean by address bus? :
The address bus is a group of 16 lines generally identified as A0 to A15. The address bus is unidirectional : bits flow from MPU to peripheral devices.
9. How many memory locations can be addressed by a microprocessor with 14 address lines? :
The 8085 MPU with its 14-bit address is capable of addressing 214 =16,384 (ie) 16K memory locations.
10. Why is the data bus bi-directional? :
The data bus is bi-directional because the data flow in both directions between the MPU and memory and peripheral devices.
11. What is the function of the accumulator? :
The accumulator is the register used to store the 8-bit data to perform the arithmetic and logical operations.
12. Define control bus? :
This is single line that is generated by the MPU to provide timing of various operations.
14. What is a flag? :
The data conditions, after arithmetic or logical operations, are indicated by setting or resetting the flip-flops called flags.
15. Why are the program counter and the stack pointer 16-bit registers? :
Memory locations for the program counter and stack pointer have 16-bit addresses. So the PC and SP have 16-bit registers.
16. Define memory word? :
The number of bits stored in a register is called a memory word.
17. Specify the number of registers and memory cells required in a 128 x 4 memory chip? :
Number of registers = 128
Memory cells required is 128 x 4=512
18. Explain the function of ALE and IO/M signals in the 8085 architecture? :
The ALE signal goes high at the beginning of each machine cycle indicating the availability of the address on the address bus, and the signal is used to latch the loworder address bus. The IO/M signal is a status signal indicating whether the machine cycle is I/O or memory operation.The IO/M signal is combined with the RD and WR control signals to generate IOR, IOW, MEMW,MEMR .
19. If the 8085 adds 87H and 79H, specify the contents of the accumulator and the status of the S, Z, and CY flag? :
The sum of 87H and 79H =100H. Therefore, the accumulator will have 00H, and the flags will be S =0, Z = 1, CY = 1
20. Write down the control and status signals? :
Two Control signals and three status signals
Control signals : RD and WR
Status signals : IO/M, S1, S2
Unit – III
21. Define machine cycle? :
Machine cycle is defined, as the time required completing one operation of accessing memory, I/O, or acknowledging an external request.
22. Define T-state? :
T-state is defined as one subdivision of the operation of performed in one clock period.
23. What is a transparent latch? : Why is it necessary to latch with output devices such as LED’s?:
A transparent latch is a flip-flop; its output changes according to input when the clock signal is high, and it latches the input on the trailing edge of the clock. The latch is necessary for output devices to retain the result; otherwise the result will disappear
25. Define instruction cycle? :
Instruction cycle is defined, as the time required completing the execution of the instruction.