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C5808 Pages:

List any four features of 8257 DMA Controller.

PART E
Answer any four full questions, each carries 10 marks

What is a microcontroller? Distinguish between a microcontroller and a
microprocessor.

What are the five different addressing modes available in 8051 microcontroller?
With the help of a block diagram describe the different components of 8051.
Consider four LEDs connected to the lower 4 bits of Port PO of 8051
microcontroller. Assume that the LEDs shall glow if the corresponding bit is 1.
Write an 8051 program which makes the group of LEDs to function as 4-bit Ring
Counter. The program should iterate to display the Ring Counter sequence five
times continuously and then exit. (Hint: 4bit Ring Counter sequence is 1000,
0100, 0010, 0001)

Describe the architecture and functionalities of 8253 interval timer.

What are the five different categories of 8051 instruction set? Explain each
category with appropriate examples.

What are the five different interrupts in 8051?

Write an 8051 program to find the sum of digits of an 8bit unsigned decimal

number.
1.

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