Two Marks Questions with Answers

Two Marks Questions with Answers

 

Q.1 What is memory mapping ?

Ans. : The assignment of memory addresses to various registers in a memory chip is called memory mapping.

 

Q.2 What is I/O mapping ?

Ans. : The assignment of addresses to various I/O devices in the memory chip is called I/O mapping.

 

Q.3    Show the common anode seven segment LED configuration. How to switch it on and off ?

(Refer section 7.2)

 

Q.4 State the disadvantages of memory mapped I/O scheme.

(Refer section 7.2.4)

 

Q.5    Write the difference between memory mapped I/O and peripheral mapped I/O.

(Refer section 7.2.4.1)

 

Q.6    What is the significance of I/O ports ?

Ans. : I/O ports allow to transfer data from input devices such as keyboard to the microprocessor and from microprocessor to the output devices such as display devices.

 

Q.7 What are the different data transfer schemes ?

Ans. : Different data transfer schemes are :

• Programmed I/O or Polling control

• Interrupt driven I/O

• DMA transfer (Hardware Controlled I/O)

• I/O controlled by handshake signals

• I/O controlled by ready signal

 

Q.8 What are the requirements to be met while interfacing I/O microprocessor/microcontroller ?

Ans. : The requirements to be met while interfacing I/O devices to microprocessor/microcontroller are :

• I/O port and circuit to select I/O port

• Mechanism to synchronize data transfer

• Level translator if voltage levels are different

• Buffers if sourcing current requirements are beyond the microprocessor/microcontrollers.

 

Q.9 Write the difference between standard I/O and memory mapped I/O.

(Refer section 7.2.4.1)

 

Q.10 Why an interface is needed in between CPU and input-output device

Ans. : An interface is necessary to coordinate the transfer of data between and external devices. The functions performed by an I/O interface are :

1. Handle data transfer between much slower peripherals and CPU or me

2. Handle data transfer between CPU or memory and peripherals having data formats and word lengths.

3. Match signal levels of different I/O protocols with computer signal levt

4. Provides necessary driving capabilities - sinking and sourcing currents.

 

 

 

University Questions with Answers (Long Answered Questions)

(Regulation 2008)

May-12

Q.1 Describe the comparision of I/O mapped and memory mapped I/O interfacing.

 (Refer section 7.2) [8]

Dec.-12

Q.2 Deaw the decode logic for LED output port in an I/O interface.

(Refer section 7.2) [8]

 

(Regulation 2013)

May-16

Q.3 Compare memory mapping and I/O mapping technique in 8085.

(Refer section 7.2.4.1) [8]