Practical Sheet 12 and 13 Interconnections

Question 1

How many opcodes we can have while in the hypothetical machine the opcode is using 4 bits. There is 16-bit word memory.

Answer 1

We can have 16 opcodes as we take the opcode number, and we do “4 to the power of 2 which is 16”.

Question 2

How many words of memory can be addressed (memory size)?

Answer 2

16-bit word memory. The opcode is 4, so the rest is 12. So the final number is 12 to the power of two which is 24

Question 3

1- Why do computers need interconnection systems?

Answer 3

So, the components can communicate with each other. Path for connecting the modules

Question 4

2- What does the interconnection structure depend on?

Answer 4

The design of this structure will depend on the type of the exchanges.

Question 5

3- What are the types of exchanges from/to the main memory?

Answer 5

Read and write, specifying the address and sending the signal.

Question 6

4- What are the types of exchanges from/to the I/O module?

Answer 6

Read and write data, send signals, external-internal data

Question 7

5- What are the types of exchanges from/to the CPU?

Answer 7

Addresses, Data, Signals

Question 8

6- What types of transfer does the interconnection structure support?

Answer 8

Memory to Processor – The processor reads an instruction or a unit of data from memory.
Processor To Memory – The processor writes a unit of data to memory
I/O to Processor – The processor read data from an I/O device via an I/O module
Processor to I/O – The processor send data to the I/O device.
I/O to or from Memory – The I/O module is allowed to exchange data directly with memory, without going through the processor, using direct memory access.

Question 9

7- What is a bus in computer systems? What are its key characteristics?

Answer 9

Communication pathway connecting two or more devices
That it is a shared transmission medium. ( Have an image of a Red London bus in your head, people can join at any time and they can leave whenever)

Question 10

8- What does shared transmission medium mean?

Answer 10

Have an image of a Red London bus in your head, people can join at any time and they can leave whenever.

Question 11

9- How do the signals overlap during transmission?

Answer 11

Only one device at a time can successfully transmit a signal, and when two are trying they overlap and become garble.

Question 12

10- What is a line in computer systems? What does it transmit?

Answer 12

The data lines provide a path for moving data among system modules, these lines collectively are called the data bus. It transmits bits, it can carry only 1 bit at a time.

Question 13

11- How many lines do a bus need to transmit 2 bytes of data?

Answer 13

It requires 16 lines as 2 bytes are 16 bits.

Question 14

12- What is a system bus?

Answer 14

A system bus is a single computer bus that connects the major components of a computer system.

Question 15

13- What are the different types of bus lines?

Answer 15

Control lines, address lines, data lines, and power distribution lines all of them combined is a system bus. Together combined lines of control lines are called control bus same goes for address and data

Question 16

14- What do the data lines do? What is a data bus?

Answer 16

They’re providing a path for moving data among system modules. The data bus is a name for a collective of lines.

Question 17

15- What do the address lines do? What is an address bus?

Answer 17

The address lines are used to designate the source or destination of the data on the data bus. The address bus is an element in a computer CPU that transmits the location of stored information

Question 18

16- What do the control lines do? What is a control bus?

Answer 18

The control lines are used to control the access to and the use of the data and address lines.

Question 19

17- How does the address bus determine the maximum possible memory capacity?

Answer 19

The maximum possible memory is defined by the bus width (e.g. 32 bit vs 64 bits)

Question 20

18- How are different I/O ports addressed in computers?

Answer 20

The higher-order bits (left side – selecting the module), Lower order bits (right side memory location or I/O port.

Question 21

19- How does a module (memory, I/O,… ) send data to another module in computers?

Answer 21

Obtaining the use of the bus as it is a shared medium means that we need to get enough lines for the data we want to send, then it is transferred.

Question 22

20- How does a module (memory, I/O,… ) request data from another module in computers?

Answer 22

Obtain the use of the bus, and transfer a request to another module over the appropriate control and address lines.

Question 23

21- What are the main advantages of using a point-to-point interconnection system?

Answer 23

Lower latency, higher data rate, better scalability

Question 24

23- What are the significant characteristics of QuickPath Interconnect (QPI)?

Answer 24

Multiple Direct Connections, Layered Protocol Architecture, Packetized Data Transfer