Task 4 (P6)
Describe the features of a processor
Multi-tasking
Multi-tasking is a method where multiple processes are dealt with at once sharing common processing recourses such as a CPU. It involves the CPU assigning which instructions to be carried out first but it only focuses on one instruction at a time.
Pipelining
Pipelining is a method in which the Processor begins to execute a second instruction before the first has finished. Every pipeline is divided into segments and each segment can be ran along side each other. When each segment completes its task it moves on to the next.
Cache (Level 1 and Level 2)
Cache is a portion of memory made of high-speed static RAM (SRAM). As a result Cache memory is much more efficient than the main memory (RAM) which is dynamic RAM (DRAM) that runs slower but also cheaper. The cache is a smaller, faster memory which stores copies of the data from the most frequently used main memory locations.
DRAM is dynamic in that, unlike SRAM, it needs to have its storage cells refreshed or given a new electronic charge every few milliseconds. SRAM does not need refreshing because it operates on the principle of moving current that is switched in one of two directions rather than a storage cell that holds a charge in place.
If the computer processor can find the data it needs for its next operation in cache memory, it will save time compared to having to get it from random access memory.
Level 1 cache is normally built on to the processor chip. It is extensively used for all sorts of purposes such as data fetching, data shifting and data loops, storing only small amounts of data.
Level 2 cache is normally located on the motherboard. L2 cache stores much more data, coming usually from the L1 cache. L2 cache can be up to sixteen times the size of L1 cache; this also means that it takes up much more room so it has to be located on the motherboard.
Clock Rate
The clock rate is the speed at which a processor clock oscillates constantly from a one to a zero, this is measured in hertz. The clock rates speed is determined by an oscillator crystal and amplifier circuit inside a clock generator circuit. The limiting factor of the clock rate is the time it takes for the signal line to settle down from its on state to off state. The Clock rate is also as fast as L2 cache.
Task 5 (P7)
Describe the operation of logic gates using truth tables
- NOT
- AND (2 inputs)
- OR (2 inputs)
Consider how these three main gates can be combined
NOT Logic Gate also known as (Inverter)
The output is “true” when only one input is “false.” Otherwise, the output is “false”. A Not gate is a logic gate which reverses the state of the input.
AND Logic Gate
The output is "true" when both inputs are "true." Otherwise, the output is "false."
OR Logic Gate
The output is "true" if either one or both of the inputs are "true." If both inputs are "false," then the output is "false."
These three main logic gates can be used to make other possible combinations of logic gates such as a NOR gate.
NOR Logic Gate
The NOR gate is a combination of an OR gate followed by an inverter. The output is "true" if both inputs are "false." Otherwise, the output is "false."
Task 6 (M1) Explain using examples how data travels around the processor
Task 7 (M2) Create logic circuits using simple logic gates and provide truth tables
This is a circuit that shows binary addition.
Here are a few examples of the circuit being carried out.
The Red circle/circles show input and Green circle/circles show output data
This can be shown in the truth tables below.
Task 8 (M4)
Provide a description of both astable and bistable flip- flops.
A flip-flop is an electrical circuit that can be in one of two states.
Astable flip flop
Astable flip flop is an oscillator which regularly switches states all the time. It has one 1 input and 1 Output. It can be used as a clock.
Bistable flip flop
Bistable flip flop is a memory device/gate which keeps one state indefinitely while it has power it also has 2 inputs and 2 outputs.
The difference between An Astable and Bistable flip flops.
A bistable flip-flop is a multivibrator with two stable states and can be put into either of its two states and it will stay like that.
An example of this could be:
A simple light switch; turn it on, it stays on, turn it off, it stays off.
Task 9 (D1)
Create complex logic circuits made up of arrays of simple logic circuits.
To produce an addition of two numbers each of four bit’s in length we must first.
You can add two numbers together each four bit in length by extending the first full adder’s carry out to another full adder and so on. Until you get 4 full adder’s each following on from the last carry out.
The way a full adder works:
The circuit adds two bits Input A and Input B, taking into account the previous carry in, to give the Sum, and the carry out.
Now we know how a full adder works we can now relate this to the idea of 4 full adders joined together by the last carry out and the diagram below illustrates this.
Diagram 1
These diagrams (below) will show you how you can add two four bit binary numbers together using a logic circuit.
Example 1
Binary
1111+
1111
______
11110
These binary numbers with value of 1 stand for both switches (The inputs i.e. the two four bit numbers added together) and the sum which in this case are shown by the flashing of LED lights (The sum is the output). 0 means no switch or light is active.
The first line of inputs for this study will always be A4,A3,A2,A1
The second line of inputs for this study will always be B4,B3,B2,B1 these two numbers will be added together
Then it is a long underscore followed by Carrys C3,C2,C1 directly underneath
And then finally the output sum shown as O (Overflow) S4,S3,S2,S1
The following equation should look like this
(1) (1) (1) (1)
A1 A2 A3 A4 +
(1) (1) (1) (1)
B1 B2 B3 B4
______________
(1)(1)(1)
C3 C2 C1
(1)(1)(1)(1)(0)
O S4 S3 S2 S1
Diagram 2 (The labels from Diagram 1 still apply for this Diagram and the others)
Example 2
Binary
1001+
1101
______
10110
The following equation should look like this
(1) (0) (0) (1)
A1 A2 A3 A4 +
(1) (1) (0) (1)
B1 B2 B3 B4
______________
(0)(0)(1)
C3 C2 C1
(1)(0)(1)(1)(0)
O S4 S3 S2 S1
Example 3
Binary
1001+
1001
______
1111
The following equation should look like this
(0) (1) (1) (0)
A1 A2 A3 A4 +
(1) (0) (0) (1)
B1 B2 B3 B4
______________
(0)(0)(0)
C3 C2 C1
(0)(1)(1)(1)(1)
O S4 S3 S2 S1
Example 4
Binary
0111+
1101
______
10100
The following equation should look like this
(0) (1) (1) (1)
A1 A2 A3 A4 +
(1) (1) (0) (1)
B1 B2 B3 B4
______________
(1)(1)(1)
C3 C2 C1
(1)(0)(1)(0)(0)
O S4 S3 S2 S1
Task 10 (D2)
Compare and contrast two different processors
I will compare the AMD Opteron quad core and the Intel core 2 quad processor q9650.
Key components:
Front Side Bus – The Front Side Bus allows the components to send and receive data from the CPU to the North Bridge and vise versa. The faster a computer's bus speed, the faster it will operate, but a fast bus speed can’t make up for a slow Clock Speed.
Clock Speed – The Clock Speed is the speed at which a microprocessor executes instructions these clock cycles per second are measured in hertz.
Special Features:
Virtualization –Virtualization also known as a virtual machine makes it possible to run multiple operating systems on one computer.
SpeedStep Technology – SpeedStep Technology is built into some new Intel processors this can be used to change the clock speed by using a piece of software.
Speed Step Technology allows the processor to keep up with performed operations. It greatly reduces power consumption and heat loss.
Smart Fetch Technology – Smart Fetch Technology allows the processor core to enter a "halt" state and draw less power, which reduces CPU power consumption.
Recommendation:
Both processors have Quad-Core technology and 64 bit computing, however the difference is in the Clock speed, Cache memory and the extra features. Both processors have similar special features such as the AMD Rapid Virtualization Indexing and the Intel Virtualization Technology. Although the Intel core 2 quad processor q9650 has no L3 cache I think that the higher clock speed and L2 cache more than makes up for not having any L3 cache. Not to mention the Intel core 2 quad processor q9650 has Speed Step Technology which makes for a much greater performance.
The Intel core 2 quad processor q9650 is more expensive but it is a price worth paying for such a greater performance.
