Computer System Architecture NDCSA1

P1

A computer is not able to work with our alphabet such as A B or C, it will be translated into code. Every key I type on the keyboard gets turned into a coded number witch gets turned into binary code. For example the letter A is 65 which would be translated into 1000001 or 0110 0101, this second code is Binary Coded Decimal (BCD). That is when the machine breaks each part down into a single unit and works it out with binary code.

To work out this code to 8bit binary you have to go according to the table and get each number and letter and convert it into to decimal first and then binary

                                                                                                                          ABC0111:

A=10=00001010
B=11=00001011

C=12=00001100

0=0=000000000

1=1=00000001

1=1=00000001

1=1=00000001

Height (metres)	Temperature (Celsius)	Atmospheric Pressure (kPa)
100	15	100.15
6000	-38	48.21

Converted in 16bit binary  

Height (metres)
	32768	16384	8192	4096	2048	1024	512	256	128	64	32	16	8	4	2	1
100	0	0	0	0	0	0	0	0	0	1	1	0	0	1	0	0
6000	0	0	0	1	0	1	1	1	0	1	1	1	0	0	0	0

Temperature (Celsius)
	32768	16384	8192	4096	2048	1024	512	256	128	64	32	16	8	4	2	1
15	0	0	0	0	0	0	0	0	0	0	0	0	1	1	1	1
-38	0	0	0	0	0	0	0	0	0	0	1	0	0	1	1	0
Flip Bits	1	1	1	1	1	1	1	1	1	1	0	1	1	0	0	1
+1 to the significant bit	1	1	1	1	1	1	1	1	1	1	0	1	1	0	1	0
Therefore	-32768	+16384	+8192	+4096	+2048	+1024	+512	+256	+128	+64	0	+16	+8	0	+2	0

Atmospheric Pressure (kPa)
	Sign	Mantissa														Exponent
100.15	0	0	0	0	1	1	0	0	1	0	0	1	1	1	1	1
48.21	0	1	1	0	0	1	0	0	0	1	1	0	1	1	1	0

+5

P2

This controller works by the machine accepting the hand movement with the help of the sensors and converts it into a mathematical code which then moves the virtual body in the computer in the same way.

-5

 

The Joystick is connected to potentiometers. Each potentiometer is used to record for left and right and forward and backwards movements. When the controller makes a movement the potentiometer sends the details of the Y and X coordinates to the CPU and the required movement is achieved.

RGB Code                                                                                          Binary

                                                            0000 0000 1111 1111 0000 0000

A digital camera has a light-sensing grid called CMOS which can record light as binary data that presents the brightness and the colour frequencies. It records the data for millions of individual points called pixels which can be put together to recreate the original image. This is the same technology used in almost all computer images.

To send a picture to a friend by email to do this you need the image to be converted in the language that the computer recognizes bits and bytes.    

Any recording starts with an analogue audio signal. Analogue signal is an electrical impression of a sound's vibration waveform that reach your ears. Sound is caused by vibrations in air.

A microphone works a bit like your eardrum: That electricity is the sound, but instead of waves in air it's sent as waves in electrical voltage. Sound recording equipment then transfers the microphone's electrical signal to some kind of storage, like tape, or it might be converted into digital data that you can store to a computer. It has to convert it into binary so the computer can communicate.

M1

A computer can only communicate with values of 1's and 0's. The 1's and 0's pair to form a byte with 8 bits, a word which is 16 bits or a double word which has 32 bits. Eg: A value to 10 in a computer is really 1010. Since integer values are only whole number you must use a floating point representation of a real or fractional number. A floating point number can have different formats. The one that Allen-Bradley uses is IEEE-754. Which uses 32 bits and is considered single precision floating point. This format has a sign bit, 8 exponent bits and 23 fractional bits or mantissa.

Floating point representation of a real number 10 would be:

10 = 0 10000010 0100000 0000000000000000

S = Sign Bit              E = Exponent                       M = Mantissa

S= it indicates the of the number. Example if the sign bit is 1 then the number is negative

Mantissa= the decimal part of common logarithm

Exponent= The exponent of a number shows you how many times the number is to be used in a multiplication.

It is written as a small number to the right and above the base number.

In this example: 82 = 8 × 8 = 64