Each character has been assigned a 7 bit binary string in the ASCII table, e.g. 'A' 100 0001
ASCII stands for American Standard Code for Information Interchange
ASCII is standardised which means that all comptuters can understand downloaded documents, for example, as they all decode the binary into characters using the same table
However, the problem with ASCII is that it can only fit 128characters
Whereas, extended ASCII can fit 256 characters, as it is 8bit
Unicode was added so that characters from languages all around the world can be universally understood, it is an extension of ASCII that stores characters as 16bit binary, which allows for 65,536 different characters
Therefore, the greater the number of bits per character in a character set the greater the number of characters that can be represented
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Bitmaps
Images are stored as a series of 1's and 0's
A pixel is the smallest picture element
The resolution is how many pixels there are usually per inch of the screen
The higher the resolution the higher the fidelity, this is because there are smaller 'squares' in the overlay of the original picture, so when it is digitalized and the combination of all of the colours in each square is produced there will be a more accurate representation of the colour; however there will also be an increased file size
Colour/bit Depth - is the number of bits that are avaliable to represent colour, for example the normal bit depth used in digital images, is 24bits which means there are 8 bits avaliable for Red, Green and Blue; there are 256 colour variations for each so the fidelity is increased
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Instructions
Instructions are made up of three parts: the Op-code. the number bit and the operand
Op-code - is the process that is going to be carried out, e.g. add
Number bit - is used to indicate whether the data in the operand is a value or address
Operand - contains the data that is going to be processed
An 8 bit instruction looks something like this: 010 1 0001
The instructions are processed by the CPU, an instruction is fetched to the CPU and the instructions is sent to different sections of the CPU where it is decoded and then the instruction is executed
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