What is the number of bit patterns provided by a 7-bit code?
What is the number of bit patterns provided by a 7-bit code?
The correct option is A 128
128 is the number of bit patterns provided by a 7-bit
code
probably know that around then (1960's), an 8-bit byte
was becoming the standard way that computer hardware was built, and that you
can store 128 different numbers in a 7-bit number. When you counted all
possible alphanumeric characters you
ended up a value of 90-something. It was therefore decided to use 7 bits to
store the new ASCII code, with the eighth bit being used as a parity bit to
detect transmission errors.
Over time, this table had limitations which were overcome
in different ways. First, there were "extended" or "8-bit"
variations to accomodate European languages primarily, or mathematical symbols.
These are not "standards", but used by different computers,
languages, manufacturers, printers at different times. Thus there are many
variations of the 8-bit or extended "ascii table". None of them is
reproduced here, but you can read about them in the references below.
128 is the number of bit patterns provided by a 7-bit code
probably know that around then (1960's), an 8-bit byte was becoming the standard way that computer hardware was built, and that you can store 128 different numbers in a 7-bit number. When you counted all possible alphanumeric characters you ended up a value of 90-something. It was therefore decided to use 7 bits to store the new ASCII code, with the eighth bit being used as a parity bit to detect transmission errors.
Over time, this table had limitations which were overcome in different ways. First, there were "extended" or "8-bit" variations to accomodate European languages primarily, or mathematical symbols. These are not "standards", but used by different computers, languages, manufacturers, printers at different times. Thus there are many variations of the 8-bit or extended "ascii table". None of them is reproduced here, but you can read about them in the references below.
