# Unit 6 - Data Types Flashcards

binary addition rules

- 0 + 0 = 0
- 0 + 1 = 1
- 1 + 1 = 0 carry 1
- 1 + 1 + 1 = 1 carry 1

what is an overflow

when the arithmetic result exceeds the available number of bits

what does one shift to the left do

x 2

what does one shift to the right do

/2

how does twos complement work

-128, 64, 32, 16, 8, 4, 2, 1

how to work out if the denary value will be positive or negative in twos complement

starts with 0 = positive

starts with 1 = negative

how convert a negative denary number to binary

- flip all of the bits
- add 1

how to convert a negative twos complement binary number to denary

- flip the bits
- add one
- negative sign in-front of byte
- convert

how to do binary subtraction using twos complement

- convert negative binary number into twos complement
- add positive binary value and twos complement value

why are fixed point binary number useful

- represent fractions in binary
- increased performance

what is limited by fixed point binary

- range

advantages of floating point binary

- greater range
- greater accuracy

what does moving the point to the right in floating point binary do

increase range

reduces precision

what does moving the point to the left in floating point binary do

reduces range

increases precision

what is the mantissa

the coefficient

what is the exponent

the order of magnitude