1&2 Number Systems And Binary Flashcards
How do you calculate the greatest number that can be created with x bits
(2^x)-1
Which bit is the least significant bit
The right most bit
Which bit is referred to as the most significant bit?
The left most bit
How are decimals stored in binary?
They are stored as powers of 2^-x e.g. the mixed number system looks like:
4 2 1 0.5 0.25 0.125
How are negative numbers stored?
Twos complement
How is two’s complement calculated out on a denary number?
- Convert the number to its binary equivalent
- Starting from the LSB copy all bit up to and including the first 1
- Invert all other bits after this (1s become 0s vice versa)
- Convert the MSBs denary value to a negative
What are the rules for addition in binary?
Layout the two numbers in a table with one above the other
0+0=0
1+0=1
1+1=0 carry 1 to next bits
1+1+1 carry=1 carry 1 to next bits
How do you subtract in binary?
Convert the number you are subtracting into a negative twos complement number and add it to the other number. Check that the resulting binary is the correct number.
How do you multiply in binary?
Place both number in a table (one above the other)
At each nought int he bottom number write all noughts in the corresponding row.
When you come to a one, copy the entire binary number above, writing its LSB starting at the position of the one.
Describe repeated division by 2