Binary Subtraction
Negative numbers are represented in 2 complement form and subtraction is also per formed using 2 complement method in microprocessor. Hence we will discuss only 2 compliment method of subtraction in this book.
To find 2 compliment of any binary number
Use followings steps
Find 1 complement of the given binary number convert all 0 to 1 and all 1 to 0 s.
Add 1 to the obtained d1 complement number to get the 2 complement of the original number.
The obtained binary number will be the negative of the given number.
Example : Find 2 complement of 010110112. ( equal to + 91^{10})
Solution : 1 complement of the given number is: 10100100
Add 1 1
The 2 complement form of the number 101000101
This will represent -91_{10} in microprocessor.