Embedded Programming Tips and Tricks
Revision as of 22:33, 12 November 2011 by 60.234.168.104 (talk) (Created page with "===Fast Division=== Very fast division can be done by bit shifting a variable right. Each shift does a divide by two. For example Y = Y >> 1 Will result in a divide by 2 X = X...")
Fast Division
Very fast division can be done by bit shifting a variable right. Each shift does a divide by two. For example
Y = Y >> 1 Will result in a divide by 2
X = X >> 4 Will result in a divide by 16
By adding a multiplication you can achieve other, more complex, divisions.
For example
Z = Z * 3; Z = Z >> 4; (div 16)
Will result in a division of 5.33 (16/3 = 5.33)
Be sure to do the multiply first, otherwise bits will be lost. Also be sure the variable size is large enough to store the multiplied value.