Two's Complement Subtraction
written by Crystal Barchet and Teresa Carrigan
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WHAT IS IT?
This model demonstrates subtraction of numbers stored in two's complement format.
HOW IT WORKS
The two binary numbers are padded to eight bits. Next we take the two's complement of the number being subtracted, to get its negative. Finally, we add the two numbers. If the carry out of the last column is different from the carry into it, then overflow occurs (assuming the number of digits is fixed).
HomeApplets on this website were written by Teresa Carrigan in 2004, for use in computer science courses at Blackburn College, with the exception of the Fireworks applet. The applets made with NetLogo require Java 1.4.1 or higher to run. The applets made with NetBeans require Java 1.4.2 or higher to run. Applets might not run on Windows 95 or Mac OS 8 or 9. You may obtain the latest Java plugin from Sun's Java site.