Serial Adder Subtractor
Posted: Wed Jan 29, 2014 4:10 am
How will you construct and test a serial adder-subtractor circuit using JK flip-flop and shift registers? Thank you in advance 
Try to look at these images:
https://www.google.com/search?q=serial+ ... 0&bih=1053
As one example you can download a sample circuit Digital Clock: http://logiccircuit.codeplex.com/releases/
There are some adders there.