Hi everybody ..
Could u help me in designin` a two 2-bit adder & a full subtractor ?
best regards,,

 

Have a look here:

http://www.play-hookey.com/digital/adder.html

http://www.play-hookey.com/digital/binary_subtraction.html

 

Work up a truth table and use that as a guide. Subtraction may be done by adding the compliments of the numbers.

 

ok , how will the truth tabe look like ?
PLZ Check if im going write or not

p q x y z
0 0 0 0 0 0 0
0 0 0 1 0 0 1
0 0 1 0 0 1 1
0 0 1 1 1 0 0
0 1 0 0 0 1 0
0 1 0 1 0 1 1
0 1 1 0 1 0 1
0 1 1 1 1 1 0
and so on

 

Have a look here:

http://www.play-hookey.com/digital/adder.html

http://www.play-hookey.com/digital/binary_subtraction.html

thanx alot