Full Subtractor A B where A 0111 B 1011 Ci 0 Draw the Su

Full Subtractor. A - B where: A = 0111, B = 1011, Ci = 0 Draw the Subtractor truth table for A, B, Ci, D, Co (show all eight possibilities for A, B, Ci and count in ordinary binary). For bits 0-3 determine the values for A, B, Ci, D, Co. Show your answer by listing the values for Co3, D3, D2, D1, D0. Show how from part (c) you would get the correct answer.

Solution

a) Full subractor truth table

I could not understand question C and D

A	B	Ci	D(Difference)	Co(Barrow)
0	0	0	0	0
0	0	1	1	1
0	1	0	1	1
0	1	1	0	1
1	0	0	1	0
1	0	1	0	0
1	1	0	0	0
1	1	1	1	1