|GAL22V10B in: (A3, A2, A1, A0, B3, B2, B1, B0, P),
| 	   io: (S3, S2, S1, S0, C3, C2, C1, C0)
|
| S0 = (A0 ## (B0##P)) 
| C0 = (A0&(B0##P))
| S1 =  C0 ## A1 ## (B1 ## P)
| C1 = ((A1##(B1##P)) & C0)# (A1&(B1##P))
| S2 =  C1 ## A2 ## (B2##P)
| C2 = ((A2##(B2##P)) & C1)# (A2&(B2##P))
| S3 =  C2 ## A3 ## (B3##P)
| C3 = ((A3##(B3##P)) & C2)# (A3&(B3##P))