(ou 
)
N3 |
N2 |
N1 |
N0 |
L |
R |
P |
|
0 |
0 |
0 |
1 |
1 |
1 |
0 |
|
0 |
0 |
1 |
0 |
1 |
1 |
0 |
|
0 |
0 |
1 |
1 |
0 |
0 |
0 |
|
0 |
1 |
0 |
0 |
0 |
0 |
0 |
|
0 |
1 |
0 |
1 |
0 |
0 |
0 |
|
0 |
1 |
1 |
0 |
0 |
1 |
1 |
|
0 |
1 |
1 |
1 |
0 |
1 |
1 |
|
1 |
0 |
0 |
0 |
0 |
1 |
1 |
|
1 |
0 |
0 |
1 |
1 |
0 |
1 |
|
1 |
0 |
1 |
0 |
1 |
0 |
1 |
On voit rapidement que : (ou )
![[schéma]](schema.gif)