17
4 
3 
2 
1
8 
7 
6 
5
12 
11 
10 
9
16 
15 
14 
13
4 
3 
2 
1
8 
7 
6 
5
12 
11 
10 
9
16 
15 
14 
13
20 
19 
18 
17
24 
23 
22 
21
28 
27 
26 
25
32 
31 
30 
29
A
| I 0 |
|
| I 0 |
|
|
|
| MODEM |
D | C | B | A | TERMINAL |
D | C | B | A | TERMINAL |
D | C | B | A | TERMINAL |
D | C | B | A | TERMINAL |
|
|
|
| SWITCH |
|
|
|
| SWITCH |
D | C | B | A | DEVICE |
D | C | B | A | DEVICE |
D | C | B | A | DEVICE |
D | C | B | A | DEVICE |
D | C | B | A | DEVICE |
D | C | B | A | DEVICE |
D | C | B | A | DEVICE |
D | C | B | A | DEVICE |
B |
|
| A | CONTROL |
Fig. 3 General layout showing terminal port and device port numbers.
15