©Sealevel Systems, Inc.
SL9049 - 06/2011
SeaI/O Manual
91
The SeaI/O-462 and SeaI/O-463 use 74ABT245 octal bi-directional transceivers to provide TTL
input/output capabilities and can sink 64mA and source 32mA. Each bit is pulled to +5V through a
10K ohm pull-up resistor to insure each bit is at a known state when not driven. The maximum
output power is +5V @ 1A (5W).
The SeaI/O-462‟s 96 digital I/O channels are brought out to two DB-78 Female connectors on
the front of the enclosure (pinout shown below). Each connector provides 48 bits of digital I/O
divided into six eight-bit ports. Each port may be individually configured via software command
as an input or an output.
Bits 1-48
Bits
A1
B1
C1
A2
B2
C2
D0
75
38
18
10
30
2
D1
76
37
17
9
29
1
D2
77
36
16
8
28
22
D3
78
35
15
7
27
21
D4
59
34
14
6
26
40
D5
39
33
13
5
25
60
D6
20
32
12
4
24
61
D7
19
31
11
3
23
62
Bits 49-96
Bits
A3
B3
C3
A4
B4
C4
D0
75
38
18
10
30
2
D1
76
37
17
9
29
1
D2
77
36
16
8
28
22
D3
78
35
15
7
27
21
D4
59
34
14
6
26
40
D5
39
33
13
5
25
60
D6
20
32
12
4
24
61
D7
19
31
11
3
23
62