Specifications
Connection Example 2 (Digital Switches)
This example shows how the ID212 DC Input Unit can be wired using digital switches. Just as the keys on the
keyboard can turn ON different combinations of bits, the digital switches can control different combinations of bits.
For example, the combination of inputs on switch no. 1 and input point 00 turn ON bit 00 of word n. (For the sake of
simplicity, the figure below shows the digital switches wired to control 32 bits instead of 64 bits as was shown in
Example 1.) Wire STB 4, STB 5, STB 6, and STB 7 to access an additional 32 bits.
-
8
+
Switch no.
8
The following table shows the combinations enabled by wiring digital switches as shown.
Terminal Number
Word n
Word n + 1
Timing
Data 0 through
-
-
-
7
6
5
+
+
+
7
6
5
15
14
13
12
11
Switch no. 4
Switch no. 3
0
1
0
0
0
STB 1
Switch no. 8
Switch no. 7
1
0
0
0
0
STB 3
These pulses are input to bits 0 through 7 of word n.
4 ms
7
STB 0
STB 1
STB 2
STB 3
STB 4
STB 5
STB 6
STB 7
-
-
-
4
3
2
+
+
+
4
3
2
10
09
08
07
06
Switch no. 2
0
1
1
0
0
STB 0
Switch no. 6
1
1
1
0
1
STB 2
32 ms
Appendix B
0
DATA 0
1
DATA 1
2
DATA 2
3
DATA 3
4
DATA 4
5
DATA 5
6
DATA 6
7
DATA 7
COM (+24)
8
9
STB 0
10
STB 1
11
STB 2
12
STB 3
13
STB 4
14
STB 5
15
STB 6
16
STB 7
+
17
COM (0 V)
24 VDC
18
+24 VDC
D C B A COM
19
NC
-
1
+
1
05
04
03
02
01
Switch no. 1
1
1
0
0
0
Switch no. 5
1
0
0
1
0
00
1
1
117