Contec DIO-48DX-USB, User Manual

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3. External Connection
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DIO-48DX-USB
Connecting I/O Signals
The I/O circuits of interface blocks of this board are illustrated in Figure 3.3. Signals are TTL levels and
positive logic.
I/O Circuit
Figure 3.3. I/O Circuit
Example of Connection
When switch is "ON", the corresponding bit is "0". When switch is "OFF" in contrast, the corresponding bit is "1".
When "1" is output to a relevant bit, the corresponding LED comes on. When "0" is output to the bit, in contrast, the
LED goes out.
Figure 3.4. Connection Example Using 1-PA0 for Input and 2-PA0 for Output