National Instruments NI USB-9421 用户手册
© National Instruments Corporation
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NI USB-9421 User Guide and Specifications
Each channel of the NI USB-9421 has a terminal or pin, DI, to which you
can connect voltage or current signals. The NI USB-9421 also has a
common terminal or pin, COM, that is internally connected to the isolated
reference of the module. Each digital input channel on the NI USB-9421
has an LED that indicates the state of that channel. Refer to Table 3 for the
terminal assignments of the NI USB-9421 with screw terminal. Refer to
Figure 7 for the pin assignments of the NI USB-9421 with D-SUB.
can connect voltage or current signals. The NI USB-9421 also has a
common terminal or pin, COM, that is internally connected to the isolated
reference of the module. Each digital input channel on the NI USB-9421
has an LED that indicates the state of that channel. Refer to Table 3 for the
terminal assignments of the NI USB-9421 with screw terminal. Refer to
Figure 7 for the pin assignments of the NI USB-9421 with D-SUB.
Table 3. Terminal Assignments
Module
Terminal
Signal
0
DI0
1
DI1
2
DI2
3
DI3
4
DI4
5
DI5
6
DI6
7
DI7
8
No connection
9
Common (COM)
0
1
2
3
4
5
6
7
8
9
0
3
4
7