NI NI-9853, Руководство пользователя

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Pinouts for CAN0 and CAN1 of the NI-9853 are listed in Tables 1 and 2.
Table 4 lists recommended termination resistor values.
Connector Pin Signal
6
7
8
9
1
2
3
4
5
1 No Connection (NC)
2 CAN_L
3 COM
4 NC
5 SHLD
6 COM
7 CAN_H
8 NC
9 NC
Table 1. Pin Assignments for CAN0
Connector Pin Signal
6
7
8
9
1
2
3
4
5
1 No Connection (NC)
2 CAN_L
3 COM
4 NC
5 SHLD
6 COM
7 CAN_H
8 NC
9 V
SUP
Table 2. Pin Assignments for CAN1
CAN Bus Topology and Termination
A CAN bus consists of two or more CAN nodes cabled together. The CAN_H and
CAN_L pins of each node are connected to the main CAN bus cable through a short
connection known as a “stub.” The pair of signal wires, CAN_H and CAN_L,
constitutes a transmission line. If the transmission line is not terminated, each
signal change on the bus causes reflections that may cause communication errors.
Because the CAN bus is bidirectional, both ends of the cable must be terminated.
© National Instruments
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NI-9853