OPTO 22 G4LC32ISA-LT, Руководство пользователя

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G4LC32ISA-LT User’s Guide 3-11
Table 3-4: Pin Descriptions for the RS-232 Serial Ports
Pin COM0 and COM1
1 +5 VDC 1
2 Transmit (TX)
3 Receive (RX)
4 Request-to-Send (RTS)
5 Clear-to-Send (CTS)
6 Data Terminal Ready (DTR)
7 Ground (GND)
1 The +5 VDC may be used to power
devices with low current demands.
RS-485/422 COM0 and COM1 Pin Connections
COM0 and COM1 may also function as RS-422/485 ports. Table 3-5 contains descriptions for each
COM0 and COM1 pin for both 2-wire and 4-wire modes.
Note that the interrupt lines can be used to add interrupt capability to Opto 22 remote I/O units
connected to a G4LC32ISA-LT via an RS-485 serial link.
Table 3-5: Pin Descriptions for the RS-485 Serial Ports
Pin 2-Wire 4-Wire
1 Transmit/Receive Plus (TX/RX-) Transmit Plus (TX+)
2 Transmit/Receive Minus (TX/RX-) Transmit Minus (TX-)
3 Common Ground (GND) Common Ground (GND)
4 No Connection (NC) Receive Plus (RX+)
5 No Connection (NC) Receive Minus (RX-)
6 Interrupt Plus (IRQ+) Interrupt Plus (IRQ+)
7 Interrupt Minus (IRQ-) Interrupt Minus (IRQ-)
Wiring to a Host PC
This section provides information on wiring connections between a G4LC32ISA-LT’s COM0 port and
a host PC. This type of connection is used when multiple G4LC32ISA-LTs are multidropped over an
RS-485 network. Examples show connections to a standard PC serial port and an Opto 22 AC37.
Be sure to use cabling that is appropriate for your application. See Appendix B for a list of
recommended cables and connectors.
RS-232 COM0 and COM1
Figure 3-10 presents an example of RS-232 wiring between a host PC and the COM0 or COM1 port
of an G4LC32ISA-LT. Verify that the pin connections on your host PC are the same as those called out
in the diagram.
INSTALLATION AND SETUP