MODEL 1000
3.4.4.4
CPU RS-485 Configuration
The RS-485 multi-drop interface is supported on all serial channels with the installation of the
optional "Chip Kit" (P/N 3-2350-115). A single kit is sufficient to configure two of the channels for
RS-485. RS-485 is a 2-wire, multi-drop interface where only one station at a time talks (transmits)
while all others listen (receive). The following illustrations show the correct jumpering, driver IC
installation, and I/O connector pin-out for each of the COM1 channels when used in RS-485 mode.
CPU COM1 RS-485 Configuration
CPU COM2 RS-485 Configuration
INSTALLATION AND SETUP
Figure 3-18. COM1 RS-485
Figure 3-19. COM2 RS-485
SEP 2005
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