Cnx Rs-232/422/485 Expansion Card: Cnxcom-2; Description; Functional Description - Crestron CNXCOM-2 Operation Manual

CNX RS-232/422/485 Expansion
Card: CNXCOM-2

Description

Operations Guide - DOC. 8123
CRESTRON

Functional Description

The CNXCOM-2 RS-232/422/485 Expansion Card provides RS-232, RS-422, or
RS-485 communication with hardware and software handshaking. Speeds are rated
up to 38,400 bps. In fact, a variety of communication parameters are support. Valid
parameters are as follows.
Baud rates may be one of the following possible rates: 300, 600, 1200,
2400, 4800, 9600, 19200, and 38400.
Parity may be even, odd, none, or zero stick (parity bit always 0).
When specifying the parity use E, O, N, or Z, respectively.
Data bits may be 7 or 8.
Stop bits may be 1 or 2.
Both XON/XOFF handshaking and RTS/CTS handshaking are
supported. XON/XOFF handshaking may be supported by specifying
XON (for both transmit and receive), XONR (for receive only), or
XONT (for transmit only). XON/XOFF and RTS/CTS handshaking
are mutually exclusive in the CNXCOM-2. If both are enabled,
RTS/CTS is used. If CTS handshaking is enabled, the CTS line is
monitored by the CNXCOM-2. The CTS line can also be enabled as a
digital input to the control system; the RTS line can be enabled as a
digital output.
Specify RS422 for standard if RS-422 compatible levels must be
supported.
Break character of any length can be generated.
Supports RS-485. However, a specific protocol for defining the
mechanism as to when a device is permitted to transmit on the RS-485
bus must be followed. To use this feature, use RS-422 communications
settings. Set hardware handshaking to none. The RTS output can now
be used to enable the transmitter. Notice that the receiver is always
active. Therefore, transmissions are also received.

CNX RS-232/422/485 Expansion Card: CNXCOM-2

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