Crestron
ST-COM
RS-232/422/485 COM Module
RS-232/422/485 COM Module:
ST-COM
Description
Functional Description
There are two Crestron RS-232/422/485 COM module configurations available:
ST-COM and STI-COM. All of the features are identical with the exception of input
power requirements and unit nomenclature. The ST-COM uses a power pack rated
for 120 VAC supply and the STI-COM uses a power pack rated for 220 VAC. Use of
the power packs are optional within a Cresnet system. For purposes of this
Operations Guide, the term ST-COM is used for either configuration, except where
noted.
The ST-COM is a device with two independent bidirectional serial ports that can
support RS-232, RS-485, or asynchronous RS-422-based communication. The unit
enables a system to overcome the distance limitations of serial communication. It can
be used as part of the Cresnet system or SmarTouch STS to add control for
additional serial devices such as video projectors or AV switchers. If part of the
Cresnet system, use of the power pack is optional.
Both ports of the ST-COM may be used to control a wide variety of RS-232,
RS-485, or asynchronous RS-422 controlled equipment. A variety of
communications parameters are supported. Valid parameters are as follows.
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Baud rates may be one of the following possible rates: 300, 1200,
1800, 2400, 3600, 4800, 6100, 7200, 9600, 14400, 19200, 28800,
38400, 57600, and 115200. When specifying the baud rate on a port, do
not use commas.
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Parity may be even, odd, none, or zero stick (parity bit always 0). When
specifying the parity use E, O, N, or Z, respectively.
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Data bits may be 7 or 8.
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Stop bits may be 1 or 2.
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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
Operations Guide - DOC. 5695A
RS-232/422/485 COM Module: ST-COM
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