Inline CTL101, Operation Manual

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©2002 - INLINE, Inc. CTL101 Operation Manual - V1.3 03/22/02
Serial Port Set-Up
Preprogrammed command functions can be sent via the RS-232 / RS-422 / RS-485 serial output
port. The CTL101 accepts serial commands from a control system, computer serial port or any
other device capable of sending out serial ASCII commands at compatible baud rates, and relays
the commands to the video equipment via the output port.
RS-232, RS-422 & RS-485 FORMATS
RS-232, RS-422 and RS-485 formats are physical interface standards for serial communication.
RS-232 is a full duplex operation that is typically used for short distances (up to 25’). RS-232
full duplex is the most common format and is limited to point-to-point applications (i.e. one
computer, one piece of equipment). It is not designed for the simultaneous usage of several units
or for sending serial information over very long cable lengths.
RS-422 and RS-485 formats can operate in both full and half duplex modes. In half duplex
mode, only one unit can transmit information at any given time. Therefore, other units in the
system will not respond until the initial transmission is concluded, and only one unit can respond
at any given time. Half duplex mode is preferred for applications involving multiple devices and
/ or communication along fewer lines.
Note: Configuring the CTL101 for full or half duplex serial port operation is discussed in the
Serial Port Control Section on pages 20 - 22.
Both RS-422 and RS-485 formats are designed for longer cable runs (actual lengths depend on
cable grade, capacitance and a number of other variables). RS-485 is recommended when
operating multiple units on a single line.
Reflections will sometimes occur when signals are sent over long cable runs
(in the RS-422 / RS-485 mode). If a system incorporates several units and /
or long control cable runs (while operating in full duplex mode), users can
minimize reflections by setting dipswitches 2 & 3 and /or 5 & 6 to the "1"
position (on the CTL101) and / or by engaging the termination resistors on
the units located at opposite ends of the control cable (see diagram on page
5). For half duplex applications, engage switch 2 and / or 5 only.
COMMUNICATION PROTOCOL
1 start bit 1 stop bit
8 data bits no flow control (factory default setting)
no parity check 9600 baud (factory default setting)
BAUD RATE SELECTION
The CTL101 has a factory default baud rate of 9600 bps and can communicate at baud rates from
1200 up to 115,200.
Note: The baud rate of the computer / A/V equipment must match the baud rate selected on the
CTL101 (both the input and output port are set to the same baud rate).
If communication is lost, use the default switch on the bottom of the
CTL101 to reset the unit to factory default (9600 baud).