Vaux Electronics Lattis 1600 Series Owner's Manual - page 25
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VC-232 Serial Port (EIA/RS-232)
The VC-232 Port is designed to connect directly to any computer or control system which has a standard RS-232
serial port. For the record, instead of RS-232 (RS stands for Recommended Standard), the proper term is actually
EIA-232 or EIA/TIA-232 (for the standards bodies concerned). However, the EIA/TIA designation never really
caught on, and virtually everyone retains the RS-232 terminology.
A cable (not supplied) is needed to connect the VC-232 Port to the control system or computer serial port. The VC-
232 Port is a DB-9 F (female) connector – the connector pinout is defined below. Typically, only three wires are
needed: TX, RX, and Ground. Depending on the setup of your control system serial port, you may need to connect
other signals before the port becomes active. If your serial port expects handshake inputs (on CTS, DSR, and/or
DCD), you may be able to either change your port configuration to ignore these signals, or you may provide the
appropriate signals from the Vaux VC-232 connector. The Vaux end does not need special treatment — the VC-232
handshake input pins (RTS and DTR) are not used. Pin-9 on the VC-232 port is a Vaux-Private signal, used with the
RS-232 daisy-chain cable for multi-switcher installations. Pin-9 should normally not be connected to anything,
although a PC serial cable may temporarily be connected, since this signal is the normally-unused Ring-Indicator
input to the PC, and will not affect either system.
Vaux systems communicate at 9600 baud (bits-per-second) using 8 bits of data, no parity, and one stop bit.
The serial port on the controlling computer must be configured according to its manufacturer’s instructions.
Information transfer between the controlling computer and the Vaux system is in the VauxProtocol format — a
Vaux-defined command language comprised of various commands and messages.
VC-232 Port (RS-232 Interface) (DB-9 F Connector):
Pin
Vaux Use
1
DCD (Data Carrier Detect)
Computer <— Vaux
“Active” level output *
2
RXD (Receive Data)
Computer <— Vaux
Data Out
3
TXD (Transmit Data)
Computer —> Vaux
Data In
4
DTR (Data Terminal Ready)
Computer —> Vaux
[not used]
5
Signal Ground
—
Signal Ground
6
DSR (Data Set Ready)
Computer <— Vaux
“Active” level output *
7
RTS (Request To Send)
Computer —> Vaux
[not used]
8
CTS (Clear To Send)
Computer <— Vaux
“Active” level output *
9
IRU (private Vaux signal)
DO NOT CONNECT
(special) **
•
Typical Connections: TXD, RXD, and Signal Ground.
•
Minimal Connections: TXD, and Signal Ground (commands only)
•
* One or more of CTS/DSR/DCD may need to be connected to your serial port, if expected.
•
** Pin 9 should not be connected to a computer serial port, as it is sometimes used for the Ring Indicator
(RI) input – the Vaux IRU (unmod IR) signal should be left open for proper system operation.
•
Pins listed as not used, are not connected (to anything) in the Vaux system.
•
The DB-9 shield rim (the “D”) is connected to signal ground.