Serial Interface Manual
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TLS2 Monitoring Systems
Part No. 577013-767, Revision H
2
2.2
EIA RS-232 INTERFACE
The EIA RS-232 interface is designed to connect to modems for transmission of data over telephone
lines. It can be used for direct local attachment of terminals if the cable run is no more than 50 feet. In
practice, cable runs longer than 50 feet have performed satisfactorily; however, since the RS-232
specification is designed for operation up to 50 feet, direct connect cable runs greater than 50 feet are not
warranted for proper operation.
3.0
CHARACTER FORMAT AND BAUD RATE
The system receives and sends characters via the RS-232 interface in an ASCII format that is configured
via the system front panel keypads. Selections consist of: 1 start bit; 7 or 8 data bits; odd, even or no
parity; and 1 or 2 stop bits. Communications rate is selectable: 300, 1200, 2400, 4800, or 9600 baud.
The system operates in a full duplex mode. Characters are not echoed when received, and transmitted
characters must not be echoed back to the system. Transmit and receive can occur simultaneously, and
commands can be stacked in the system buffer (up to 128 characters).
4.0
SECURITY CODE SETTINGS
A security code can be enabled for each port from the front panel setup menus, or by using the
appropriate serial commands. Each port has its own security code which is enabled and set
independently. When a security code is enabled for a given port, it must be used in any commands
transmitted to that port, in accordance with the format shown below, or else the console will not respond
to the command.
