American Magnetics 286 Multi-Sensor Liquid Level Instrument (CE-Marked) User Manual
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Remote Interface Reference
RS-232/422 Configuration
page 55 for illustration of the menu provided for configuring the baud rate
of the Model 286 serial interface.
The Comm Menu provides menus to configure the baud rate (the default is
shown in bold). All additional parameters are fixed:
•
Baud Rate: 1200, 2400, 4800, 9600
•
Parity and Data Bits: No Parity/8 Data Bits (fixed)
•
Number of Start Bits: 1 bit (fixed)
•
Number of Stop Bits: 1 bit (fixed)
•
Flow Control: None (fixed)
5.3.1
Serial Port Connector
An IBM-compatible computer’s serial port can be directly connected to the
Model 286 via a standard DB25 female-to-DB9 male PC modem cable if
the Model 286 is configured for RS-232. Refer to your computer’s
documentation to determine which serial ports are available on your
computer and the required connector type. If a DB9 connector is required
at the computer interface, the connector translation is provided in the
Appendix.
The Model 286, when configured for RS-232, uses only three wires of the
rear-panel DB9 connector: pin 2 (receive), pin 3 (transmit), and pin 7
(common). The RS-232 pinout is fully documented in the Appendix. The
Model 286 is classified as a DCE (Data Communication Equipment) device
since it transmits data on pin 3 and receives data on pin 2. The computer
or terminal to which the Model 286 is attached must do the opposite, i.e.,
transmit on pin 2 and receive on pin 3 (the requirements for a DTE, or
Data Terminal Equipment device). If a serial-to-parallel converter is used,
it must be capable of receiving data on pin 3 or the cable connected to the
Model 286 must interchange the wires between pins 2 and 3.
Optional RS-422 connector pinout is provided in the Appendix.
5.3.2
Termination Characters
All commands and queries are transmitted and received as ASCII values
and are case insensitive. The Model 286 always transmits
a carriage return followed by a linefeed) at the end of an RS-232
transmission. The Model 286 can accept
computer.