Advanced Instruments 3900, Руководство пользователя

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Serial Communication Port (Figure 6)
The serial port can reliably communicate over shielded cable up to 10
meters in length. Data is transmitted asynchronously as 1 start bit, 8
data bits, and 1 stop bit with no parity. Hardware handshaking is sup-
ported; XON-XOFF software handshaking may be selected by means of
the SETUP menu (see Setup).
The default serial data rate is 1200 bps (bits per second), though 300
bps and 9600 bps may alternatively be selected (see Setup).
Each message transmitted from the communication port is terminated
by the sequence, Carriage Return (0D Hex), Line Feed (0A Hex), Null
(00 Hex). For display purposes, most messages consist of less than 20
characters but longer messages, which scroll across the display, are
transmitted no differently.
The 3900 transmits a significant amount of information via the commu-
nication port. Almost every item of information displayed by the instru-
ment can be transmitted over the port, including test results, all error
messages, and most display data from the TEST menu.
The serial communication port conforms to the DTE EIA-232/V.24 (RS-
232) standard and its pin assignments are shown in table 2.
Reservoir Pump Pushbutton (Figure 6)
Used to control the heat transfer fluid pump to prime, flush and drain
the heat transfer fluid reservoir and cooling chambers.
Reservoir Drain Port (Figure 6)
Used with the quick-connect connector and short length of tubing sup-
plied, to drain and flush the heat transfer fluid cooling chambers.
Supervisor/operator Keyswitch (Figure 2)
The operator (horizontal) position of the supervisor/operator keyswitch
provides a means of locking out the setup, test and calibration functions
of the instrument to help prevent unauthorized changes.
Instrument Operation