DH Instruments COMPASS FOR MOLBOX, User Manual

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COMPASS

for molbox™ User’s Manual
Page 149
© 1998-2003 DH Instruments, Inc .
13.2.4.2 <INSERT SPECIAL CHARACTER>
Use the <Insert Special Character> button in the event a nonprintable ASCII
character is a required part of the remote command. When activated the <ASCII
Characters> window displays. Select <Hex> to select the character using the
hexadecimal value or <Decimal> to select based on the decimal value. Most
non-printable characters will display as a square, printable characters will display
as their actual ASCII values. Scroll to the desired character then press the
<Insert> button. The cursor will turn into a pencil that should be used to point to
the location in which the character should be inserted. Move the cursor to the
proper position in the command string, then click the mouse button.
Figure 86 . <Insert Special Character> Panel
13.2.4.3 <COMMAND TERMINATOR>
Defines how the instrument terminates command strings. The selections
available from the drop down list are carriage return,
<CR> , and carriage
line feed, <CR> + <LF> . The majority of instruments that support an RS-232 or
IEEE-488 interface use carriage line feed as the command terminator.
Refer to the instrument documentation for details.
13.3 RS-232 INTERFACE
RS-232 is one of the most widely used interface standards. At least one RS-232 port is built into every IBM
compatible computer. The interface connects two devices in a full duplex fashion so that both devices
can talk simultaneously. The connection requires that the RS-232 receive line of one device is connected
to the transmit line of the second device and visa versa. In addition to this connection, some devices
require the connection of “handshaking” lines to signal the beginning and the interface conversation.
To set up an RS-232 instrument, an RS-232 cable must be connected between the instrument and the
computer. The port on the computer must be specified along with the settings of the remote instrument.
The computer RS-232 port must be specified and the settings of the port must be adjusted to the settings
of the remote instrument.
COMPASS provides setup features to facilitate this step. Refer to the
instrument’s manual to determine how to retrieve the RS-232 settings.
13.3.1 RS-232 SETUP
If the remote interface selection is RS-232, the <RS232 Settings> screen must be used to
specify the specific setting information. The <RS232 Settings> screen is called up in
COMPASS by clicking any of the RS-232 settings displayed. Select the correct settings for
the device from the drop down lists and click <OK> when ready. All settings, with the
exception of the <COM Port> , are defined by the device that will use the interface. Refer to
the instruction manual of that device to determine these settings and make any necessary
selections for the interface to function in RS-232. The
<COM Port> selection should