DH Instruments COMPASS FOR MOLBOX, User Manual

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COMPASS

for molbox™ User’s Manual
Page 113
© 1998-2003 DH Instruments, Inc .
FEATURE DESCRIPTION
Set Units
(drop down
selection list)
Indicates whether the <Set Commands> are for setting voltage (V) or current
(A).
Separate <Set Commands> are set up for reading voltage (V) and current
(A) in the same profile so that COMPASS can set in either mode as
required by the current flow controlling device.
The <Set Commands> specified are the commands for setting power in the
<Set Units>. COMPASS always makes the necessary conversion to this
unit before sending the set command.
Remote
Interface
(drop down
selection list)
The choices available are <RS232> and <IEEE-488> . To set up the device for
remote communications, select the interface that is on the device. When an
interface type is selected, the rest of the
<Remote Interface> and <Command
Information> panels change as appropriate to accommodate definition of the
interface characteristics. A remote interface selection is required. COMPASS
generates an error when <None> is selected.
RS-232
Settings
(conditional
display panel)
If the remote interface selection is RS-232, the <RS232 Settings> information is
shown. When creating a new device, the settings are loaded with COMPASS
default settings. Port settings are listed: baud rate, parity, data bits, stop bits.
Clicking on any setting field causes the <RS232 Settings> Editor to appear
(see Section 13.3.1). Select the correct settings for the device and click <OK>
when ready.
IEEE-488
Address
(conditional
entry field)
If the remote interface selection is IEEE-488, the <IEEE-488 Address> entry
field is shown. When creating a new Definition, the IEEE-488 address is set to
the default address 10. The address can be edited directly in the entry field.
Initialization
Commands
(action button)
Click this button to display the <Remote Command Editor> form (see
Section 13.2.1). Enter the desired commands then close the form.
These commands are issued during the initialization process if required by the
selected device. The device may or may not require a specific initialization.
Refer to the device’s remote interface manual to determine whether initialization
commands are necessary. Some devices may require a unit of measure and
range selection before being used. If this is the case, and the device has the
necessary commands to complete this task, enter the commands in the remote
command Editor.
Set Commands
(action button)
Click this button to display the <Remote Command Editor> form (see
Section 13.2.3). Enter the desired set commands then close the form.
Set commands typically require the <Set Unit Variable> to specify where the
numerical target flow information should be located in the command string.
Enter the command string then
drag and drop or type the <Set Unit Variable>
text into the appropriate location in the command string. COMPASS substitutes
the current numerical set point in the <Set Units> with the <Set Unit Variable>
to create the final set command. This command is sent as needed to control the
flow when tests are run. Up to 10 commands can be issued as part of the set
flow process.