DH Instruments COMPASS FOR MOLBOX, User Manual

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COMPASS

for molbox™ User’s Manual
Page 77
© 1998-2003 DH Instruments, Inc .
Table 22. DUT Definition Editor, [Read] Tab Fields
FEATURE DESCRIPTION
Output Type
(required drop
down list
selection)
Specifies what form of data will be acquired from the DUT. The available selections are:
•
Voltage/Current: The DUT outputs an electrical signal that will be acquired by the
<DUT Output DMM> specified in the System Configuration (see Section 10.2). The
output units must be: V, mV, A or mA when this selection is used. COMPASS
automatically makes the necessary conversions from the DMM’s output unit, (typically
V or A), to the DUT’s output unit. No command information is required as commands
are provided in the DMM Hardware Definition (see Section 10.3.4).
•
RS-232: DUT data is gathered directly over the DUT’s RS-232 interface.
The <Initialization Commands> will be issued during run mode initialization, then
the <Read Commands> will be repeatedly sent to obtain real time output from the
DUT. The <RS232 Settings> must be selected by clicking the field and making the
necessary selections. Information on commands required to read the DUT by RS-
232 must be provided. Review Section 13.3 for details on the requirements of RS-
232 data acquisition. This selection is normally used only when the DUT actually
outputs directly by RS-232. However, it can also be used in a variety of situations in
which the DUT does not directly output in RS-232 but the device used to read the
DUT has an RS-232 interface, for example to read DUTs through a conversion module.
•
IEEE-488: DUT data is gathered using the IEEE-488 interface provided by the
IEEE-488 card specified in the System Configuration (see Section 10.2).
The < IEEE-488 Address> must be entered before saving the DUT. Information on
the commands required to read the DUT by IEEE-488 must be provided. Review
Section 13.4 for details on the requirements of IEEE-488 data acquisition. This
selection is normally used only when the DUT actually outputs directly by IEEE-488.
However, it can also be used in a variety of situations in which the DUT does not directly
output in IEEE-488 but the device used to read the DUT has an IEEE-488 interface.
•
Frequency: The DUT output is a frequency that will be acquired using the
<Frequency Measurement> device selected in the System Configuration (see Section 10.2).
The output units of the DUT must be: Hz, kHz, MHz or s. COMPASS automatically
makes the necessary conversions from the frequency based output unit, (typically Hz)
to the DUT’s output units. No command information is required as commands are
provided in the frequency counter Hardware Definition.
•
Manual: DUT data must be entered manually in [Run Test] and [Run DUT] modes. No
command or interface information is required.
RS-232 Settings/
IEEE-488 Address
(conditional entry
field)
This is the interfacing information for a DUT whose output type is RS-232 or IEEE-488.
An entry in this field is only required if the <Output Type> in this tab is RS-232 or IEEE-488.
Initialization
Commands
(conditional drop
down list/action
button)
These are the commands needed to initialize a DUT whose <Output Type> is RS-232 or IEEE-488.
Click the <Edit> button to display the <Remote Command Editor> form (see Section 13.2).
Enter the desired commands then close the form. These commands will be issued during the
initialization process of
[Run DUT] and [Run Test] run modes when the DUT <Output Type> is
RS-232 or IEEE-488. If the DUT does not require a specific initialization this field is not used.
Refer to the DUT’s remote interface manual to determine whether initialization commands are
necessary. Possible initialization commands include: setting unit of measure, gas or range. If
initialization commands are needed, enter them in the remote command Editor. All commands
entered will appear in appropriate list box.
Read Commands
(conditional drop
down list/action
button)
These are the commands needed to read a DUT whose <Output Type> is RS-232 or IEEE-488.
Click the <Edit> button to display the <Remote Command Editor> form (see Section 13.2).
Enter the desired read commands then close the form. These commands are continuously sent
to the DUT in all run modes that use the DUT. Up to 10 commands can be issued as part of the
reading process, however only one command can be specified as the actual read command.
The actual read command is the command that causes the DUT to return its output value. The
actual read command is specified by the arrow next to the command, “
”. All commands
entered will appear in the appropriate list box.
Communications
Test
(action button)
This feature is used to test communication with a DUT whose <Output Type> is RS-232 or IEEE-488.
Press this button to send the <Initialization Commands> and <Read Commands> to the DUT.
A <Spy Window> will display with the command response information used (see Section 6.7.7).
This feature is designed to provide on the spot troubleshooting of the remote commands setup. If a
command is not properly entered or the response format is not correct, the problem should be visible
in the spy window. Use the
<Remote Communications> option for further troubleshooting (see Section 13.6).