Signametrics Corporation SMU2060, Руководство оператора

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5.4 Windows DLL Default Modes and Parameters
After initialization, the Windows DLL default modes and parameters on your DMM are set up as follows:

Auto ranging: Off

Counter Auto Ranging: On

Function: DC Volts

Range: 240V

Relative: Off

Measurement Aperture:160ms

Read Interval: 0ms

Temperature units set to ºC

Offset Ohms: Off

In-Circuit Caps level: 0.45V Peak.

Source mode: OPEN_LOOP

Trigger polarity: Positive Edge

Sync output polarity: Positive

Sync output: Disabled

Fast RMS: off

Thermocouple type: ‘K’
5.5 Using the SMU2060 DLL with LabWindows/CVI
When using the SMU2060 DLL with LabWindows/CVI, you should read the LabWin.txt file included
with the software diskette.
An example application of SMU2060 DLL calls from LabWindows/CVI is shown below. It contains
functions
measure_ohms() and measure_vdc() , with sample calls to the SMU2060.
NOTE: Although these measurement functions use LabWindows/CVI and the LabWindows/CVI(R) Test
Executive, they are not necessarily coded to LabWindows instrument driver standards.
/* function: measure_ohms, purpose: measure 2-wire ohms */
int measure_ohms(double OHMreading) {
short ret, i;
DMMSetFunctions (0, OHMS2W);
DMMSetAutoRange (0, TRUE);
/* to settle auto-range and function changes ignore three readings */
for( i = 0 ; i < 4 ; i++ ) ret = DMMReadNorm (0, & OHMreading);
return ret;
}
/* function: measure_vdc, purpose: measure DC Volts */
int measure_vdc(double Vreading) {
short ret, i;
DMMSetFunctions (0, VDC);
DMMSetAutoRange (0, TRUE);
/* to settle auto-range and function changes ignore three readings */
for( i = 0 ; i < 4 ; i++ ) ret = DMMReadNorm (0, &Vreading);
return ret; }
5.6 Windows Command Language
The following section contains detailed descriptions of each function of the Windows command
language. Those commands that pertain to only the SMU2060 are indicated. Most functions return an
error code. The code can either be retrieved as a string using
DMMErrString function, or looked up in
the SMU2060.H header file. The USBDMMUser.h file contains all the pertinent definitions for the
DMM ranges functions etc. The following description for the various functions is based on “C” function
declarations. Keep in mind that the Windows DLL containing these functions assumes all
int values to be
windows 32bit integers (corresponds to VisualBasic long type). In C++, TRUE = 1 and FALSE = 0
(which is different from VisualBasic where True is –1 and False is 0).
Grayed out functions are either, untested or unimplemented.