Signametrics
26
After initialization, the Windows DLL default modes and parameters on your DMM are set up as follows:
Auto ranging: Off
Function: DC Volts
Range: 240V
Relative: Off
Measurement Rate: 2rps
5.5 Using the SM2060 DLL with LabWindows/CVI
When using the SM2060 DLL with LabWindows/CVI, you should read the
LabWin.txt
file included with the
software diskette.
An example application of SM2060 DLL calls from LabWindows/CVI ® is shown below. It
contains functions
measure_ohms()
and
measure_vdc()
, with sample calls to the SM2060.
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 SM2060 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
SM2060.H
header file. The
DMMUser.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). TRUE
is 1 and FALSE is 0 (which is also different from VisualBasic where True is –1 and False is 0).
Grayed out functions are either, untested or unimplemented.
