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4 examples using visual basic, Examples using visual basic -12 – KEPCO KLR Series Developers Guide User Manual

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3-12

KLR-DEV 060713

The functions above used a function checkErr which is part of the project file KpDCPwrEr-
rorHandler.c
. This file has calls to two functions: KpDCPwr_GetError and
KpDCPwr_error_query. These two functions check for errors and provide readable text of the
error messages.

KpDCPwr_GetError(vi, &errorCode, bufferSize, pos);
// Display the error from the instrument, if that is the source
if (errorCode == KPDCPWR_ERROR_INSTRUMENT_STATUS)
{
KpDCPwr_error_query(vi, &errorCode, buffer);
}
MessagePopup("Error!", buffer);

3.4

EXAMPLES USING VISUAL BASIC

The following paragraphs are example of how to use code written in Visual Basic to set the out-
put and take a measurement, and how to use a list to perform as series of operations

3.4.1

SETTING THE OUTPUT TO A VALUE AND TAKING A MEASUREMENT

The following example, written in Visual Basic, sets the output to a value and then takes a mea-
surement. The filename for this example is VBOutputExample.txt, located in the ivi\driv-
ers\kepco\examples folder (see Figure 3-3 for complete code).

Note that Visual Basic has its own methods to support the IVI-COM driver.

Public driver As KepcoDCPwr
Public outputPtr As IKLROutput
Public protectionPtr As IKLRProtection
Public measurementPtr As IKLRMeasurement

Set driver = New KepcoDCPwr

Once the driver is initialized, the connection between host and KLR is established using a stan-
dard VISA resource string. It is important that the initialize function be passed as true since its
second argument allows KLR-specific features to be enabled, however in this example, no KLR-
specific feature such as list is required.

' initialize the driver - note ID device is true
driver.Initialize "GPIB0::6::INSTR", _
True, _
True, _
"Cache=true,InterchangeCheck=false,Query-

InstrStatus=true,Simulate=false"


Dim result As Boolean
result = driver.Initialized

Set outputPtr = driver.Outputs.Item(driver.Outputs)
Set protectionPtr = driver.Protections.Item(driver.Protections)
Set measurementPtr = driver.Measurements.Item(driver.Measurements)