HP Drive manual Define Error Checking, #ifndef checkErr #define checkErrfCall, Error =

Models: Drive

1 114
Download 114 pages 61.75 Kb
Page 25
Image 25

Define Error Checking

1Next define error checking for your program. First you will define a macro to catch the errors. It is better to define it once at the beginning of the program that to add the logic to each of your program statements. After the #include statements, type the following lines:

#ifndef checkErr

#define checkErr(fCall)

\

 

if (error = (fCall),

(error =

(error < 0) ? \

error : VI_SUCCESS))

\

 

 

{goto Error;} else error = error #endif

2Next you will type the following lines at the end of the program to handle any errors that occur:

Error:

if (error != VI_SUCCESS)

{

ViChar errStr[2048];

hp34401a_GetError (session, &error, 2048, errStr); printf ("Error!", errStr);

}

Note: Including error handling in your programs is good practice. This code checks for errors in your program.

Initialize the Instrument

1To initialize the instrument, add the following Initialize with Options function right after the variable declarations you added in the previous section

checkErr( hp34401a_InitWithOptions (“GPIB::23::INSTR”, VI_FALSE, VI_TRUE, “Simulate = 1”, &session));

This initializes the instrument with the following parameters:

GPIB0::23::INSTR as the Resource Name (instrument at GPIB address 23)

VI_FALSE Does not perform an ID Query

VI_TRUE Resets the device

Using IVI with Visual C++ 25

Page 25
Image 25
HP Drive Define Error Checking, #ifndef checkErr #define checkErrfCall, Error =, Goto Error else error = error #endif