/*********************************************************************
*
* ANSI C Example program:
* ContThrmcplSamps-IntClk.c
*
* Example Category:
* AI
*
* Description:
* This example demonstrates how to make continuous, hardware-timed
* temperature measurement using a thermocouple.
*
* Instructions for Running:
* 1. Specify the Physical Channel where you have connected the
* thermocouple.
* 2. Enter the Minimum and Maximum temperature values in degrees C
* you expect to measure. A smaller range will allow a more
* accurate measurement.
* 3. Enter the scan rate at which you want to run the acquisition.
* 4. Specify the type of thermocouple you are using.
* 5. Thermocouple measurements require cold-junction compensation
* (CJC) to correctly scale them. Specify the source of your
* cold-junction compensation.
* 6. If your CJC source is "Internal", skip the rest of the steps.
* 7. If your CJC source is "Constant Value", specify the value
* (usually room temperature) in degrees C.
* 8. If your CJC source is "Channel", specify the CJC Channel
* name.
* 9. Specify the appropriate Auto Zero Mode. See your device's
* hardware manual to find out if your device supports this
* attribute.
*
* Steps:
* 1. Create a task.
* 2. Create a Thermocouple (TC) temperature measurement channel.
* 3. If your device supports Auto Zero Mode, set the AutoZero
* attribute for all channels in the task.
* 4. Call the Timing function to specify the hardware timing
* parameters. Use device's internal clock, continuous mode
* acquisition and the sample rate specified by the user.
* 5. Call the Start function to program and start the acquisition.
* 6. Read N samples and plot it. By default, the Read function
* reads all available samples, but you can specify how many
* samples to read at a time and the timeout value. Continue
* reading data until the stop button is pressed or an error
* occurs.
* 7. Call the Clear Task function to clear the Task.
* 8. Display an error if any.
*
* I/O Connections Overview:
* Connect your thermocouple to the terminals corresponding to the
* Physical Channel I/O Control value.
*
*********************************************************************/
#include <stdio.h>
#include <NIDAQmx.h>
#define DAQmxErrChk(functionCall) if( DAQmxFailed(error=(functionCall)) ) goto Error; else
int32 CVICALLBACK EveryNCallback(TaskHandle taskHandle, int32 everyNsamplesEventType, uInt32 nSamples, void *callbackData);
int32 CVICALLBACK DoneCallback(TaskHandle taskHandle, int32 status, void *callbackData);
int main(void)
{
int32 error=0;
TaskHandle taskHandle=0;
char errBuff[2048]={'\0'};
/*********************************************/
// DAQmx Configure Code
/*********************************************/
DAQmxErrChk (error=DAQmxCreateTask("task1",&taskHandle));
//DAQmxErrChk (DAQmxCreateAIThrmcplChan(taskHandle,"","",0.0,100.0,DAQmx_Val_DegC,DAQmx_Val_J_Type_TC,DAQmx_Val_BuiltIn,25.0,""));
DAQmxErrChk (error=DAQmxCreateAIThrmcplChan(taskHandle,"Dev1/ai0","",0.0,100.0,DAQmx_Val_DegC,DAQmx_Val_J_Type_TC,DAQmx_Val_BuiltIn,25.0,"ai0"));
//DAQmxErrChk (DAQmxCfgSampClkTiming(taskHandle,"",10.0,DAQmx_Val_Rising,DAQmx_Val_ContSamps,1000));
DAQmxErrChk (error=DAQmxCfgSampClkTiming(taskHandle,"",10,DAQmx_Val_Rising,DAQmx_Val_ContSamps,1000));
// DAQmxErrChk (error=DAQmxCfgImplicitTiming (taskHandle, DAQmx_Val_FiniteSamps, 1000));
DAQmxErrChk (error=DAQmxRegisterEveryNSamplesEvent(taskHandle,DAQmx_Val_Acquired_Into_Buffer,1000,0,EveryNCallback,NULL));
DAQmxErrChk (error=DAQmxRegisterDoneEvent(taskHandle,0,DoneCallback,NULL));
/*********************************************/
// DAQmx Start Code
/*********************************************/
DAQmxErrChk (DAQmxStartTask(taskHandle));
printf("Acquiring samples continuously. Press Enter to interrupt\n");
getchar();
Error:
if( DAQmxFailed(error) )
DAQmxGetExtendedErrorInfo(errBuff,2048);
if( taskHandle!=0 ) {
/*********************************************/
// DAQmx Stop Code
/*********************************************/
DAQmxStopTask(taskHandle);
DAQmxClearTask(taskHandle);
}
if( DAQmxFailed(error) )
printf("DAQmx Error: %s\n",errBuff);
printf("End of program, press Enter key to quit\n");
getchar();
return 0;
}
int32 CVICALLBACK EveryNCallback(TaskHandle taskHandle, int32 everyNsamplesEventType, uInt32 nSamples, void *callbackData)
{
int32 error=0;
char errBuff[2048]={'\0'};
static int totalRead=0;
int32 read=0;
float64 data[1000];
/*********************************************/
// DAQmx Read Code
/*********************************************/
DAQmxErrChk (DAQmxReadAnalogF64(taskHandle,-1,10.0,DAQmx_Val_GroupByScanNumber,data,1000,&read,NULL));
if( read>0 ) {
printf("Acquired %d samples. Total %d\r",read,totalRead+=read);
fflush(stdout);
}
Error:
if( DAQmxFailed(error) ) {
DAQmxGetExtendedErrorInfo(errBuff,2048);
/*********************************************/
// DAQmx Stop Code
/*********************************************/
DAQmxStopTask(taskHandle);
DAQmxClearTask(taskHandle);
printf("DAQmx Error: %s\n",errBuff);
}
return 0;
}
int32 CVICALLBACK DoneCallback(TaskHandle taskHandle, int32 status, void *callbackData)
{
int32 error=0;
char errBuff[2048]={'\0'};
// Check to see if an error stopped the task.
DAQmxErrChk (status);
Error:
if( DAQmxFailed(error) ) {
DAQmxGetExtendedErrorInfo(errBuff,2048);
DAQmxClearTask(taskHandle);
printf("DAQmx Error: %s\n",errBuff);
}
return 0;
}
