Gladly! Sorry if it's a bit hard to follow, trying to snip out relevant parts without posting the whole program. Not sure if you want to see the configuration stuff, it's just setting up a few analog input channels in the same task. Basically I want to be able to display the readings from the measurement devices on screen, then start recording data once we actually start the experiment.
float64 *data=NULL; //data array
//This is the callback for the toggle button to collect data
int CVICALLBACK SHOW_VALUES (int panel, int control, int event,
void *callbackData, int eventData1, int eventData2)
{
switch (event)
{
case EVENT_COMMIT:
GetCtrlVal(TabPanelHandle, MTAB_DISPLAY,&running); //Toggle switch to start collecting data
if (running ==1)
{
StartTasks(); //Calls the function to start the tasks
if( (data=malloc(AIavg*numChannels*sizeof(float64)))==NULL ) //Allocates memory to the data array
{
MessagePopup("Error","Not enough memory");
}
}
if (running ==0)
{
StopTasks(); //Calls the function to stop the tasks
}
while (running)
{
ReadData();
ProcessSystemEvents();
}
break;
}
return 0;
}
// Function to read data
void ReadData(void)
{
DAQmxReadAnalogF64(analoghandle,AIavg,10.0,DAQmx_Val_GroupByChannel,data,AIavg*numChannels,&numRead,NULL);
}
//Then there's another function to toggle whether or not the data is recorded
int CVICALLBACK RECORD_DATA (int panel, int control, int event,
void *callbackData, int eventData1, int eventData2)
{
switch (event)
{
case EVENT_COMMIT:
GetCtrlVal(TabPanelHandle, MTAB_DISPLAY,&recording);
if (recording ==1)
{
if (initial ==0) //I put this in so that it only does the TDMS configuration once
{
ConfigureData();
}
}
while (recording ==1 && initial==1) //Makes sure that streaming doesn't begin until after file configuration
{
gStop = FALSE;
WriteData();
Delay(AIavg/AIrate);
ProcessSystemEvents;
ProcessDrawEvents;
}
if (recording ==0)
{
TDMS_CloseFile (0);
initial=0;
}
break;
}
return 0;
}
//This does the TDMS file configuration
void ConfigureData(void)
{
channels = malloc (sizeof(TDMSChannelHandle) * numChannels);
TDMS_CreateFile (filename, TDMS_Streaming, FILE_NAME, FILE_DESC, "", "", &file);
TDMS_AddChannelGroup (file, GROUP_NAME, GROUP_DESC, &group);
for (chan = 0; chan < numChannels && !gStop; chan++)
{
sprintf (channelName, "channel%d", chan);
sprintf (channelDesc, "Data for channel %d", chan);
TDMS_AddChannel (group, TDMS_Double, channelName, channelDesc, 0, &channels[chan]);
}
initial =1;
return;
}
void WriteData (void)
{
TDMS_AppendDataValues (channels[0], data, 3*AIavg, 1);
}
