Re: 1 sec pulse

Hello Yin,




What DAQ board are you using?  You could use a counter to generate the 1 sec
pulse. (Help >> Find Examples >> Hardware Input and Output >>
DAQmx >> Generating Digital Pulses >> Gen Dig Pulse.vi)  If the pulse starts out high, then you will
not have a rising edge for analog acquisition. 
If you put an initial delay on the pulse, then you would have a rising
edge for data acquisition.




The analog input task is going to be triggered off the
rising edge of the counter.  This can be
done by changing the source of the trigger to the output of the counter.  Right-click on the I/O control and select I/O Name Filtering.   This should bring up a new window with a
check box for advanced terminals.  Once
this box is selected, you should be able to select Ctr0InternalOutput as
your source.  This will automatically
internally route the signals.  Now your
analog acquisition will start on the rising edge of your counter pulse.




There is a great example that demonstrates how to
synchronize two different tasks.  (Help
>> Find Examples >> Hardware Input and Output >> DAQmx
>> Synchronization >> Multi-Function >> Multi-Function-Synch
AI-AO.vi)  You want to make one task a
slave and the other task a master.  You
want to start the slave task then start the master task.