Hi all,
I am wanting to sample a pulse and a sine wave at a low frequency of 1 kHz point by point sampling and upon a condition being met - the leading edge of the pulse being greater than a certain value - I the want to take a certain number (here 270) of samples of the sine wave at 50 kHz, multiple samples. I am doing this within a case structure and using a separate DAQ card.
The problem is that when the conditon is met is does not capture the data at the higher frequency straight away. It misses part of the sine wave before commencing capturing the 'window' of the 270 samples of the sine wave at 50 kHz. I want to know if there is any way of speeding this up? I am aware that using an FPGA could help but I don't have access to one.
The other solution would to advance the condition, i.e advance the pulse train by a certain amount so that I compensate for the delay in activating the high freq capture. I would need to set up this advance of the pulse train so that, after the delay in activation, it captures the data exactly where it is required to. What would be the best way to do this? I could delay the pulse train by a certain number of samples/ or delay the sine wave, or I have read that you can use the sample timer/counter within the DAQ card to change the 'trigger of the pulse train'. How would I implement this?
Attached is my vi. I would be very appreciative if you could help.