Can i synchronize motion and adquisition without an encoder?

[Cubictec]

Hi, I using a PCI-6034 DAQ, and PCI-7344. Can I synchronize adquisition and motion without use an encoder..?
Thanks ..

[Jochen]

I assume that you are using open loop steppers with the 7344. Otherwise you would need an encoder anyway. Your question is not very specific but I also assume that you want to get analog data synchronized to the position of your axis.

In this case you could connect the step output signal of the 7344 to pin 38 (PFI7/STARTSCAN)of the 6034.
Now you need to configure the 6034 for a continuous data acquisition with external scanclock and you will get one scan each time the 7344 sends a pulse to the output.
This only works fine if you don't move faster than 200000 steps per second (maximum sampling rate of the 6034). The possible speed decreases when you increase the number of channels you want to sample (e. g. if you sample two channels the maximum speed would be 1000
00 steps/s). If your step rate is higher than that you need to use a counter on the 6034 to scale down the scanrate.

All other synchronization techniques like breakpoints or high speed capture mode require an encoder.

Regards,

Jochen Klier
Applications Engineering Group Leader
National Instruments Germany GmbH

[Cubictec]

Perfect!
The idea which you mention is excellent but my doubt is like rout the stepper output to the Scanclock of the DAQ by RTSI BUS and not externally. Because I have the cable from pci7344 to MID 7604 I do not have form to take this line.
Do you have any idea to do This?...


Thanks.

[Jochen]

In this case the signal connection is not trivial. It's not possible to route the step output signals to RTSI lines so you need to do an external signal connection.
The only possible solution would be a custom cable or the use of some kind of adapter and two motion cables. There are no standard components available for this task.
My best recommendation would be to add an encoder because you can route the encoder signals to RTSI.

Regards,

Jochen Klier
Applications Engineering Group Leader
National Instruments Germany GmbH