Generate analog voltage output in multiple channels using DAQ 6363 frequencyb doesn't match.

[Robertop31]

Hi to every one!

What I need in my application is to be able to generate 3 differnet sinusoidal signals (5kHz) using 3 different channels of a DAQ 6363. The aim is to be able to switch on or switch off any of the signals while the others still working (remains stopped if they were stopped or remains actived if they were actived). I can no use the DAQ Assist block for doing it  so I'm trying with the configuration of the pictutre: 

The problem is that the frequency that I set in the block diagram, is not the one I'm measuring by an external oscilloscope, in fact it is much more smaller. 

With the waveform chart I can asure that the signal is being generated correctly but somthing may be happening at the time of writing it on the DAQ. I have already try to change the write block among its pull-down menu selector.

Any idea of how can I solve it?

Thank you in addvance 🙂

[santo_13]

1. You need to configure DAQmx Timing with appropriate sampling rate
2. To scale to 3 AOs, you need to use N Channel N sample version of the DAQmx Write API
3. You can have only one AO task, this means, all 3 AO channels must be part of the same task
4. You have to ALWAYS write data to ALL Channels in the task
5. So, you've to create a logic to get the channel to update from the user and update that channel in your 3 element waveform array (corresponding to each channel) and write this waveform array to DAQmx

[Kevin_Price]

Consult the shipping example for non-regenerating continuous voltage output.  Here are the key points:

1. You'll need to call DAQmx Timing to configure a sample clock for your task

2. You'll need to call DAQmx Write to put data into your task buffer *before* starting the task

3. All the stuff related to triggering is optional.  It isn't necessary to bring it over into your app.

-Kevin P