ASIO interface for LabVIEW

[leemkuny]

Thanks again for fast response.

I had to make one slight change to 'ASIO_Get_Single_Device_Info.vi' which refers to a missing subVI.

I copied code from previous revision which works.

I'll test the new functionality and get back to you. It may be a few days before I get to it.

Cheers, Liam.

[leemkuny]

LVcoder,

Retrying the 'save for previous version' as v14 files. I believe my mistake was clicking save when closing the file after 'save for previous version' overwrites the files as v24. These files are not tested with your new dll.

Hope this works, Liam.

[LVCoder]

oops apologies for the missing vi. Attached is the fixed version of the library

[leemkuny]

Hi LVCoder.

Sorry to report that the new code is not working for buffer sizes other than the default. 

Below is a screenshot from your 'ASIO_Input_Output_LV.vi' with buffer size = 512. All looks and sounds good. 

However if I change buffer size to 256 I get a distorted output waveform. The sinewave appears to be switching on and off. This is heard on the output and recorded on input with loopback. 

The output wave appears to repeatedly switch on for 54 samples and off for 202.  

Can you check if this is the same with your setup? 

Cheers, Liam.

[LVCoder]

Hi Liam,

What ASIO device drivers are you using? Is it ASIO4all? If so, you'll also need to adjust the buffer size in the ASIO4all control panel.

I don't have any Behringer devices with me to test. Still, I have tested different buffer sizes on Komplete Audio, and it works fine as long as I set the same buffer size in the Native Instruments Komplete Audio Control Panel as I set in my LabVIEW app.

[leemkuny]

Hi LVCoder,

I really do appreciate your continued support on this. 

So the UMC404HD has it's own 'UMC ASIO Driver'. It does not use 'ASIO4All'.

I was able to modify the buffer size using the preferences in another app (Reaper) and when I do so this value becomes the 'preferred buffer size' as seen in 'Device Info' in your LV code. I can match this value using 'ASIO_LV_set_buffer_size.vi' and yes this works, also reducing the the latency. e.g. with buffer size = 128...

All is good - almost!

Rather than having to use a 3rd party app, is it possible for labVIEW to actually set the buffer size?

If not, the 'ASIO_LV_set_buffer_size.vi' is redundant as you have to match the 'preferred buffer size' as set by the 3rd party for it to work.

Cheers, Liam.

[LVCoder]

Hi Liam,

ASIO SDK doesn't allow changing the buffer size programmatically on the hardware. It needs to be done using the ASIO driver control panel. 

I have added a button on the front panel to open the selected driver's control panel, allowing the user to change the buffer size within it. 

Now you won't have to go to a third-party app like Reaper to open the control panel; you can open it directly from LV and change the settings you desire.

Attached is the latest code.

[leemkuny]

That works. Thanks!