Blackfin Data Type question

[Sreekar]

Hi,

I've been using Labview Embedded software for Blackfin targeting the Blackfin 537 EZ lite kit. I have a basic question with regards to Labview dealing with Blackfin data types. I have an example code screenshot attached which gives a better idea about my question. The actual icons do not appear beacuse this machine does not have the mbedded software but regular labview software but I hav ethe name of the functions that I used. Basically, was trying to use this for simpl audio signal processing but for me to do any processing I need to understand the data type. So if you see the 'BF Seperate Audio channels.vi'(highlighted in red) it has a left and right output. So if i just passs these to the inputs of 'BF Combine audio Channel.vi'(highlighted in green to the right) I can hear the audio good but if I do any kind of math to these lines the output is noisy and inexplicable. I would like to know waht type of data this is and what i need to do for som math manipulation (For Eg. multiply to amplify the volume and divide to reduce the volume etc.)

Thanks,

-Sreekar

[Nadim R]

Hi Sreekar,

Here is a great Developer Zone article relating the supported data types on the BF processor.  I think you might be facing floating point emulation, which is slowing down your application.  Applications that require processor-intensive real-time signal processing, such as real-time audio processing, where the overhead of the floating-point emulation library is too great, you may face application slowdown.  For those applications, you must convert your algorithm to a fixed-point implementation.

I hope this helps,

Regards,

Nadim
Applications Engineering
National Instruments