Can Signal Detection block be modified for smaller trigger time?

Hello J3627,

This block is designed to send a flag (1) when you have to turn off external circuits when no input is active. so, when no input is present (configurable threshold) for particular time (configurable time) then it will send a '1' to alert other systems/external devices to turn off.

'This flag can be used, for example, to alert a microcontroller that no audio signal is present in the signal chain, which could then allow the microcontroller to power-down unneeded parts of the system'

So, you want the other way then just use a zero comparator like below.

Regarding the time,

Try to overwrite the time constant parameter in the capture window. For the Sigma100 and 200 cores, the ADAU1701, 1401, 1761, 1442, 1787 uses a time constant formula as a leakage value to multiply by to obtain a time constant. The formula is given in this post.

Below is the location

Regards,

Harish

Yeah I used a Zero Comparator to reverse it. But that uses resources and doesn't get cancelled out during compilation, right?

Hand-modifying the parameters works, though I used a different formula.

0.1 sec = 0.998844488 seems like a nice value for an indicator LED.

Is there some way to make this coefficient persistent though? Every time I compile the project it gets overwritten.

Ideally you could modify the component to support a wider range of inputs.

Is it not possible to modify the block source code to support a smaller trigger time?

Hello J3627,

Unfortunately, we are not actively updating any of the code for this very old DSP. It still is a hugely popular DSP so if it were up to me, we would be still releasing updates. This DSP cannot write to its own parameter RAM so it is not possible for the program to update the parameter value. If you have a controller in your system then it can overwrite the value that the compiler stuffs into the time_constant parameter and change the trigger time. I do not have the formula handy and I did spend several hours yesterday trying to figure out and I even asked one of the programmers. But, I was able to write to the parameter in SigmaStudio and shorten the trigger time so it is possible.

Dave T

Yes I was already able to change the parameter value in SigmaStudio but that's going to be fragile for production so I replaced the block with different ones.

So the SigmaDSPs are considered "old" and the software won't be maintained anymore? NRND?

Hello

I am not hiding that SigmaStudio 4.7 has not been updated in a long time. We are developing SigmaStudio+ actively but the 1701 that was released in 2007 at the moment is not supported in SS+. The SigmaDSPs are SUPER popular and SigmaDSP cores are in so many new products but the history is this. The ADAU1701 is one of the early ones but it is still one of our best selling SigmaDSP parts!! Because it is so great and so handy. I have been internally yelling for us to support this processor with SS+ and it may very well happen but at the moment do not expect any update of SigmaStudio 4.7 or for the 1701 to be included in the SigmaStudio+ software.

The ADAU1701 will not go NRND any time soon!! Like I said, it is our second best selling part behind the Sigma300/350 parts.

Feel safe to design this into any long term product you are thinking of. The only bummer is if you need a new block or a bug fix it will not happen. However, that said, if you are going to buy a very large volume of these we may be able to do something custom. These efforts have to be justified up the management chain that I am sure you understand.

Dave T

Second best selling part, but the only software that works with it is buggy and undocumented and unmaintained?