1. Working with multichannel project on ADAU1701 I see that Biquad (2nd order filter, DP)(grow) uses the same (10) instructions as "2nd order filter" itself. Obviously no subroutine is called for "grow" blocks. (It might be architectural restriction of ADAU1701 - or its a bug?)
2. But from looking at the compiler output of the project we can see that every biquad' 10-instruction block has the same last line : "00 00 00 00 01" - which is supposedly NOP. My understanding is that it's possible for biquad to use 9 instructions (that what we see in resources file on wiki), but one extra command is still inserted.
Anyone can confirm that it works as it should and no improvement is possible? (it's sad to see up to 10% loss in avail instructions)