ADAU1701:  How many instructions?

Hello,

It's well known that some of the ADAU1701's 1024 instructions (at 48K sample rate) are needed for what's generally described as "overhead." Is there a better-defined answer for exactly how many must be left on the table? For example, a bug fix has resulted in one of the DSPs in the mixer we make to run 1015 instructions. The code compiles and the prototype I tried it in works fine. Is there any downside in running this close to the edge? I once thought that if the exported TxBuffer file shows a few NOPs (code 0x00, 0x00, 0x00, 0x00, 0x01), it's good to go. Yet in this case the 9 NOPs I see adds up to 1024 -- so apparently this doesn't reflect the overhead either. It would be good to know what's involved with this "overhead."

Edit: I just reworked some logic in an attempt to shrink the project. What I had thought was quite clever saved me exactly one instruction. It's down to 1014 now.

Thanks, Bob

Audio Signal Processors

instructions

overhead

SigmaDSP Audio Processors

adau1701