I don't know, but it doesn't matter, just like it doesn't matter if the code on your computer is on a HDD or SSD.
> and where is the execution logic for it?
I don't know, but it doesn't matter either. It's a question about the workings of the computer, not of the software.
Electronic computers make it really easy to separate the software from the hardware, and make it easy to dump the software in some other representation in order to understand it. When I want to understand a piece of code, I read its source code, I don't care about whether it's an amd64 or an arm64 CPU and the details of the encoding unless I am working on a compiler.
With biological computers it's much harder to dump the software. But nevertheless, until people realize that this is what they should attempt, or research how it can be done, I feel we won't make any progress on the nature of consciousness.