Scientists are starting to measure the "complexity" of consciousness

Interesting topic. Ultimately it may just boil down to "size", where the numbers depend on what aspect of a system you're looking at.

For example: a Pentium is much more complex than a 6502. It's a different class too: 32 bit, supporting virtual memory, various operating modes, a much more extensive instruction set, various on-chip caches, etc. Datasheet is a much bigger read.

But ultimately, it's just different # of transistors / mm^2 of silicon, # of pins on the IC package, clockspeed, lines of code needed to write an emulator, size of Verilog / VHDL file(s) to describe it.

If emulator is written in C, all you need is a C compiler in both cases. If hardware description comes as Verilog, software processing that into (for example) an FPGA bitstream would just need different amounts of time & RAM.

In this context, I'd be mostly interested in the size of the 'manual', read: the amount of documentation needed to describe a brains' operation, the size of a program that could emulate such a structure (and of course, what that structure would look like).

I suspect science is rapidly approaching the point where that 'manual' can be written, and 'mini-brain emulators' are just like other apps running on our computing devices.