Fantastic work! I've been checking on here every few days over recent months in anticipation, and was quite excited today to see your posts. I'll certainly be reading through them in detail over the next few days and weeks.

I considered reverse engineering the 6522 a couple of times in the past ...

It sounds like I have been drawing around the polysilicon and diffusion in the right way then. I started out like that mainly due to how the Mead/Conway book presented things. Good to know then that this appears to be how things are normally done. I do wonder though whether the polygons I have been ...

I hope people don't mind me resurrecting a topic I posted over 5 years ago. Only my 4th post, but I wanted to bring people's attention to a series of posts I've made over at the VIC 20 Denial Forums regarding reversing the logic of the 6561 VIC die shot:

http://sleepingelephant.com/ipw-web/bulletin ...

Thanks Ed. That is very helpful. It might take me a few days to look over this in detail. I may well have some additional questions.

What I might try to do is recreate the physical layout for this 8 bit register inside the Electric VLSI tool. That seems like as good a way as any of keeping track ...

Let's give this a go. It is probably one of the more cluttered parts of the die shot, but I think in this case we know what should be here. It is apparently register CR2, so I'm guessing that there is an 8-bit flip flop in there somewhere. Those 8 short vertical metal lines look suspiciously related ...

I was wondering if anyone here would be able to help me get my feet wet in understanding the die shot for the 6561 VIC video chip as downloadable from the visual6502.org web site:

http://visual6502.org/images/pages/MOS_6561_VIC_die_shots.html

I've been staring at it for a couple of weeks now and ...