I would like to assign a Z80 PIO chip to my homebrew Z80 "computer". Unfortunately, what I've recently noticed in the datasheet, chip version which I actually have: Z0842006PSC can handle max. 6 MHz only, while my CPU works with 16 MHz crystal (chip itself can handle up to 20 MHz). Does it really mean I have to reduce Z80 clock also to 6 MHz?
After quick research I can see that PIOs can generally run with slower frequencies than Z80s - most common versions are 4 or 6 MHz (I couldn't find anything faster than 10 MHz), while Z80 in majority are 20 MHz versions. I don't understand why such disproportion, like using PIO in the architecture often impose CPU speed reduction.
I don't want to limit the clock so drastically, maybe is there some workaround? I know there are chips e.g. MOS6522 but I don't believe they would fit better :)