“The 1541U2 provides two 8 channel SIDs and 8 PCM channels”
it provides two SIDs, regular 3 channels each. the PCM stuff is an extension indeed.
“Just because the Ultimate 64 is a C64 and the Mega65 is an enhanced C65, is that sufficient reason to say there should be absolutely no attempt to try to achieve some kind of compatibility between sound playback on both boards?”
comparing the c65 mode with c64 emulators is simply pointless, those are two totally different - and very likely incompatible, things. if the MEGA65s C64 mode is aiming to be half compatible, it cant extend the platform much over what is available as regular extensions to a real C64.
“Should Gideon refrain himsef from implementing registers to tune the HDMI picture, just because he is developing a C64 board?”
since HDMI supports 50/60Hz pictures perfectly, i dont even see any reason why this would be necessary :)
that said, those demanding all those fancy things are not the ones who will write software for it - and those who are writing software focus on the real C64 and some of its extensions. which is good in my book :)
edit: oh i see, U2 actually has those 8 voices. in all the years of owning (3 by now) 1541U i never realized that - nor cared :) demonstrates quite well how much programmers want to use this kind of thing - not a single program exists (correct me if i am wrong)