Yes, if you want to use a microcontroller to do all the stuff the C64 did, including video and audio signal generation, well, it can be done (check out LFT's "c

Yes, if you want to use a microcontroller to do all the stuff the C64 did, including video and audio signal generation, well, it can be done (check out LFT's "craft" and "phazor" demos). But you'll need a considerably faster CPU.