Kind of off topic for 6502 memory copy speeds but with regard to scrolling, there became a pretty cool software hack for the C64 (called VSP) where you could tr

Kind of off topic for 6502 memory copy speeds but with regard to scrolling, there became a pretty cool software hack for the C64 (called VSP) where you could trick the poor VIC chip into starting scanning out the screen position later in memory. Move the start one character and the whole screen shifts left by 8 pixels. You only need to repaint a vertical column for this 'course' scroll instead of moving the entire screen of characters. This is something that should have been built into the hardware and was very useful on other systems that had that ability (like the NES for example) With it you can reduce the amount of memory you need to copy every 8 pixels (the 8 pixel part can be done with smooth scroll registers). There's a thread and example code on github here. https://www.lemon64.com/forum/viewtopic.php?t=70539 https://www.lemon64.com/forum/viewtopic.php?t=70539 Also note it's such a terrible hack on the DRAM that it doesn't work on all C64s and there's a technical discussion about that here. https://www.linusakesson.net/scene/safevsp/index.php https://www.linusakesson.net/scene/safevsp/index.php Hardware mod if VSP doesn't work on your C64 and more technical details. http://wiki.icomp.de/wiki/VSP-Fix http://wiki.icomp.de/wiki/VSP-Fix Also it makes mention of the C64-Reloaded which is a modern C64 product that includes the fix.