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Memory Map: $0000-$0100 = ZERO PAGE $0100-$0200 = STACK $0400-$0800 = TEXT/GR PAGE0 $0800-$0C00 = TEXT/GR PAGE1 $0C00-$0fff = we use this as TEXT/GR offscreen buffer $1000-$1fff = 4k free $2000-$3fFF = HGR1 page ; note we never use HGR2 ($4000-$6000) $4000-$9600 = roughly 20k(?) $9600-$BFFF = DOS3.3 $C000-$FFFF = peripherals/ROM Largest can load from $4000 to $9600 = 22,016 Largest can load from $1000 to $9600 = 34,304 $4000-$C000 = 32768 C64: Apple II: Starring: Three pages page flipping. Hires colors subset of Lores so can replicate a blocky color image. Could in theory animate this at 60Hz. Also could flip between 4 pages, but need the 8k of HGR page2. For cycle-counting timing, jmp one into a bit $C055 instruction which is EOR $C0,X (4 cycles) Note, discover that the LORES and HIRES pages aren't exact matches for each other, even when using same color. Half-pixel off? E-mail: Half screen text, half 40x96 lores. Text is also interlaced top/bottom to create new chars (including some lowercase) on Apple II+ and before w/o lower case. Trouble as the built-in font is offset a frame on II vs IIe? Also annoyance, my GR compressor uses Grey2 (color $a) as encoding, which means can't use a GR image to hold plain black spaces (char $a0)