xxl Posted July 20, 2022 Share Posted July 20, 2022 https://github.com/einar-saukas/ZX1 soon on the website I will add sources for use https://xxl.atari.pl/ conan.gfx: 7680 ZX0: 1625 ZX1: 1671 ZX5: 1532 zx1-gfx.obx 6 Quote Link to comment Share on other sites More sharing options...
dmsc Posted July 20, 2022 Share Posted July 20, 2022 Hi! 1 hour ago, xxl said: https://github.com/einar-saukas/ZX1 soon on the website I will add sources for use https://xxl.atari.pl/ conan.gfx: 7680 ZX0: 1625 ZX1: 1671 ZX5: 1532 zx1-gfx.obx 1.94 kB · 1 download Great. Note that my ZX02 variation should be much faster, and also the decoder is smaller. (138 bytes including initialization). Have Fun! 3 Quote Link to comment Share on other sites More sharing options...
xxl Posted July 21, 2022 Author Share Posted July 21, 2022 very good idea, zx1 could also be truncated to use 8-bit registers only Quote Link to comment Share on other sites More sharing options...
dmsc Posted July 21, 2022 Share Posted July 21, 2022 Hi! 2 hours ago, xxl said: very good idea, zx1 could also be truncated to use 8-bit registers only Yes, I could try over the weekend to see if there is any gain (in speed or code size) over ZX02. Have Fun! Quote Link to comment Share on other sites More sharing options...
xxl Posted July 21, 2022 Author Share Posted July 21, 2022 done: http://xxl.atari.pl/zx1-decompressor/ 1 Quote Link to comment Share on other sites More sharing options...
dmsc Posted July 22, 2022 Share Posted July 22, 2022 Hi! 12 hours ago, xxl said: very good idea, zx1 could also be truncated to use 8-bit registers only I made a new release that adds the ZX01 "based" compression format, download at: https://github.com/dmsc/zx02/releases/ For your "conan.gfx" file, those are the stats: Compressor Size ZX0 1625 ZX1 1671 ZX02 1629 ZX02 -1 1675 I wrote two decompressors in 6502, one "as small as possible", another "balanced", those are the sizes (bytes) and speeds (cycles/bytes): Format Type Size Speed ZX02 Small 130 72.6 ZX02 Optimized 138 58.0 ZX02 Fast 175 48.1 ZX02 -1 Small 131 56.0 ZX02 -1 Optimized 144 70.6 The sizes include all initialization, and the speed is measured in 6502 cycles, so lower number is faster. As you see, the ZX1 format does not make a big difference, and the decompressor sizes are bigger, so I'm not sure it is worth the effort. You can try to make the code smaller, those are the assembly sources: https://github.com/dmsc/zx02/blob/main/6502/zx102-optim.asm and https://github.com/dmsc/zx02/blob/main/6502/zx102-small.asm Have Fun! 5 Quote Link to comment Share on other sites More sharing options...
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