CSpect:known bugs

CSpect V2.14.01

• sprites: the collision bit is not implemented (intentionally for emulator performance reasons)
• sprites rendering is not one-scanline-buffer delayed and all changes in sprites affect current/previous scanline (intentionally for emulator performance reasons)
• modifications to NextRegs done in copper propagate to rendering usually only once per scanline, usually retroactively for whole current scanline when triggered in h-blank area (palette changes, X/Y offsets, etc) (mostly intentionally for emulator performance reasons)
• modifications to NextRegs done by CPU propagate to rendering usually only once per scanline, usually retroactively for whole current scanline (mostly intentionally for emulator performance reasons)
• missing Nextreg $64 "video line offset" (core 3.1.5)
• blending modes: the core 3.1.5 now blends Layer2+ULA in different way (details), CSpect renders it in the core2.0 - 3.0 way
• sprites: 4bit relative patterns are incorrect in complex cases
• sprites: clipping is incorrect on Y2 in over-border mode, showing many pixels below the edge (other variants were not tested, so they may or may not be correct), and right side clip is now again incorrect
• DMA: reading-registers is a bit off (for example bit5+0 not reset correctly after LOAD, and probably more... contrary to core3.1.5 the bit0 is set)
• DMA: Zilog mode is not implemented (port 0x0B)
• NextReg $02 does not implement soft-reset (and probably also no hard-reset)
• sprites: the wrap-around the 512x512 coordinate space is only partially implemented in extreme cases (relative sprite so far from anchor that x8 scale wraps it back onto screen)
• border color and Enhanced ULA on/off states sometimes produce incorrect color of border and paper, and FLASH effect is not done by flipping pixel values
• default value: $6E and $6F are supposed to be fixed since V2.12.30, but the SNA test still reads zeroes
• some NextRegs read as zero until they are written into first (quick-boot mode with SNA file without full NextZXOS image) (for example regs $03, $12, $13, $14, $42, $4A, $4B, $4C)
• NextRegs $09, $34, $41, $8E read incorrectly (reads after certain writes produce wrong value)

not verified in V2.14.01 (but known bugs of older versions, may be still present):

• when running without the full NextZXOS card image, the esxdos services are provided by the emulator itself, the implementation is very limited and crude (most of the returned values are incorrect/etc, but loading files works)
• the initial file-import sequence of CP/M BIOS fails. (get cpm-a.p3d file from somebody with a working clean CP/M installation and copy that into c:/NextZXOS, or use other emulator to create the file)
• layers clipping - were +-1 or 2 pixel incorrect, but 2.12.37 fixed the ones I had in tests, need new test to verify all layers in all possible modes - .37 is probably mostly fixed
• blending modes: the new core3.1.3 blending (with extra Tiles|ULA front-slice) is not supported
• direct loading of NEX files does not support all combinations of loading-screen type and palette on/off (but V2.12.9 does load more files than V2.12.5, all common ones should work)
• sprites: the default clipping is wrong (set clip window explicitly any way) - this one was maybe silently fixed without changelog note, but I'm not sure (not interesting enough to run precise test)

Platform Specific

• Mac: Mouse does not work / behaves erratically
• Mac: after launch keyboard being irresponsive - try "alt+tab" to other app and back