CSpect:known bugs

CSpect V2.12.5

• modifications to NextRegs done in copper propagate to rendering usually only once per scanline, usually retroactively for full scanline when triggered in h-blank area (palette changes, X/Y offsets, etc)
• copper write-index is not readable (NextReg $61, $62), and there is something wrong about writing beyond 1024 copper instructions (sometimes crashing whole emulator, sometimes just ruining the emulation results)
• copper execution doesn't wrap around
• many NextRegs are not readable until they are written into first (quick-boot mode without full NextZXOS image), trying to read some of them can crash the emulator
• Z80N bugs: ADD HL/DE/BC,A may affect carry flag, OUTI/OTIR does not decrement B before writing to I/O port, HALT doesn't stop execution under DI
• DMA: CONTINUE command is not implemented (will overwrite whole ZX memory), Zilog mode is not implemented
• blending modes: there's sometimes wrong half-pixel at end of paper area
• NextReg $69 doesn't read back correctly
• sprites: the collision bit is not implemented (intentionally for emulator performance reasons)
• sprites: mostly work except the "big sprites" having wrong compound transformations
• sprites rendering is not one-scanline-buffer delayed and all changes in sprites affect current scanline
• border color and Enhanced ULA on/off states sometimes produce incorrect results, sometimes the bottom area of border has different color
• blue color going through certain parts of rendering pipeline will get a notch brighter
• direct loading of NEX file doesn't init the machine in the same way as NEXLOAD from NextZXOS (memory filled by FF, etc)
• direct loading of NEX files does support only files without screen, or with Layer2+palette screen, every other type of file will crash the emulator
• 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)
• screen saver of NextZXOS will "crash" the emulated machine (not emulator itself)