ZEsarUX:known bugs
From SpecNext official Wiki
Official ZEsarUX 8.1:
- sprites rendering is at "4B type" level (no anchor/relative sprites or scaling) (5B init is correctly accepted but doesn't render the extra features)
- 4bpp sprites are not supported
- sprites rendering is not one-scanline-buffer delayed and all changes in sprites affect current scanline
- Layer 2 displays shadow variant (NextReg $13) when the "shadow" mapping is enabled
- 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)
- palette read (NextReg $41 + $44 produces wrong results)
- tilemode gfx/map address read (NextReg $6E + $6F) does return original value without top bits set to zero
- DMA: too many differences to list, but most crucial: CONTINUE is not supported, slow "burst" functionality is not complete, legacy Z80 mode is not implemented
- blending modes are not implemented
- ULA scroll is not at new NextReg $26, $27 (but still shared with LoRes offset registers)
- audio has "clicks" and noise on many platforms, although YMMV
- 28MHz mode requires quite powerful PC to emulate it smoothly, "lagging" emulator menu/etc is likely to happen in 28MHz mode.
- monochrome tilemode has not fully correct colours handling
- direct loading of NEX file doesn't init the machine in the same way as NEXLOAD from NextZXOS (it's close, but few things are different)
- screen saver of NextZXOS will "crash" the emulated machine (not emulator itself)
Personal "ZESERUse" fork of Ped7g:
- 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) - when compiled with extra flag "-DTBBLUE_DELAYED_COPPER_WAITS" it will delay copper instructions waiting for h-blank till next line (does produce better visual output in some cases, but makes the emulation less accurate in terms of timing)
- altROM/global memory map not updated to core 3.1.0 changes
- audio has "clicks" and noise on many platforms, although YMMV
- 28MHz mode requires quite powerful PC to emulate it smoothly, "lagging" emulator menu/etc is likely to happen in 28MHz mode - the fork is even more power hungry than official version
- blending modes are temporarily not working (implemented in older versions, but broken in latest)
- sprites rendering is not one-scanline-buffer delayed and all changes in sprites affect current scanline, calculation of pixel-bandwidth exhaustion is vastly incorrect
- screen saver of NextZXOS will "crash" the emulated machine (not emulator itself)