Difference between revisions of "CSpect:known bugs"

Revision as of 22:39, 29 August 2021

CSpect V2.14.08

sprites: the collision bit is not implemented (intentional for performance reasons)
sprites rendering is not one-scanline-buffer delayed and all changes in sprites affect current scanline (intentional for performance reasons)
(IMPROVED in 2.14.08) modifications to NextRegs done in copper propagate to rendering usually only once per scanline, the state for rendering is sampled around end of right border area before h-blank area (palette changes, X/Y offsets, etc) (intentional for performance reasons)
modifications to NextRegs done by CPU propagate to rendering usually only once per scanline, usually retroactively for whole current scanline (mostly intentional for performance reasons)
FIXED: ~~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
DMA: reading-registers are a bit off (for example status bit5+0 not reset correctly after LOAD, probably few more (but core 3.1.5 also reads bit0 wrongly, so always test own code with all target platforms))
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
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 V2.14.08 (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) (should be improved since 2.14.01)
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)
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: something something about default clipping... just set clip windows explicitly in your SW.

Platform Specific

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

@@ Line 1: / Line 1: @@
 CSpect V2.14.08
-* sprites: the collision bit is not implemented (intentionally for emulator performance reasons)
+* sprites: the collision bit is not implemented (intentional for performance reasons)
-* sprites rendering is not one-scanline-buffer delayed and all changes in sprites affect current scanline (intentionally for emulator performance reasons)
+* sprites rendering is not one-scanline-buffer delayed and all changes in sprites affect current scanline (intentional for performance reasons)
-* (IMPROVED in 2.14.08) modifications to NextRegs done in copper propagate to rendering usually only once per scanline, the state for rendering is sampled around end of right border area before h-blank area (palette changes, X/Y offsets, etc) (mostly intentionally for emulator performance reasons)
+* (IMPROVED in 2.14.08) modifications to NextRegs done in copper propagate to rendering usually only once per scanline, the state for rendering is sampled around end of right border area before h-blank area (palette changes, X/Y offsets, etc) (intentional for 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)
+* modifications to NextRegs done by CPU propagate to rendering usually only once per scanline, usually retroactively for whole current scanline (mostly intentional for performance reasons)
 * FIXED: <del>missing Nextreg $64 "video line offset" (core 3.1.5)</del>
 * blending modes: the core 3.1.5 now blends Layer2+ULA in different way ([https://github.com/MrKWatkins/ZXSpectrumNextTests/issues/8 details]), CSpect renders it in the core2.0 - 3.0 way
@@ Line 17: / Line 17: @@
 * NextRegs $09, $34, $41, $8E read incorrectly (reads after certain writes produce wrong value)
-not verified in V2.14.03 (but known bugs of older versions, may be still present):
+not verified in V2.14.08 (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) (should be improved since 2.14.01)
 * 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)