byuu says:
Changelog: (all WSC unless otherwise noted)
- fixed LINECMP=0 interrupt case (fixes FF4 world map during airship
sequence)
- improved CPU timing (fixes Magical Drop flickering and FF1 battle
music)
- added per-frame OAM caching (fixes sprite glitchiness in Magical Drop,
Riviera, etc.)
- added RTC emulation (fixes Dicing Knight and Judgement Silversword)
- added save state support
- added cheat code support (untested because I don't know of any cheat
codes that exist for this system)
- icarus: can now detect games with RTC chips
- SFC: bugfix to SharpRTC emulation (Dai Kaijuu Monogatari II)
- ( I was adding the extra leap year day to all 12 months instead of
just February ... >_< )
Note that the RTC emulation is very incomplete. It's not really
documented at all, and the two games I've tried that use it never even
ask you to set the date/time (so they're probably just using it to count
seconds.) I'm not even sure if I've implement the level-sensitive
behavior correctly (actually, now that I think about it, I need to mask
the clear bit in INT_ACK for the level-sensitive interrupts ...)
A bit worried about the RTC alarm, because it seems like it'll fire
continuously for a full minute. Or even if you turn it off after it
fires, then that doesn't seem to be lowering the line until the next
second ticks on the RTC, so that likely needs to happen when changing
the alarm flag.
Also not sure on this RTC's weekday byte. On the SharpRTC, it actually
computes this for you. Because it's not at all an easy thing to
calculate yourself in 65816 or V30MZ assembler. About 40 lines of code
to do it in C. For now, I'm requiring the program to calculate the value
itself.
Also note that there's some gibberish tiles in Judgement Silversword,
sadly. Not sure what's up there, but the game's still fully playable at
least.
Finally, no surprise: Beat-Mania doesn't run :P
244 of 256 opcodes implemented now, although the interrupt triggering
portions are missing from them still. Much better handling of prefixes
now.
I definitely have a newfound hatepreciation for x86 now >_>
byuu says:
26 hours in, 173 instructions implemented. Although the four segment
prefix opcodes don't actually do anything yet. There's less than 256
actual instructions on the 80186, not sure of the exact count.
Gunpey gets around ~8,200 instructions in before hitting an unsupported
opcode (loop). Riviera goes off the rails on a retf and ends up
executing an endless stream of bad opcodes in RAM =( Both games hammer
the living shit out of the in/out ports pretty much immediately.
byuu says:
Man, the 80186 is taking a lot longer to implement than I thought it
would. So far I'm 18 hours into this emulator. Whereas I had Super Mario
Bros fully playable (no sound) in 12 hours for the NES >_>
I refactored all the byte/word variant functions to single functions
that take a size parameter. Cuts the amount of code in half.
Also implemented repz/repnz + movsb/movsw, so Riviera now gets 299
instructions in before dying. Nobody really bothers to explain how the
CPU actually implements these instructions, but I think I have it right:
ignore non-string opcodes that follow rep, invoke the string operations
inside the rep opcodes to prevent interrupts from triggering between the
two (which will be even more fun for segment selector overrides ...)
The next opcode needed is 0xC7, which ... throws ModRM on its head. In
this mode, ModRM is only used to determine the target operand (and it
doesn't use the middle bits for that at all), and the source is an
immediate that follows it. Gonna have to waste a few more hours thinking
about how best to handle that.
Also, disabled HiDPI for higan as well on OS X.
byuu says:
More V30MZ implemented, a lot more to go.
icarus now supports importing WS and WSC games. It expects them to have
the correct file extension, same for GB and GBC.
> Ugh, apparently HiDPI icarus doesn't let you press the check boxes.
I set the flag value in the plist to false for now. Forgot to do it for
higan, but hopefully I won't forget before release.
byuu says:
Lots of improvements. We're now able to start executing some V30MZ
instructions. 32 of 256 opcodes implemented so far.
I hope this goes without saying, but there's absolutely no point in
loading WS/WSC games right now. You won't see anything until I have the
full CPU and partial PPU implemented.
ROM bank 2 works properly now, the I/O map is 16-bit (address) x 16-bit
(data) as it should be*, and I have a basic disassembler in place
(adding to it as I emulate new opcodes.)
(* I don't know what happens if you access an 8-bit port in 16-bit mode
or vice versa, so for now I'm just treating the handlers as always being
16-bit, and discarding the upper 8-bits when not needed.)
Tim Allen