byuu says:
Changelog:
- processor/gsu: minor code cleanup
- processor/hg51b: renamed reg(Read,Write) to register(Read,Write)
- processor/lr35902: minor code cleanup
- processor/spc700: completed code cleanup (sans disassembler)
- no longer uses internal global state inside instructions
- processor/spc700: will no longer hang the emulator if stuck in a WAI
(SLEEP) or STP (STOP) instruction
- processor/spc700: fixed bug in handling of OR1 and AND1 instructions
- processor/z80: minor code cleanup
- sfc/dsp: revert to initializing registers to 0x00; save for
ENDX=random(), FLG=0xe0 [Jonas Quinn]
Major testing of the SNES game library would be appreciated, now that
its CPU cores have all been revised.
We know the DSP registers read back as randomized data ... mostly, but
there are apparently internal latches, which we can't emulate with the
current DSP design. So until we know which registers have separate
internal state that actually *is* initialized, I'm going to play it safe
and not break more games.
Thanks again to Jonas Quinn for the continued research into this issue.
EDIT: that said ... `MD works if((ENDX&0x30) > 0)` is only a 3:4 chance
that the game will work. That seems pretty unlikely that the odds of it
working are that low, given hardware testing by others in the past :/ I
thought if worked if `PITCH != 0` before, which would have been way more
likely.
The two remaining CPU cores that need major cleanup efforts are the
LR35902 and ARM cores. Both are very large, complicated, annoying cores
that will probably be better off as full rewrites from scratch. I don't
think I want to delay v103 in trying to accomplish that, however.
So I think it'll be best to focus on allowing the Mega Drive core to not
lock when processors are frozen waiting on a response from other
processors during a save state operation. Then we should be good for a
new release.
byuu says:
Changelog:
- md/ym2612: initialize DAC sample to center volume [Cydrak]
- processor/arm: add accumulate mode extra cycle to mlal [Jonas
Quinn]
- processor/huc6280: split off algorithms, improve naming of functions
- processor/mos6502: split off algorithms
- processor/spc700: major revamp of entire core (~50% completed)
- processor/wdc65816: fixed several bugs introduced by rewrite
For the SPC700, this turns out to be very old code as well, with global
object state variables, those annoying `{Boolean,Natural}BitField` types,
`under_case` naming conventions, heavily abbreviated function names, etc.
I'm working to get the code to be in the same design as the MOS6502,
HuC6280, WDC65816 cores, since they're all extremely similar in terms of
architectural design (the SPC700 is more of an off-label
reimplementation of a 6502 core, but still.)
The main thing left is that about 90% of the actual instructions still
need to be adapted to not use the internal state (`aa`, `rd`, `dp`,
`sp`, `bit` variables.) I wanted to finish this today, but ran out of
time before work.
I wouldn't suggest too much testing just yet. We should wait until the
SPC700 core is finished for that. However, if some does want to and
spots regressions, please let me know.
Tim Allen