Commit Graph

17 Commits

Author SHA1 Message Date
Tim Allen e9d2d56df9 Update to v105r1 release.
byuu says:

Changelog:

  - higan: readded support for soft-reset to Famicom, Super Famicom,
    Mega Drive cores (work in progress)
      - handhelds lack soft reset obviously
      - the PC Engine also lacks a physical reset button
      - the Master System's reset button acts like a gamepad button, so
        can't show up in the menu
  - Mega Drive: power cycle wasn't initializing CPU (M68K) or APU (Z80)
    RAM
  - Super Famicom: fix SPC700 opcode 0x3b regression; fixes Majuu Ou
    [Jonas Quinn]
  - Super Famicom: fix SharpRTC save regression; fixes Dai Kaijuu
    Monogatari II's real-time clock [Talarubi]
  - Super Famicom: fix EpsonRTC save regression; fixes Tengai Makyou
    Zero's real-time clock [Talarubi]
  - Super Famicom: removed `*::init()` functions, as they were never used
  - Super Famicom: removed all but two `*::load()` functions, as they
    were not used
  - higan: added option to auto-save backup RAM every five seconds
    (enabled by default)
      - this is in case the emulator crashes, or there's a power outage;
        turn it off under advanced settings if you want
  - libco: updated license from public domain to ISC, for consistency
    with nall, ruby, hiro
  - nall: Linux compiler defaults to g++; override with g++-version if
    g++ is <= 4.8
      - FreeBSD compiler default is going to remain g++49 until my dev
        box OS ships with g++ >= 4.9

Errata: I have weird RAM initialization constants, thanks to hex_usr
and onethirdxcubed for both finding this:
http://wiki.nesdev.com/w/index.php?title=CPU_power_up_state&diff=11711&oldid=11184

I'll remove this in the next WIP.
2017-11-07 09:05:54 +11:00
Tim Allen 3517d5c4a4 Update to v103r02 release.
byuu says:

Changelog:

  - fc/apu: improved phase duty cycle emulation (mode 3 is 25% phase
    inverted; counter decrements)
  - md/apu: power/reset do not cancel 68K bus requests
  - md/apu: 68K is not granted bus access on Z80 power/reset
  - md/controller: replaced System::Peripherals with ControllerPort
    concept
  - md/controller: CTRL port is now read-write, maintains value across
    controller changes (and soon, soft resets)
  - md/psg: PSG sampling rate unintentionally modified¹
  - processor/spc700: improve cycle timing of (indirect),y instructions
    [Overload]
  - processor/spc700: idle() cycles actually read from the program
    counter; much like the 6502 [Overload]
      - some of the idle() cycles should read from other addresses; this
        still needs to be supported
  - processor/spc700: various cleanups to instruction function naming
  - processor/z80: prefix state (HL→IX,IY override) can now be
    serialized
  - icarus: fix install rule for certain platforms (it wasn't buggy on
    FreeBSD, but was on Linux?)

¹: the clock speed of the PSG is oscillator/15. But I was setting the
sampling rate to oscillator/15/16, which was around 223KHz. I am not
sure whether the PSG should be outputting at 3MHz or 223KHz. Amazingly
... I don't really hear a difference either way `o_O` I didn't actually
mean to make this change; I just noticed it after comparing the diff
between r01 and r02. If this turns out to be wrong, set

    stream = Emulator::audio.createStream(1, frequency() / 16.0);

in md/psg.cpp to revert this change.
2017-06-27 11:18:28 +10:00
Tim Allen ecc7e899e0 Update to v103r01 release.
byuu says:

Changelog:

  - nall/dsp: improve one pole coefficient calculations [Fatbag]
  - higan/audio: reworked filters to support selection of either one
    pole (first-order) or biquad (second-order) filters
      - note: the design is not stable yet; so forks should not put too
        much effort into synchronizing with this change yet
  - fc: added first-order filters as per NESdev wiki (90hz lowpass +
    440hz lowpass + 14khz highpass)
  - fc: created separate NTSC-J and NTSC-U regions
      - NESdev wiki says the Japanese Famicom uses a separate audio
        filtering strategy, but details are fuzzy
      - there's also cartridge audio output being disabled on NES units;
        and differences with controllers
      - this stuff will be supported in the future, just adding the
        support for it now
  - gba: corrected serious bugs in PSG wave channel emulation [Cydrak]
      - note that if there are still bugs here, it's my fault
  - md/psg,ym2612: added first-order low-pass 2840hz filter to match
    VA3-VA6 Mega Drives
  - md/psg: lowered volume relative to the YM2612
      - using 0x1400; multiple people agreed it was the closest to the
        hardware recordings against a VA6
  - ms,md/psg: don't serialize the volume levels array
  - md/vdp: Hblank bit acts the same during Vblank as outside of it (it
    isn't always set during Vblank)
  - md/vdp: return isPAL in bit 0 of control port reads
  - tomoko: change command-line option separator from : to |
      - [Editor's note: This change was present in the public v103,
        but it's in this changelog because it was made after the v103 WIP]
  - higan/all: change the 20hz high-pass filters from second-order
    three-pass to first-order one-pass
      - these filters are meant to remove DC bias, but I honestly can't
        hear a difference with or without them
      - so there's really no sense wasting CPU power with an extremely
        powerful filter here

Things I did not do:

  - change icarus install rule
  - work on 8-bit Mega Drive SRAM
  - work on Famicom or Mega Drive region detection heuristics in icarus

My long-term dream plan is to devise a special user-configurable
filtering system where you can set relative volumes and create your own
list of filters (any number of them in any order at any frequency), that
way people can make the systems sound however they want.

Right now, the sanest place to put this information is inside the
$system.sys/manifest.bml files. But that's not very user friendly, and
upgrading to new versions will lose these changes if you don't copy them
over manually. Of course, cluttering the GUI with a fancy filter editor
is probably supreme overkill for 99% of users, so maybe that's fine.
2017-06-26 11:41:58 +10:00
Tim Allen 50411a17d1 Update to v102r26 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.
2017-06-16 10:06:17 +10:00
Tim Allen 82c58527c3 Update to v102r17 release.
byuu says:

Changelog:

  - GBA: process audio at 2MHz instead of 32KHz¹
  - MD: do not allow the 68K to stop the Z80, unless it has been granted
    bus access first
  - MD: do not reset bus requested/granted signals when the 68K resets
    the Z80
      - the above two fix The Lost Vikings
  - MD: clean up the bus address decoding to be more readable
  - MD: add support for a13000-a130ff (#TIME) region; pass to cartridge
    I/O²
  - MD: emulate SRAM mapping used by >16mbit games; bank mapping used
    by >32mbit games³
  - MD: add 'reset pending' flag so that loading save states won't
    reload 68K PC, SP registers
      - this fixes save state support ... mostly⁴
  - MD: if DMA is not enabled, do not allow CD5 to be set [Cydrak]
      - this fixes in-game graphics for Ristar. Title screen still
        corrupted on first run
  - MD: detect and break sprite lists that form an infinite loop
    [Cydrak]
      - this fixes the emulator from dead-locking on certain games
  - MD: add DC offset to sign DAC PCM samples [Cydrak]
      - this improves audio in Sonic 3
  - MD: 68K TAS has a hardware bug that prevents writing the result back
    to RAM
      - this fixes Gargoyles
  - MD: 68K TRAP should not change CPU interrupt level
      - this fixes Shining Force II, Shining in the Darkness, etc
  - icarus: better SRAM heuristics for Mega Drive games

Todo:

  - need to serialize the new cartridge ramEnable, ramWritable, bank
    variables

¹: so technically, the GBA has its FIFO queue (raw PCM), plus a GB
chipset. The GB audio runs at 2MHz. However, I was being lazy and
running the sequencer 64 times in a row, thus decimating the audio to
32KHz. But simply discarding 63 out of every 64 samples resorts in
muddier sound with more static in it.

However ... increasing the audio thread processing intensity 64-fold,
and requiring heavy-duty three-chain lowpass and highpass filters is not
cheap. For this bump in sound quality, we're eating a loss of about 30%
of previous performance.

Also note that the GB audio emulation in the GBA core still lacks many
of the improvements made to the GB core. I was hoping to complete the GB
enhancements, but it seems like I'm never going to pass blargg's
psychotic edge case tests. So, first I want to clean up the GB audio to
my current coding standards, and then I'll port that over to the GBA,
which should further increase sound quality. At that point, it sound
exceed mGBA's audio quality (due to the ridiculously high sampling rate
and strong-attenuation audio filtering.)

²: word writes are probably not handled correctly ... but games are
only supposed to do byte writes here.

³: the SRAM mapping is used by games like "Story of Thor" and
"Phantasy Star IV." Unfortunately, the former wasn't released in the US
and is region protected. So you'll need to change the NTSU to NTSCJ in
md/system/system.cpp in order to boot it. But it does work nicely now.
The write protection bit is cleared in the game, and then it fails to
write to SRAM (soooooooo many games with SRAM write protection do this),
so for now I've had to disable checking that bit. Phantasy Star IV has a
US release, but sadly the game doesn't boot yet. Hitting some other bug.

The bank mapping is pretty much just for the 40mbit Super Street Fighter
game. It shows the Sega and Capcom logos now, but is hitting yet another
bug and deadlocking.

For now, I emulate the SRAM/bank mapping registers on all cartridges,
and set sane defaults. So long as games don't write to $a130XX, they
should all continue to work. But obviously, we need to get to a point
where higan/icarus can selectively enable these registers on a per-game
basis.

⁴: so, the Mega Drive has various ways to lock a chip until another
chip releases it. The VDP can lock the 68K, the 68K can lock the Z80,
etc. If this happens when you save a state, it'll dead-lock the
emulator. So that's obviously a problem that needs to be fixed. The fix
will be nasty ... basically, bypassing the dead-lock, creating a
miniature, one-instruction-long race condition. Extremely unlikely to
cause any issues in practice (it's only a little worse than the SNES
CPU/SMP desync), but ... there's nothing I can do about it. So you'll
have to take it or leave it. But yeah, for now, save states may lock up
the emulator. I need to add code to break the loops when in the process
of creating a save state still.
2017-03-10 21:23:29 +11:00
Tim Allen 04072b278b Update to v102r16 release.
byuu says:

Changelog:

  - Emulator::Stream now allows adding low-pass and high-pass filters
    dynamically
      - also accepts a pass# count; each pass is a second-order biquad
        butterworth IIR filter
  - Emulator::Stream no longer automatically filters out >20KHz
    frequencies for all streams
  - FC: added 20Hz high-pass filter; 20KHz low-pass filter
  - GB: removed simple 'magic constant' high-pass filter of unknown
    cutoff frequency (missed this one in the last WIP)
  - GB,SGB,GBC: added 20Hz high-pass filter; 20KHz low-pass filter
  - MS,GG,MD/PSG: added 20Hz high-pass filter; 20KHz low-pass filter
  - MD: added save state support (but it's completely broken for now;
    sorry)
  - MD/YM2612: fixed Voice#3 per-operator pitch support (fixes sound
    effects in Streets of Rage, etc)
  - PCE: added 20Hz high-pass filter; 20KHz low-pass filter
  - WS,WSC: added 20Hz high-pass filter; 20KHz low-pass filter

So, the point of the low-pass filters is to remove frequencies above
human hearing. If we don't do this, then resampling will introduce
aliasing that results in sounds that are audible to the human ear. Which
basically an annoying buzzing sound. You'll definitely hear the
improvement from these in games like Mega Man 2 on the NES. Of course,
these already existed before, so this WIP won't sound better than
previous WIPs.

The high-pass filters are a little more complicated. Their main role is
to remove DC bias and help to center the audio stream. I don't
understand how they do this at all, but ... that's what everyone who
knows what they're talking about says, thus ... so be it.

I have set all of the high-pass filters to 20Hz, which is below the
limit of human hearing. Now this is where it gets really interesting ...
technically, some of these systems actually cut off a lot of range. For
instance, the GBA should technically use an 800Hz high-pass filter when
output is done through the system's speakers. But of course, if you plug
in headphones, you can hear the lower frequencies.

Now 800Hz ... you definitely can hear. At that level, nearly all of the
bass is stripped out and the audio is very tinny. Just like the real
system. But for now, I don't want to emulate the audio being crushed
that badly.

I'm sticking with 20Hz everywhere since it won't negatively affect audio
quality. In fact, you should not be able to hear any difference between
this WIP and the previous WIP. But theoretically, DC bias should mostly
be removed as a result of these new filters. It may be that we need to
raise the values on some cores in the future, but I don't want to do
that until we know for certain that we have to.

What I can say is that compared to even older WIPs than r15 ... the
removal of the simple one-pole low-pass and high-pass filters with the
newer three-pass, second-order filters should result in much better
attenuation (less distortion of audible frequencies.) Probably not
enough to be noticeable in a blind test, though.
2017-03-09 07:20:40 +11:00
Tim Allen 7e7003fd29 Update to v102r15 release.
byuu says:

Changelog:

  - nall: added DSP::IIR::OnePole (which is a first-order IIR filter)
  - FC/APU: removed strong highpass, weak hipass filters (and the
    dummied out lowpass filter)
  - MS,GG,MD/PSG: removed lowpass filter
  - MS,GG,MD/PSG: audio was not being centered properly; removed
    centering for now
  - MD/YM2612: fixed clipping of accumulator from 18 signed bits to 14
    signed bits (-0x2000 to +0x1fff) [Cydrak]
  - MD/YM2612: removed lowpass filter
  - PCE/PSG: audio was not being centered properly; removed centering
    for now

First thing is that I've removed all of the ad-hoc audio filtering.
Emulator::Stream intrinsically provides a three-pass, second-order
biquad IIR butterworth lowpass filter that clips frequencies above 20KHz
with very good attenuation (as good as IIR gets, anyway.)

It doesn't really make sense to have the various cores running
additional lowpass filters. If we want to filter frequencies below
20KHz, then I can adapt Emulator::Audio::createStream() to take a cutoff
frequency value, and we can do it all at once, with much better quality.

Right now, I don't know what frequencies are best to cut off the various
other audio cores, so they're just gone for now.

As for the highpass filters for the Famicom core, well ... you don't get
aliasing from resampling low frequencies. And generally speaking, too
low a frequency will be inaudible anyway. All these were doing was
killing possible bass (if they were too strong.) We can add them again,
but only if someone can convert Ryphecha's ad-hoc magic integers into a
frequency cutoff. In which case, I'll use my biquad IIR filter to do it
even better. On this note, it may prove useful to do this for the MD PSG
as well, to try and head off unnecessary clamping when mixing with the
YM2612.

Finally, there was the audio centering issue that affected the
MS,GG,MD,PCE,SG cores. It was flooring the "silent" audio level, which
was resulting in extremely heavy distortion if you tried listening to
higan and, say, audacious at the same time. Without the botched
centering, this distortion is completely gone now.

However, without any centering, we've halved the potential volume range.
This means the audio slider in higan's audio settings panel will start
clamping twice as quickly. So ultimately, we need to figure out how to
fix the centering. This isn't as simple as just subtracting less. We
will probably have to center every individual audio channel before
summing them to do this properly.

Results:

On the Mega Drive, Altered Beast sounds quite a bit better, a lot less
distortion now. But it's still not perfect, especially sound effects.
Further, Bare Knuckle / Streets of Rage still has really bad sound
effects. It looks like I broke something in Cydrak's code when trying to
adapt it to my style =(
2017-03-07 07:23:22 +11:00
Tim Allen 89d47914b9 Update to v102r14 release.
byuu says:

Changelog:

  - (MS,GG,MD)/PSG: flip output bit from noise channel [TmEE]
  - MD/YM2612: rewrite YM2612::Channel functions to
    YM2612::Channel::Operator functions¹
  - MD/YM2612: pitch/octave I/O registers should set reload, not value
    (fixes sound in most games)
  - MD/YM2612: don't try to sign-extend raw PCM values (fixes Shining
    Force opening music)
  - MD/YM2612: various algorithm simplifications; conversions from
    `*`, `/`, `%` to `<<`, `>>`; etc.

Overall ... Sonic the Hedgehog sounds really, really great. Almost
perfect, but there's a bit of clamping going on in the special zones.
Langrisser II sounds really great. Shining Force sounds pretty much
perfect. Bare Knucles (Streets of Rage) does pretty badly ... punches
sound more like dinging a salad fork on a wine glass, heh. Altered Beast
is extremely broken ... no music at the title screen, very distorted
in-game music. I suspect a bug outside of the YM2612 is affecting this
game.

So, the YM2612 emulation isn't perfect, but it's a really good start to
the most complex sound chip in all of higan. Hopefully the VRC7 and
YM2413 will prove to be less ferocious ... not that I'm in any rush to
work on either. The former is going to need the NES mapper rewrite to be
done first, and the latter is cool but not very necessary since all
those games have fallbacks to the inferior PSG audio.

But really ... I can't thank Cydrak enough for doing this for me. It
would have probably taken me months to parse through all of the
documentation on this chip (most of which is in a 55-page thread on
spritesmind that is filled with wrong/outdated information at the start,
and corrections as you go deeper.) Not to mention, learning about what
the hell detuning, low-frequency oscillation, tremolo, vibrato, etc were
all about. Or how those algorithms to compute the final output work. Or
the dozens of special cases littered in there to make everything sound
good. Fierce, nasty chip that.

Now the last real problem is save states ... the Mega Drive is going to
be the trickiest of all to implement with libco. There are lots of areas
where one chip will deadlock another chip while it completes some
operation. We don't have a choice but to force those stalls to abort
anyway, in order to let libco reach the start of its entry point once
again. I don't know what kind of impact that'll have on states ... I
suspect they'll work almost as reliably as the SNES does, but I can't
know that until I implement it. It's going to be pretty nasty, though.

¹: this basically removes a lot of unnecessary op. prefixes and the
need to capture `auto& op = operators[index]` at the start of every
function.

I wanted to have subfunctions like
`YM2612::Channel::Operator::Envelope::run()`, etc but unfortunately,
pretty much all of the envelope, phase, pitch, level functions need to
access each other's state.
2017-03-03 21:45:07 +11:00
Tim Allen 0bf2c9d4e1 Update to v102r13 release.
byuu says:

Changelog:

  - removed Emulator::Interface::videoFrequency(), audioFrequency()¹
  - (MS,GG,MD)/PSG: removed inversion on noise channel LFSR update
    [mic_]
  - MD/PSG: lowered volume to match YM2612 volume
  - MD/YM2612: added Cydrak's emulation of FM channels and LFO²

¹: These were no longer used by the UI. The video frequency is
adaptive on many systems. And the audio frequency is meaningless due to
Emulator::Audio always outputting a consistent frequency specified by
the UI. Plus, take the Genesis where there's two sound chips running at
different frequencies. So, these had to go.

²: Due to some lurking bugs, the audio is completely broken
unfortunately. Will need to be debugged :(

First pass looking for any typos didn't yield any obvious results.
2017-03-02 07:40:55 +11:00
Tim Allen 4c3f9b93e7 Update to v102r12 release.
byuu says:

Changelog:

  - MD/PSG: fixed 68K bus Z80 status read address location
  - MS, GG, MD/PSG: channels post-decrement their counters, not
    pre-decrement [Cydrak]¹
  - MD/VDP: cache screen width registers once per scanline; screen
    height registers once per frame
  - MD/VDP: support 256-width display mode (used in Shining Force, etc)
  - MD/YM2612: implemented timers²
  - MD/YM2612: implemented 8-bit PCM DAC²
  - 68000: TRAP instruction should index the vector location by 32 (eg
    by 128 bytes), fixes Shining Force
  - nall: updated hex(), octal(), binary() functions to take uintmax
    instead of template<typename T> parameter³

¹: this one makes an incredible difference. Sie noticed that lots of
games set a period of 0, which would end up being a really long period
with pre-decrement. By fixing this, noise shows up in many more games,
and sounds way better in games even where it did before. You can hear
extra sound on Lunar - Sanposuru Gakuen's title screen, the noise in
Sonic The Hedgehog (Mega Drive) sounds better, etc.

²: this also really helps sound. The timers allow PSG music to play
back at the correct speed instead of playing back way too quickly. And
the PCM DAC lets you hear a lot of drum effects, as well as the
"Sega!!" sound at the start of Sonic the Hedgehog, and the infamous,
"Rise from your grave!" line from Altered Beast.

Still, most music on the Mega Drive comes from the FM channels, so
there's still not a whole lot to listen to.

I didn't implement Cydrak's $02c test register just yet. Sie wasn't 100%
certain on how the extended DAC bit worked, so I'd like to play it a
little conservative and get sound working, then I'll go back and add a
toggle or something to enable undocumented registers, that way we can
use that to detect any potential problems they might be causing.

³: unfortunately we lose support for using hex() on nall/arithmetic
types. If I have a const Pair& version of the function, then the
compiler gets confused on whether Natural<32> should use uintmax or
const Pair&, because compilers are stupid, and you can't have explicit
arguments in overloaded functions. So even though either function would
work, it just decides to error out instead >_>

This is actually really annoying, because I want hex() to be useful for
printing out nall/crypto keys and hashes directly.

But ... this change had to be made. Negative signed integers would crash
programs, and that was taking out my 68000 disassembler.
2017-02-27 19:45:51 +11:00
Tim Allen 68f04c3bb8 Update to v102r10 release.
byuu says:

Changelog:

  - removed Emulator::Interface::Capabilities¹
  - MS: improved the PSG emulation a bit
  - MS: added cheat code support
  - MS: added save state support²
  - MD: emulated the PSG³

¹: there's really no point to it anymore. I intend to add cheat codes
to the GBA core, as well as both cheat codes and save states to the Mega
Drive core. I no longer intend to emulate any new systems, so these
values will always be true. Further, the GUI doesn't respond to these
values to disable those features anymore ever since the hiro rewrite, so
they're double useless.

²: right now, the Z80 core is using a pointer for HL-\>(IX,IY)
overrides. But I can't reliably serialize pointers, so I need to convert
the Z80 core to use an integer here. The save states still appear to
work fine, but there's the potential for an instruction to execute
incorrectly if you're incredibly unlucky, so this needs to be fixed as
soon as possible. Further, I still need a way to serialize
array<T, Size> objects, and I should also add nall::Boolean
serialization support.

³: I don't have a system in place to share identical sound chips. But
this chip is so incredibly simple that it's not really much trouble to
duplicate it. Further, I can strip out the stereo sound support code
from the Game Gear portion, so it's even tinier.

Note that the Mega Drive only just barely uses the PSG. Not at all in
Altered Beast, and only for a tiny part of the BGM music on Sonic 1,
plus his jump sound effect.
2017-02-23 08:25:01 +11:00
Tim Allen d76c0c7e82 Update to v102r08 release.
byuu says:

Changelog:

  - PCE: restructured VCE, VDCs to run one scanline at a time
  - PCE: bound VDCs to 1365x262 timing (in order to decouple the VDCs
    from the VCE)
  - PCE: the two changes above allow save states to function; also
    grants a minor speed boost
  - PCE: added cheat code support (uses 21-bit bus addressing; compare
    byte will be useful here)
  - 68K: fixed `mov *,ccr` to read two bytes instead of one [Cydrak]
  - Z80: emulated /BUSREQ, /BUSACK; allows 68K to suspend the Z80
    [Cydrak]
  - MD: emulated the Z80 executing instructions [Cydrak]
  - MD: emulated Z80 interrupts (triggered during each Vblank period)
    [Cydrak]
  - MD: emulated Z80 memory map [Cydrak]
  - MD: added stubs for PSG, YM2612 accesses [Cydrak]
  - MD: improved bus emulation [Cydrak]

The PCE core is pretty much ready to go. The only major feature missing
is FM modulation.

The Mega Drive improvements let us start to see the splash screens for
Langrisser II, Shining Force, Shining in the Darkness. I was hoping I
could get them in-game, but no such luck. My Z80 implementation is
probably flawed in some way ... now that I think about it, I believe I
missed the BusAPU::reset() check for having been granted access to the
Z80 first. But I doubt that's the problem.

Next step is to implement Cydrak's PSG core into the Master System
emulator. Once that's in, I'm going to add save states and cheat code
support to the Master System core.

Next, I'll add the PSG core into the Mega Drive. Then I'll add the
'easy' PCM part of the YM2612. Then the rest of the beastly YM2612 core.
Then finally, cap things off with save state and cheat code support.

Should be nearing a new release at that point.
2017-02-20 19:13:10 +11:00
Tim Allen bdc100e123 Update to v102r02 release.
byuu says:

Changelog:

  - I caved on the `samples[] = {0.0}` thing, but I'm very unhappy about it
      - if it's really invalid C++, then GCC needs to stop accepting it
        in strict `-std=c++14` mode
  - Emulator::Interface::Information::resettable is gone
  - Emulator::Interface::reset() is gone
  - FC, SFC, MD cores updated to remove soft reset behavior
  - split GameBoy::Interface into GameBoyInterface,
    GameBoyColorInterface
  - split WonderSwan::Interface into WonderSwanInterface,
    WonderSwanColorInterface
  - PCE: fixed off-by-one scanline error [hex_usr]
  - PCE: temporary hack to prevent crashing when VDS is set to < 2
  - hiro: Cocoa: removed (u)int(#) constants; converted (u)int(#)
    types to (u)int_(#)t types
  - icarus: replaced usage of unique with strip instead (so we don't
    mess up frameworks on macOS)
  - libco: added macOS-specific section marker [Ryphecha]

So ... the major news this time is the removal of the soft reset
behavior. This is a major!! change that results in a 100KiB diff file,
and it's very prone to accidental mistakes!! If anyone is up for
testing, or even better -- looking over the code changes between v102r01
and v102r02 and looking for any issues, please do so. Ideally we'll want
to test every NES mapper type and every SNES coprocessor type by loading
said games and power cycling to make sure the games are all cleanly
resetting. It's too big of a change for me to cover there not being any
issues on my own, but this is truly critical code, so yeah ... please
help if you can.

We technically lose a bit of hardware documentation here. The soft reset
events do all kinds of interesting things in all kinds of different
chips -- or at least they do on the SNES. This is obviously not ideal.
But in the process of removing these portions of code, I found a few
mistakes I had made previously. It simplifies resetting the system state
a lot when not trying to have all the power() functions call the reset()
functions to share partial functionality.

In the future, the goal will be to come up with a way to add back in the
soft reset behavior via keyboard binding as with the Master System core.
What's going to have to happen is that the key binding will have to send
a "reset pulse" to every emulated chip, and those chips are going to
have to act independently to power() instead of reusing functionality.
We'll get there eventually, but there's many things of vastly greater
importance to work on right now, so it'll be a while. The information
isn't lost ... we'll just have to pull it out of v102 when we are ready.

Note that I left the SNES reset vector simulation code in, even though
it's not possible to trigger, for the time being.

Also ... the Super Game Boy core is still disconnected. To be honest, it
totally slipped my mind when I released v102 that it wasn't connected
again yet. This one's going to be pretty tricky to be honest. I'm
thinking about making a third GameBoy::Interface class just for SGB, and
coming up with some way of bypassing platform-> calls when in this
mode.
2017-01-23 08:04:26 +11:00
Tim Allen 1df2549d18 Update to v101r04 release.
byuu says:

Changelog:

  - pulled the (u)intN type aliases into higan instead of leaving them
    in nall
  - added 68K LINEA, LINEF hooks for illegal instructions
  - filled the rest of the 68K lambda table with generic instance of
    ILLEGAL
  - completed the 68K disassembler effective addressing modes
      - still unsure whether I should use An to decode absolute
        addresses or not
      - pro: way easier to read where accesses are taking place
      - con: requires An to be valid; so as a disassembler it does a
        poor job
      - making it optional: too much work; ick
  - added I/O decoding for the VDP command-port registers
  - added skeleton timing to all five processor cores
  - output at 1280x480 (needed for mixed 256/320 widths; and to handle
    interlace modes)

The VDP, PSG, Z80, YM2612 are all stepping one clock at a time and
syncing; which is the pathological worst case for libco. But they also
have no logic inside of them. With all the above, I'm averaging around
250fps with just the 68K core actually functional, and the VDP doing a
dumb "draw white pixels" loop. Still way too early to tell how this
emulator is going to perform.

Also, the 320x240 mode of the Genesis means that we don't need an aspect
correction ratio. But we do need to ensure the output window is a
multiple 320x240 so that the scale values work correctly. I was
hard-coding aspect correction to stretch the window an additional \*8/7.
But that won't work anymore so ... the main higan window is now 640x480,
960x720, or 1280x960. Toggling aspect correction only changes the video
width inside the window.

It's a bit jarring ... the window is a lot wider, more black space now
for most modes. But for now, it is what it is.
2016-08-12 11:07:04 +10:00
Tim Allen ca277cd5e8 Update to v100r14 release.
byuu says:

(Windows: compile with -fpermissive to silence an annoying error. I'll
fix it in the next WIP.)

I completely replaced the time management system in higan and overhauled
the scheduler.

Before, processor threads would have "int64 clock"; and there would
be a 1:1 relationship between two threads. When thread A ran for X
cycles, it'd subtract X * B.Frequency from clock; and when thread B ran
for Y cycles, it'd add Y * A.Frequency from clock. This worked well
and allowed perfect precision; but it doesn't work when you have more
complicated relationships: eg the 68K can sync to the Z80 and PSG; the
Z80 to the 68K and PSG; so the PSG needs two counters.

The new system instead uses a "uint64 clock" variable that represents
time in attoseconds. Every time the scheduler exits, it subtracts
the smallest clock count from all threads, to prevent an overflow
scenario. The only real downside is that rounding errors mean that
roughly every 20 minutes, we have a rounding error of one clock cycle
(one 20,000,000th of a second.) However, this only applies to systems
with multiple oscillators, like the SNES. And when you're in that
situation ... there's no such thing as a perfect oscillator anyway. A
real SNES will be thousands of times less out of spec than 1hz per 20
minutes.

The advantages are pretty immense. First, we obviously can now support
more complex relationships between threads. Second, we can build a
much more abstracted scheduler. All of libco is now abstracted away
completely, which may permit a state-machine / coroutine version of
Thread in the future. We've basically gone from this:

    auto SMP::step(uint clocks) -> void {
      clock += clocks * (uint64)cpu.frequency;
      dsp.clock -= clocks;
      if(dsp.clock < 0 && !scheduler.synchronizing()) co_switch(dsp.thread);
      if(clock >= 0 && !scheduler.synchronizing()) co_switch(cpu.thread);
    }

To this:

    auto SMP::step(uint clocks) -> void {
      Thread::step(clocks);
      synchronize(dsp);
      synchronize(cpu);
    }

As you can see, we don't have to do multiple clock adjustments anymore.
This is a huge win for the SNES CPU that had to update the SMP, DSP, all
peripherals and all coprocessors. Likewise, we don't have to synchronize
all coprocessors when one runs, now we can just synchronize the active
one to the CPU.

Third, when changing the frequencies of threads (think SGB speed setting
modes, GBC double-speed mode, etc), it no longer causes the "int64
clock" value to be erroneous.

Fourth, this results in a fairly decent speedup, mostly across the
board. Aside from the GBA being mostly a wash (for unknown reasons),
it's about an 8% - 12% speedup in every other emulation core.

Now, all of this said ... this was an unbelievably massive change, so
... you know what that means >_> If anyone can help test all types of
SNES coprocessors, and some other system games, it'd be appreciated.

----

Lastly, we have a bitchin' new about screen. It unfortunately adds
~200KiB onto the binary size, because the PNG->C++ header file
transformation doesn't compress very well, and I want to keep the
original resource files in with the higan archive. I might try some
things to work around this file size increase in the future, but for now
... yeah, slightly larger archive sizes, sorry.

The logo's a bit busted on Windows (the Label control's background
transparency and alignment settings aren't working), but works well on
GTK. I'll have to fix Windows before the next official release. For now,
look on my Twitter feed if you want to see what it's supposed to look
like.

----

EDIT: forgot about ICD2::Enter. It's doing some weird inverse
run-to-save thing that I need to implement support for somehow. So, save
states on the SGB core probably won't work with this WIP.
2016-07-30 13:56:12 +10:00
Tim Allen 76a8ecd32a Update to v100r03 release.
byuu says:

Changelog:
- moved Thread, Scheduler, Cheat functionality into emulator/ for
  all cores
- start of actual Mega Drive emulation (two 68K instructions)

I'm going to be rather terse on MD emulation, as it's too early for any
meaningful dialogue here.
2016-07-10 15:28:26 +10:00
Tim Allen 3dd1aa9c1b Update to v100r02 release.
byuu says:

Sigh ... I'm really not a good person. I'm inherently selfish.

My responsibility and obligation right now is to work on loki, and
then on the Tengai Makyou Zero translation, and then on improving the
Famicom emulation.

And yet ... it's not what I really want to do. That shouldn't matter;
I should work on my responsibilities first.

Instead, I'm going to be a greedy, self-centered asshole, and work on
what I really want to instead.

I'm really sorry, guys. I'm sure this will make a few people happy,
and probably upset even more people.

I'm also making zero guarantees that this ever gets finished. As always,
I wish I could keep these things secret, so if I fail / give up, I could
just drop it with no shame. But I would have to cut everyone out of the
WIP process completely to make it happen. So, here goes ...

This WIP adds the initial skeleton for Sega Mega Drive / Genesis
emulation. God help us.

(minor note: apparently the new extension for Mega Drive games is .md,
neat. That's what I chose for the folders too. I thought it was .smd,
so that'll be fixed in icarus for the next WIP.)

(aside: this is why I wanted to get v100 out. I didn't want this code in
a skeleton state in v100's source. Nor did I want really broken emulation,
which the first release is sure to be, tarring said release.)

...

So, basically, I've been ruminating on the legacy I want to leave behind
with higan. 3D systems are just plain out. I'm never going to support
them. They're too complex for my abilities, and they would run too slowly
with my design style. I'm not willing to compromise my design ideals. And
I would never want to play a 3D game system at native 240p/480i resolution
... but 1080p+ upscaling is not accurate, so that's a conflict I want
to avoid entirely. It's also never going to emulate computer systems
(X68K, PC-98, FM-Towns, etc) because holy shit that would completely
destroy me. It's also never going emulate arcade machines.

So I think of higan as a collection of 2D emulators for consoles
and handhelds. I've gone over every major 2D gaming system there is,
looking for ones with games I actually care about and enjoy. And I
basically have five of those systems supported already. Looking at the
remaining list, I see only three systems left that I have any interest
in whatsoever: PC-Engine, Master System, Mega Drive. Again, I'm not in
any way committing to emulating any of these, but ... if I had all of
those in higan, I think I'd be content to really, truly, finally stop
writing more emulators for the rest of my life.

And so I decided to tackle the most difficult system first. If I'm
successful, the Z80 core should cover a lot of the work on the SMS. And
the HuC6280 should land somewhere between the NES and SNES in terms of
difficulty ... closer to the NES.

The systems that just don't appeal to me at all, which I will never touch,
include, but are not limited to:
* Atari 2600/5200/7800
* Lynx
* Jaguar
* Vectrex
* Colecovision
* Commodore 64
* Neo-Geo
* Neo-Geo Pocket / Color
* Virtual Boy
* Super A'can
* 32X
* CD-i
* etc, etc, etc.

And really, even if something were mildly interesting in there ... we
have to stop. I can't scale infinitely. I'm already way past my limit,
but I'm doing this anyway. Too many cores bloats everything and kills
quality on everything. I don't want higan to become MESS v2.

I don't know what I'll do about the Famicom Disk System, PC-Engine CD,
and Mega CD. I don't think I'll be able to achieve 60fps emulating the
Mega CD, even if I tried to.

I don't know what's going to happen here with even the Mega Drive. Maybe
I'll get driven crazy with the documentation and quit. Maybe it'll end
up being too complicated and I'll quit. Maybe the emulation will end up
way too slow and I'll give up. Maybe it'll take me seven years to get
any games playable at all. Maybe Steve Snake, AamirM and Mike Pavone
will pool money to hire a hitman to come after me. Who knows.

But this is what I want to do, so ... here goes nothing.
2016-07-09 14:21:37 +10:00