Commit Graph

575 Commits

Author SHA1 Message Date
Tim Allen a4629e1f64 Update to v102r21 release.
byuu says:

Changelog:

  - GBA: fixed WININ2 reads, BG3PB writes [Jonas Quinn]
  - R65816: added support for yielding/resuming from WAI/STP¹
  - SFC: removed status.dmaCounter functionality (also fixes possible
    TAS desync issue)
  - tomoko: added support for combinatorial inputs [hex\_usr\]²
  - nall: fixed missing return value from Arithmetic::operator--
    [Hendricks266]

Now would be the time to start looking for major regressions with the
new GBA PPU renderer, I suppose ...

¹: this doesn't matter for the master thread (SNES CPU), but is
important for slave threads (SNES SA1). If you try to save a state and
the SA1 is inside of a WAI instruction, it will get stuck there forever.
This was causing attempts to create a save state in Super Bomberman
- Panic Bomber W to deadlock the emulator and crash it. This is now
finally fixed.

Note that I still need to implement similar functionality into the Mega
Drive 68K and Z80 cores. They still have the possibility of deadlocking.
The SNES implementation was more a dry-run test for this new
functionality. This possible crashing bug in the Mega Drive core is the
major blocking bug for a new official release.

²: many, many thanks to hex\_usr for coming up with a really nice
design. I mostly implemented it the exact same way, but with a few tiny
differences that don't really matter (display " and ", " or " instead of
" & ", " | " in the input settings windows; append → bind;
assignmentName changed to displayName.)

The actual functionality is identical to the old higan v094 and earlier
builds. Emulated digital inputs let you combine multiple possible keys
to trigger the buttons. This is OR logic, so you can map to eg
keyboard.up OR gamepad.up for instance. Emulated analog inputs always
sum together. Emulated rumble outputs will cause all mapped devices to
rumble, which is probably not at all useful but whatever. Hotkeys use
AND logic, so you have to press every key mapped to trigger them. Useful
for eg Ctrl+F to trigger fullscreen.

Obviously, there are cases where OR logic would be nice for hotkeys,
too. Eg if you want both F11 and your gamepad's guide button to trigger
the fullscreen toggle. Unfortunately, this isn't supported, and likely
won't ever be in tomoko. Something I might consider is a throw switch in
the configuration file to swap between AND or OR logic for hotkeys, but
I'm not going to allow construction of mappings like "(Keyboard.Ctrl and
Keyboard.F) or Gamepad.Guide", as that's just too complicated to code,
and too complicated to make a nice GUI to set up the mappings for.
2017-06-06 23:44:40 +10:00
Tim Allen 3bcf3c24c9 Update to v102r20 release.
byuu says:

Changelog:

  - nall: `#undef OUT` on Windows platform
  - GBA: add missing CPU prefetch state to serialization (this was
    breaking serialization in games using ROM prefetch)
  - GBA: reset all PPU data in the power() function (some things were
    missing before, causing issues on reset)
  - GBA: restored horizontal mosaic emulation to the new pixel-based
    renderer
  - GBA: fixed tilemap background horizontal flipping (Legend of Spyro -
    warning screen)
  - GBA: fixed d8 bits of scroll registers (ATV - Thunder Ridge Racers -
    menu screen)
  - SFC: DRAM refresh ticks the ALU MUL/DIV registers five steps forward
    [reported by kevtris]
  - SFC: merged dmaCounter and autoJoypadCounter into new shared
    clockCounter
      - left stub for old dmaCounter so that I can do some traces to
        ensure the new code's 100% identical

GBA save states would have been broken since whenever I emulated ROM
prefetch. I guess not many people are using the GBA core ...
2017-06-06 11:39:27 +10:00
Tim Allen 2461293ff0 Update to v102r19 release.
byuu says:

Note: add `#undef OUT` to the top of higan/gba/ppu/ppu.hpp to compile on
Windows (ugh ...) Now to await posts about this in four more threads
again ;)

Changelog:

  - GBA: rewrote PPU from a scanline-based renderer to a pixel-based
    renderer
  - ruby: fixed video/gdi bugs

Note that there's an approximately 21% speed penalty compared to v102r18
for the pixel-based renderer.

Also, horizontal mosaic effects are not yet implemented. But they should
be prior to v103. This one is a little tricky as it currently works on
fully rendered scanlines. I need to roll the mosaic into the background
renderers, and then for sprites, well ... see below.

The trickiest part by far of this new renderer is the object (sprite)
system. Unlike every other system I emulate, the GBA supports affine
rendering of its sprites. Or in other words, rotation effects. And it
also has a very complex priority system.

Right now, I can't see any way that the GBA PPU could render pixels in
real-time like this. My belief is that there's a 240-entry buffer that
fills up the next scanline's row of pixels. Which means it probably also
runs on the last scanline of Vblank so that the first scanline has
sprite data.

However, I didn't design my object renderer like this just yet. For now,
it creates a buffer of all 240 pixels right away at the start of the
scanline. I know\!\! That's technically scanline-based. But it's only
for fetching object tiledata, and it's only temporary.

What needs to happen is I need a way to run something like a "mini libco
thread" inside of the main thread, so that the object renderer can run
in parallel with the rest of the PPU, yet not be a hideous abomination
of a state machine, yet also not be horrendously slow as a full libco
thread would be.

I'm envisioning some kind of stackless yielding coroutine. But I'll need
to think through how to design that, given the absence of coroutines
even in C++17.
2017-06-04 13:16:44 +10:00
Tim Allen 1ca4609079 Update to v102r18 release.
byuu says:

This WIP fixes all the critical pending issues I had open. I'm sure
there's many more that simply didn't make their way into said list. So
by all means, please report important issues you're aware of so they can
get fixed.

Changelog:

  - ruby: add variable texture support to GDI video driver [bug
    reported by Cydrak]
  - ruby: minor cleanups to XShm video driver
  - ruby: fix handling of up+down, left+right hat cases for XInput
    driver [bug reported by Cydrak]
  - nall: fixed vector class so that compilation with GCC 7.1 should
    succeed [SuperMikeMan]
  - sfc: initialize most DSP registers to random values to fix Magical
    Drop [Jonas Quinn]
  - sfc: lower PPU brightness when luma=0 from 50% scale to 25% scale;
    helps scenes like Final Fantasy III's intro
2017-05-30 17:48:41 +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 1cab2dfeb8 Update to v102r11 release.
byuu says:

Changelog:

  - MD: connected 32KB cartridge RAM up to every Genesis game under 2MB
    loaded¹
  - MS, GG, MD: improved PSG noise channel emulation, hopefully²
  - MS, GG, MD: lowered PSG volume so that the lowpass doesn't clamp
    samples³
  - MD: added read/write handlers for VRAM, VSRAM, CRAM
  - MD: block VRAM copy when CD4 is clear⁴
  - MD: rewrote VRAM fill, VRAM copy to be byte-based⁵
  - MD: VRAM fill byte set should fall through to regular data port
    write handler⁶

¹: the header parsing for backup RAM is really weird. It's spaces
when not used, and seems to be 0x02000001-0x02003fff for the Shining
games. I don't understand why it starts at 0x02000001 instead of
0x02000000. So I'm just forcing every game to have 32KB of RAM for now.
There's also special handling for ROMs > 2MB that also have RAM
(Phantasy Star IV, etc) where there's a toggle to switch between ROM and
RAM. For now, that's not emulated.

I was hoping the Shining games would run after this, but they're still
dead-locking on me :(

²: Cydrak pointed out some flaws in my attempt to implement what he
had. I was having trouble understanding what he meant, so I went back
and read the docs on the sound chip and tried implementing the counter
the way the docs describe. Hopefully I have this right, but I don't know
of any good test ROMs to make sure my noise emulation is correct. The
docs say the shifted-out value goes to the output instead of the low bit
of the LFSR, so I made that change as well.

I think I hear the noise I'm supposed to in Sonic Marble Zone now, but
it seems like it's not correct in Green Hill Zone, adding a bit of an
annoying buzz to the background music. Maybe it sounds better with the
YM2612, but more likely, I still screwed something up :/

³: it's set to 50% range for both cores right now. For the MD, it
will need to be 25% once YM2612 emulation is in.

⁴: technically, this deadlocks the VDP until a hard reset. I could
emulate this, but for now I just don't do the VRAM copy in this case.

⁵: VSRAM fill and CRAM fill not supported in this new mode. They're
technically undocumented, and I don't have good notes on how they work.
I've been seeing conflicting notes on whether the VRAM fill buffer is
8-bits or 16-bits (I chose 8-bits), and on whether you write the low
byte and then high byte of each words, or the high byte and then low
byte (I chose the latter.)

The VRAM copy improvements fix the opening text in Langrisser II, so
that's great.

⁶: Langrisser II sets the transfer length to one less than needed to
fill the background letter tile on the scenario overview screen. After
moving to byte-sized transfers, a black pixel was getting stuck there.
So effectively, VRAM fill length becomes DMA length + 1, and the first
byte uses the data port so it writes a word value instead of just a byte
value. Hopefully this is all correct, although it probably gets way more
complicated with the VDP FIFO.
2017-02-25 22:11:46 +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 8071da4c6a Update to v102r09 release.
byuu says:

Changelog:

  - MD: restructured DMA to a subclass of VDP
  - MD: implemented VRAM copy mode (fixes Langrisser II ... mostly)
  - MS: implemened PSG support [Cydrak]
  - GG: implemented PSG stereo sound support
  - MS: use the new struct Model {} design that other cores use

The MS/GG PSG should be feature complete, but I don't have good tests
for Game Gear stereo mode, nor for the noise channel. There's also a
really weird behavior with when to reload the channel counters on volume
register writes. I can confirm what Cydrak observed in that following
the docs and reloading always creates serious audio distortion problems.
So, more research is needed there.

To get the correct sound out of the PSG, I have to run it at 3.58MHz /
16, which seems really weird to me. The docs make it sound like it's
supposed to run at the full 3.58MHz. If we can really run it at
223.7KHz, then that's help reduce the overhead of PSG emulation, which
will definitely come in handy for Mega Drive, and possibly later Mega
CD, emulation.

I have not implemented the PSG into the Mega Drive just yet. Nor have I
implemented save states or cheat code support into the MS/GG cores yet.
The latter is next on my list.
2017-02-21 22:07:33 +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 7c9b78b7bb Update to v102r07 release.
byuu says:

Changelog:

  - PCE: emulated PSG volume controls (vastly enhances audio quality)
  - PCE: emulated PSG noise as a square wave (somewhat enhances audio
    quality)
  - PCE: added save state support (currently broken and deadlocks the
    emulator though)

Thankfully, MAME had some rather easy to read code on how the volume
adjustment works, which they apparently ripped out of expired patents.
Hooray!

The two remaining sound issues are:

1. the random number generator for the noise channel is definitely not
hardware accurate. But it won't affect the sound quality at all. You'd
only be able to tell the difference by looking at hex bytes of a stream
rip.
2. I have no clue how to emulate the LFO (frequency modulation). A comment
in MAME's code (they also don't emulate it) advises that they aren't
aware of any games that even use it. But I'm there has to be at least one?

Given LFO not being used, and the RNG not really mattering all that much
... the sound's pretty close to perfect now.
2017-02-13 10:09:03 +11:00
Tim Allen fa6cbac251 Update to v102r06 release.
byuu says:

Changelog:

  - added higan/emulator/platform.hpp (moved out Emulator::Platform from
    emulator/interface.hpp)
  - moved gmake build paramter to nall/GNUmakefile; both higan and
    icarus use it now
  - added build=profile mode
  - MD: added the region select I/O register
  - MD: started to add region selection support internally (still no
    external select or PAL support)
  - PCE: added cycle stealing when reading/writing to the VDC or VCE;
    and when using ST# instructions
  - PCE: cleaned up PSG to match the behavior of Mednafen (doesn't
    improve sound at all ;_;)
      - note: need to remove loadWaveSample, loadWavePeriod
  - HuC6280: ADC/SBC decimal mode consumes an extra cycle; does not set
    V flag
  - HuC6280: block transfer instructions were taking one cycle too many
  - icarus: added code to strip out PC Engine ROM headers
  - hiro: added options support to BrowserDialog

The last one sure ended in failure. The plan was to put a region
dropdown directly onto hiro::BrowserDialog, and I had all the code for
it working. But I forgot one important detail: the system loads
cartridges AFTER powering on, so even though I could technically change
the system region post-boot, I'd rather not do so.

So that means we have to know what region we want before we even select
a game. Shit.
2017-02-11 10:56:42 +11:00
Tim Allen bf70044edc Update to v102r05 release.
byuu says:

Changelog:

  - higan: added Makefile option,
    `build=(release|debug|instrument|optimize)` , defaults to release
  - PCE: added preliminary PSG (sound) emulation

The Makefile thing is just to make it easier to build debug releases
without having to hand-edit the Makefile. Just say "gmake build=debug"
and you'll get -g, otherwise you'll get -O3 -s. I'll probably start
adding these build= blocks to my other projects. Or maybe I'll put it
into nall, in which case release will need a different name ... a stable
-01, and a fast -03 mode. I also want to add a mode to generate
profiling information (via gprof.)

Unfortunately, the existing documentation on the PCE's PSG is as
barebones as humanly possible.

Right now, I support waveform mode, direct D/A mode, and noise
generation mode. However for noise, I'm not actually generating a proper
square wave, and I don't know the PRNG algorithm used for choosing the
random values. So for now, I'm just feeding in nall::random() values to
it.

I'm also not sure about the noise mode's frequency counter. Magic Kit is
implying it's 64*~frequency, but that results in an 11-bit period. It
seems only logical that we'd want a 12-bit period. So my guess is that
it's actually 12-bit, and halfway through it alternates between two
randomly generated values every 32 samples, and the two values are
generated every time the period hits zero.

Next up, it's not clear when the period counter is reloaded, either for
the waveform or the noise mode. So for now, when enabling the channel, I
reload the waveform period. And when enabling noise mode, I reload the
noise period. I don't know if you need to do it when writing to the
frequency registers or not.

Next, it's not clear whether the period is a decrement-and-compare, or a
compare-and-decrement, and whether we reload with frequency,
frequency-1, or frequency+1. There's this cryptic note in
pcetext.txt:

> The PSG channel frequency is 12 bits, $001 is the highest frequency,
> $FFF is the next to lowest frequency, and $000 is the lowest frequency.

As best I can tell, he's trying to say that it's decrement-and-compare.

Whatever the case, there's periodic popping noises every few seconds. I
thought it might be because this is the first system with a fractional
sampling rate (~3.57MHz), but rounding the frequency to a whole number
doesn't help at all, and emulator/audio should be able to handle
fractional resampling rates anyway.

The popping noises could also be due to PSG writes being cycle-timed,
and my HuC6280 cycle timings not being very great yet. The PSG has no
kind of interrupts, so I think careful timing is the only way to do
certain things, especially D/A mode.

Next up, I really don't understand the frequency modulation mode at all.
I don't have any idea whatsoever how to support that. It also has a
frequency value that we'll need to understand how the period works and
reloads. Basic idea though is the channel 1 output turns into a value to
modulate channel 0's frequency by, and channel 1's output gets muted.

Next up, I don't know how the volume controls work at all. There's a
master volume left+right, per-channel volume left+right, and per-channel
overall volume. The documentation lists their effects in terms of
decibels. I have no fucking clue how to turn decibels into multiply-by
values. Let alone how to stack THREE levels of audio volume controls
>_>

Next, it looks like the output is always 5-bit unsigned per-channel, but
there's also all the volume adjustments. So I don't know the final
bit-depth of the final output to normalize the value into a signed
floating point value between -1.0 and +1.0. So for now, half the
potential speaker range (anything below zero) isn't used in the
generated output.

As bad as all this sounds, and it is indeed bad ... the audio's about
~75% correct, so you can definitely play games like this, it just won't
be all that much fun.
2017-02-10 08:56:59 +11:00
Tim Allen ee7662a8be Update to v102r04 release.
byuu says:

Changelog:
  - Super Game Boy support is functional once again
  - new GameBoy::SuperGameBoyInterface class
  - system.(dmg,cgb,sgb) is now Model::(Super)GameBoy(Color) ala the PC
    Engine
  - merged WonderSwanInterface, WonderSwanColorInterface shared
    functions to WonderSwan::Interface
  - merged GameBoyInterface, GameBoyColorInterface shared functions to
    GameBoy::Interface
  - Interface::unload() now calls Interface::save() for Master System,
    Game Gear, Mega Drive, PC Engine, SuperGrafx
  - PCE: emulated PCE-CD backup RAM; stored per-game as save.ram (2KiB
    file)
      - this means you can now save your progress in games like Neutopia
      - the PCE-CD I/O registers like BRAM write protect are not
        emulated yet
  - PCE: IRQ sources now hold the IRQ line state, instead of the CPU
    holding it
      - this fixes most SuperGrafx games, which were fighting over the
        VDC IRQ line previously
  - PCE: CPU I/O $14xx should return the pending IRQ bits even if IRQs
    are disabled
  - PCE: VCE and the VDCs now synchronize to each other; fixes pixel
    widths in all games
  - PCE: greatly increased the accuracy of the VPC priority selection
    code (windows may be buggy still)
  - HuC6280: PLA, PLX, PLY should set Z, N flags; fixes many game bugs
    [Jonas Quinn]

The big thing I wanted to do was enslave the VDC(s) to the VCE. But
unfortunately, I forgot about the asynchronous DMA channels that each
VDC supports, so this isn't going to be possible I'm afraid.

In the most demanding case, Daimakaimura in-game, we're looking at 85fps
on my Xeon E3 1276v3. So ... not great, and we don't even have sound
connected yet.

We are going to have to profile and optimize this code once sound
emulation and save states are in.

Basically, think of it like this: the VCE, VDC0, and VDC1 all have the
same overhead, scheduling wise (which is the bulk of the performance
loss) as the dot-renderer for the SNES core. So it's like there's three
bsnes-accuracy PPU threads running just for video.

-----

Oh, just a fair warning ... the hooks for the SGB are a work in
progress.

If anyone is working on higan or a fork and want to do something similar
to it, don't use it as a template, at least not yet.

Right now, higan looks like this:

  - Emulator::Video handles the platform→videoRefresh calls
  - Emulator::Audio handles the platform→audioSample calls
  - each core hard-codes the platform→inputPoll, inputRumble calls
  - each core hard-codes calls to path, open, load to process files
  - dipSettings and notify are specialty hacks, neither are even hooked
    up right now to anything

With the SGB, it's an emulation core inside an emulation core, so
ideally you want to hook all of those functions. Emulator::Video and
Emulator::Audio aren't really abstractions over that, as the GB core
calls them and we have to special case not calling them in SGB mode.

The path, open, load can be implemented without hooks, thanks to the UI
only using one instance of Emulator::Platform for all cores. All we have
to do is override the folder path ID for the "Game Boy.sys" folder, so
that it picks "Super Game Boy.sfc/" and loads its boot ROM instead.
That's just a simple argument to GameBoy::System::load() and we're done.

dipSettings, notify and inputRumble don't matter. But we do also have to
hook inputPoll as well.

The nice idea would be for SuperFamicom::ICD2 to inherit from
Emulator::Platform and provide the desired functions that we need to
overload. After that, we'd just need the GB core to keep an abstraction
over the global Emulator::platform\* handle, to select between the UI
version and the SFC::ICD2 version.

However ... that doesn't work because of Emulator::Video and
Emulator::Audio. They would also have to gain an abstraction over
Emulator::platform\*, and even worse ... you'd have to constantly swap
between the two so that the SFC core uses the UI, and the GB core uses
the ICD2.

And so, for right now, I'm checking Model::SuperGameBoy() -> bool
everywhere, and choosing between the UI and ICD2 targets that way. And
as such, the ICD2 doesn't really need Emulator::Platform inheritance,
although it certainly could do that and just use the functions it needs.

But the SGB is even weirder, because we need additional new signals
beyond just Emulator::Platform, like joypWrite(), etc.

I'd also like to work on the Emulator::Stream for the SGB core. I don't
see why we can't have the GB core create its own stream, and let the
ICD2 just use that instead. We just have to be careful about the ICD2's
CPU soft reset function, to make sure the GB core's Stream object
remains valid. What I think that needs is a way to release an
Emulator::Stream individually, rather than calling
Emulator::Audio::reset() to do it. They are shared\_pointer objects, so
I think if I added a destructor function to remove it from
Emulator::Audio::streams, then that should work.
2017-01-26 12:06:06 +11:00
Tim Allen 186f008574 Update to v102r03 release.
byuu says:

Changelog:

  - PCE: split VCE from VDC
  - HuC6280: changed bus from (uint21 addr) to (uint8 bank, uint13 addr)
  - added SuperGrafx emulation (adds secondary VDC, plus new VPC)

The VDC now has no concept of the actual display raster timing, and
instead is driven by Vpulse (start of frame) and Hpulse (start of
scanline) signals from the VCE. One still can't render the start of the
next scanline onto the current scanline through overly aggressive
timings, but it shouldn't be too much more difficult to allow that to
occur now. This process incurs quite a major speed hit, so low-end
systems with Atom CPUs can't run things at 60fps anymore.

The timing needs a lot of work. The pixels end up very jagged if the VCE
doesn't output batches of 2-4 pixels at a time. But this should not be a
requirement at all, so I'm not sure what's going wrong there.

Yo, Bro and the 512-width mode of TV Sports Basketball is now broken as
a result of these changes, and I'm not sure why.

To load SuperGrafx games, you're going to have to change the .pce
extensions to .sg or .sgx. Or you can manually move the games from the
PC Engine folder to the SuperGrafx folder and change the game folder
extensions. I have no way to tell the games apart. Mednafen uses CRC32
comparisons, and I may consider that since there's only five games, but
I'm not sure yet.

The only SuperGrafx game that's playable right now is Aldynes. And the
priorities are all screwed up. I don't understand how the windows or the
priorities work at all from sgxtech.txt, so ... yeah. It's pretty
broken, but it's a start.

I could really use some help with this, as I'm very lost right now with
rendering :/

-----

Note that the SuperGrafx is technically its own system, it's not an
add-on.

As such, I'm giving it a separate .sys folder, and a separate library.

There's debate over how to name this thing. "SuperGrafx" appears more
popular than "Super Grafx". And you might also call it the "PC Engine
SuperGrafx", but I decided to leave off the prefix so it appears more
distinct.
2017-01-24 08:18:54 +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 c40e9754bc Update to v102r01 release.
byuu says:

Changelog:

  - MS, MD, PCE: remove controllers from scheduler in destructor
    [hex_usr]
  - PCE: no controller should return all bits set (still causing errant
    key presses when swapping gamepads)
  - PCE: emulate MDR for hardware I/O $0800-$17ff
  - PCE: change video resolution to 1140x242
  - PCE: added tertiary background Vscroll register (secondary cache)
  - PCE: create classes out of VDC VRAM, SATB, CRAM for cleaner access
    and I/O registers
  - PCE: high bits of CRAM read should be set
  - PCE: partially emulated VCE display registers: color frequency, HDS,
    HDW, VDS, VDW
  - PCE: 32-width sprites now split to two 16-width sprites to handle
    overflow properly
  - PCE: hopefully emulated sprite zero hit correctly (it's not well
    documented, and not often used)
  - PCE: trigger line coincidence interrupts during the previous
    scanline's Hblank period
  - tomoko: raise viewport from 320x240 to 326x242 to accommodate PC
    Engine's max resolution
  - nall: workaround for Clang compilation bug that can't figure out
    that a char is an integral data type
2017-01-22 11:33:36 +11:00
Tim Allen ae5968cfeb Update to v102 release.
byuu says (in the public announcement):

This release adds very preliminary emulation of the Sega Master System
(Mark III), Sega Game Gear, Sega Mega Drive (Genesis), and NEC PC Engine
(Turbografx-16). These cores do not yet offer sound emulation, save
states or cheat codes.

I'm always very hesitant to release a new emulation core in its alpha
stages, as in the past this has resulted in lasting bad impressions
of cores that have since improved greatly. For instance, the Game Boy
Advance emulation offered today is easily the second most accurate around,
yet it is still widely judged by its much older alpha implementation.

However, it's always been tradition with higan to not hold onto code
in secret. Rather than delay future releases for another year or two,
I'll put my faith in you all to understand that the emulation of these
systems will improve over time.

I hope that by releasing things as they are now, I might be able to
receive some much needed assistance in improving these cores, as the
documentation for these new systems is very much less than ideal.

byuu says (in the WIP forum):

Changelog:

  - PCE: latch background scroll registers (fixes Neutopia scrolling)
  - PCE: clip background attribute table scrolling (fixes Blazing Lazers
    scrolling)
  - PCE: support background/sprite enable/disable bits
  - PCE: fix large sprite indexing (fixes Blazing Lazers title screen
    sprites)
  - HuC6280: wrap zeropage accesses to never go beyond $20xx
  - HuC6280: fix alternating addresses for block move instructions
    (fixes Neutopia II)
  - HuC6280: block move instructions save and restore A,X,Y registers
  - HuC6280: emulate BCD mode (may not be 100% correct, based on SNES
    BCD) (fixes Blazing Lazers scoring)
2017-01-20 08:01:15 +11:00
Tim Allen b03563426f Update to v101r35 release.
byuu says:

Changelog:
  - PCE: added 384KB HuCard ROM mirroring mode
  - PCE: corrected D-pad polling order
  - PCE: corrected palette color ordering (GRB, not RGB -- yes,
    seriously)
  - PCE: corrected SATB DMA -- should write to SATB, not to VRAM
  - PCE: broke out Background, Sprite VDC settings to separate
    subclasses
  - PCE: emulated VDC backgrounds
  - PCE: emulated VDC sprites
  - PCE: emulated VDC sprite overflow, collision interrupts
  - HuC6280: fixed disassembler output for STi instructions
  - HuC6280: added missing LastCycle check to interrupt()
  - HuC6280: fixed BIT, CMP, CPX, CPY, TRB, TSB, TST flag testing and
    result
  - HuC6280: added extra cycle delays to the block move instructions
  - HuC6280: fixed ordering for flag set/clear instructions (happens
    after LastCycle check)
  - HuC6280: removed extra cycle from immediate instructions
  - HuC6280: fixed indirectLoad, indirectYStore absolute addressing
  - HuC6280: fixed BBR, BBS zeropage value testing
  - HuC6280: fixed stack push/pull direction

Neutopia looks okay until the main title screen, then there's some
gibberish on the bottom. The game also locks up with some gibberish once
you actually start a new game. So, still not playable just yet =(
2017-01-19 19:38:57 +11:00
Tim Allen f500426158 Update to v101r34 release.
byuu says:

Changelog:

  - PCE: emulated gamepad polling
  - PCE: emulated CPU interrupt sources
  - PCE: emulated timer
  - PCE: smarter emulation of ST0,ST1,ST2 instructions
  - PCE: better structuring of CPU, VDP IO registers
  - PCE: connected palette generation to the interface
  - PCE: emulated basic VDC timing
  - PCE: emulated VDC Vblank, Coincidence, and DMA completion IRQs
  - PCE: emulated VRAM, SATB DMA transfers
  - PCE: emulated VDC I/O registers

Everything I've implemented today likely has lots of bugs, and is
untested for obvious reasons.

So basically, after I fix many horrendous bugs, it should now be
possible to implement the VDC and start getting graphical output.
2017-01-17 08:02:56 +11:00
Tim Allen 8499c64756 Update to v101r33 release.
byuu says:

Changelog:

  - PCE: HuC6280 core completed

There's bound to be a countless stream of bugs, and the cycle counts are
almost certainly not exact yet, but ... all instructions are implemented.

So at this point, I can start comparing trace logs against Mednafen's
debugger output.

Of course, we're very likely to immediately slam into a wall of needing
I/O registers implemented for the VDC in order to proceed further.
2017-01-15 11:58:47 +11:00
Tim Allen 26bd7590ad Update to v101r32 release.
byuu says:

Changelog:

  - SMS: fixed controller connection bug
  - SMS: fixed Z80 reset bug
  - PCE: emulated HuC6280 MMU
  - PCE: emulated HuC6280 RAM
  - PCE: emulated HuCard ROM reading
  - PCE: implemented 178 instructions
  - tomoko: removed "soft reset" functionality
  - tomoko: moved "power cycle" to just above "unload" option

I'm not sure of the exact number of HuC6280 instructions, but it's less
than 260.

Many of the ones I skipped are HuC6280-originals that I don't know how
to emulate just yet.

I'm also really unsure about the zero page stuff. I believe we should be
adding 0x2000 to the addresses to hit page 1, which is supposed to be
mapped to the zero page (RAM). But when I look at turboEMU's source, I
have no clue how the hell it could possibly be doing that. It looks to
be reading from page 0, which is almost always ROM, which would be ...
really weird.

I also don't know if I've emulated the T mode opcodes correctly or not.
The documentation on them is really confusing.
2017-01-14 10:59:38 +11:00
Tim Allen 21ee597aae Add a `.gitlab-ci.yml` to automate WIP builds. 2017-01-13 12:18:25 +11:00
Tim Allen bf90bdfcc8 Update to v101r31 release.
byuu says:

Changelog:

  - converted Emulator::Interface::Bind to Emulator::Platform
  - temporarily disabled SGB hooks
  - SMS: emulated Game Gear palette (latching word-write behavior not
    implemented yet)
  - SMS: emulated Master System 'Reset' button, Game Gear 'Start' button
  - SMS: removed reset() functionality, driven by the mappable input now
    instead
  - SMS: split interface class in two: one for Master System, one for
    Game Gear
  - SMS: emulated Game Gear video cropping to 160x144
  - PCE: started on HuC6280 CPU core—so far only registers, NOP
    instruction has been implemented

Errata:

  - Super Game Boy support is broken and thus disabled
  - if you switch between Master System and Game Gear without
    restarting, bad things happen:
      - SMS→GG, no video output on the GG
      - GG→SMS, no input on the SMS

I'm not sure what's causing the SMS\<-\>GG switch bug, having a hard
time debugging it. Help would be very much appreciated, if anyone's up
for it. Otherwise I'll keep trying to track it down on my end.
2017-01-13 12:15:45 +11:00
Tim Allen 0ad70a30f8 Update to v101r30 release.
byuu says:

Changelog:

  - SMS: added cartridge ROM/RAM mirroring (fixes Alex Kidd)
  - SMS: fixed 8x16 sprite mode (fixes Wonder Boy, Ys graphics)
  - Z80: emulated "ex (sp),hl" instruction
  - Z80: fixed INx NF (should be set instead of cleared)
  - Z80: fixed loop condition check for CPxR, INxR, LDxR, OTxR (fixes
    walking in Wonder Boy)
  - SFC: removed Debugger and sfc/debugger.hpp
  - icarus: connected MS, GG, MD importing to the scan dialog
  - PCE: added emulation skeleton to higan and icarus

At this point, Master System games are fairly highly compatible, sans
audio. Game Gear games are running, but I need to crop the resolution
and support the higher color palette that they can utilize. It's really
something else the way they handled the resolution shrink on that thing.

The last change is obviously going to be the biggest news.

I'm very well aware it's not an ideal time to start on a new emulation
core, with the MS and MD cores only just now coming to life with no
audio support.

But, for whatever reason, my heart's really set on working on the PC
Engine. I wanted to write the final higan skeleton core, and get things
ready so that whenever I'm in the mood to work on the PCE, I can do so.

The skeleton is far and away the most tedious and obnoxious part of the
emulator development, because it's basically all just lots of
boilerplate templated code, lots of new files to create, etc.

I really don't know how things are going to proceed ... but I can say
with 99.9% certainty that this will be the final brand new core ever
added to higan -- at least one written by me, that is. This was
basically the last system from my childhood that I ever cared about.
It's the last 2D system with games that I really enjoy playing. No other
system is worth dividing my efforts and reducing the quality and amount
of time to work on the systems I have.

In the future, there will be potential for FDS, Mega CD and PCE-CD
support. But those will all be add-ons, and they'll all be really
difficult and challenge the entire design of higan's UI (it's entirely
cartridge-driven at this time.) None of them will be entirely new cores
like this one.
2017-01-12 07:27:30 +11:00
Tim Allen 79c83ade70 Update to v101r29 release.
byuu says:

Changelog:

  - SMS: background VDP clips partial tiles on the left (math may not be
    right ... it's hard to reason about)
  - SMS: fix background VDP scroll locks
  - SMS: fix VDP sprite coordinates
  - SMS: paint black after the end of the visible display
      - todo: shouldn't be a brute force at the end of the main VDP
        loop, should happen in each rendering unit
  - higan: removed emulator/debugger.hpp
  - higan: removed privileged: access specifier
  - SFC: removed debugger hooks
      - todo: remove sfc/debugger.hpp
  - Z80: fixed disassembly of (fd,dd) cb (displacement) (opcode)
    instructions
  - Z80: fix to prevent interrupts from firing between ix/iy prefixes
    and opcodes
      - todo: this is a rather hacky fix that could, if exploited, crash
        the stack frame
  - Z80: fix BIT flags
  - Z80: fix ADD hl,reg flags
  - Z80: fix CPD, CPI flags
  - Z80: fix IND, INI flags
  - Z80: fix INDR, INIT loop flag check
  - Z80: fix OUTD, OUTI flags
  - Z80: fix OTDR, OTIR loop flag check
2017-01-10 08:27:13 +11:00
Tim Allen a3aea95e6b Update to v101r28 release.
byuu says:

Changelog:

  - SMS: emulated the remaining 240 instructions in the (0xfd, 0xdd)
    0xcb (displacement) (opcode) set
      - 1/8th of these were "legal" instructions, and apparently games
        use them a lot
  - SMS: emulated the standard gamepad controllers
      - reset button not emulated yet

The reset button is tricky. In every other case, reset is a hardware
thing that instantly reboots the entire machine.

But on the SMS, it's more like a gamepad button that's attached to the
front of the device. When you press it, it fires off a reset vector
interrupt and the gamepad polling routine lets you query the status of
the button.

Just having a reset option in the "Master System" hardware menu is not
sufficient to fully emulate the behavior. Even more annoying is that the
Game Gear doesn't have such a button, yet the core information structs
aren't flexible enough for the Master System to have it, and the Game
Gear to not have it, in the main menu. But that doesn't matter anyway,
since it won't work having it in the menu for the Master System.

So as a result, I'm going to have to have a new "input device" called
"Hardware" that has the "Reset" button listed under there. And for the
sake of consistency, I'm not sure if we should treat the other systems
the same way or not :/
2017-01-09 07:55:02 +11:00
Tim Allen 569f5abc28 Update to v101r27 release.
byuu says:

Changelog:

  - SMS: emulated the generic Sega memory mapper (none of the more
    limited forms of it yet)
      - (missing ROM shift, ROM write enable emulation -- no commercial
        games use either, though)
  - SMS: bus I/O returns 0xff instead of 0x00 so games don't think every
    key is being pressed at once
      - (this is a hack until I implement proper controller pad reading)
  - SMS: very limited protection against reading/writing past the end of
    ROM/RAM (todo: should mirror)
  - SMS: VDP background HSCROLL subtracts, rather than adds, to the
    offset (unlike VSCROLL)
  - SMS: VDP VSCROLL is 9-bit, modulates voffset+vscroll to 224 in
    192-line mode (32x28 tilemap)
  - SMS: VDP tiledata for backgrounds and sprites use `7-(x&7)` rather
    than `(x&7)`
  - SMS: fix output color to be 6-bit rather than 5-bit
  - SMS: left clip uses register `#7`, not palette color `#7`
      - (todo: do we want `color[reg7]` or `color[16 + reg7]`?)
  - SMS: refined handling of 0xcb, 0xed prefixes in the Z80 core and its
    disassembler
  - SMS: emulated (0xfd, 0xdd) 0xcb opcodes 0x00-0x0f (still missing
    0x10-0xff)
  - SMS: fixed 0xcb 0b-----110 opcodes to use direct HL and never allow
    (IX,IY)+d
  - SMS: fixed major logic bug in (IX,IY)+d displacement
      - (was using `read(x)` instead of `operand()` for the displacement
        byte fetch before)
  - icarus: fake there always being 32KiB of RAM in all SMS cartridges
    for the time being
      - (not sure how to detect this stuff yet; although I've read it's
        not even really possible `>_>`)

TODO: remove processor/z80/dissassembler.cpp code block at line 396 (as it's unnecessary.)

Lots of commercial games are starting to show trashed graphical output now.
2017-01-06 19:11:38 +11:00
Tim Allen 5bdf55f08f Update to v101r25 release.
byuu says:

Changelog:

  - SMS: emulated VDP mode 4 graphical output (background, sprites)
  - added $(windres) to icarus as well

I'm sure the VDP emulation is still really, really buggy, but
essentially I handle:

  - mode 4 rendering
  - background scrolling
  - background hscroll lock
  - background vscroll lock
  - background nametable relocation
  - sprite nametable relocation
  - sprite tiledata relocation
  - sprite 192-line y=0xd0 edge case (end sprite rendering)
  - sprite 8-pixel x-coordinate displacement
  - sprite extended size (height only in mode 4)
  - sprite overflow
  - sprite collision
  - left column masking
  - display disable
  - backdrop color
  - 192, 224, 240 height

I do not support:

  - mode 2 rendering
  - sprite zoom
  - disallowing 240 height in NTSC mode
  - PAL mode
  - probably lots more
2016-12-30 18:24:35 +11:00
Tim Allen e30780bb72 Update to v101r25 release.
byuu says:

Changelog:

  - Makefile: added $(windres), -lpthread to Windows port
  - GBA: WAITCNT.prefetch is not writable (should fix Donkey Kong: King
    of Swing) \[endrift\]
  - SMS: fixed hcounter shift value \[hex\_usr\]
  - SMS: emulated interrupts (reset button isn't hooked up anywhere, not
    sure where to put it yet)

This WIP actually took a really long time because the documentation on
SMS interrupts was all over the place. I'm hoping I've emulated them
correctly, but I honestly have no idea. It's based off my best
understanding from four or five different sources. So it's probably
quite buggy.

However, a few interrupts fire in Sonic the Hedgehog, so that's
something to start with. Now I just have to hope I've gotten some games
far enough in that I can start seeing some data in the VDP VRAM. I need
that before I can start emulating graphics mode 4 to get some actual
screen output.

Or I can just say to hell with it and use a "Hello World" test ROM.
That'd probably be smarter.
2016-12-26 23:11:08 +11:00
Tim Allen bab2ac812a Update to v101r24 release.
byuu says:

Changelog:

  - SMS: extended bus mapping of in/out ports: now decoding them fully
    inside ms/bus
  - SMS: moved Z80 disassembly code from processor/z80 to ms/cpu
    (cosmetic)
  - SMS: hooked up non-functional silent PSG sample generation, so I can
    cap the framerate at 60fps
  - SMS: hooked up the VDP main loop: 684 clocks/scanline, 262
    scanlines/frame (no PAL support yet)
  - SMS: emulated the VDP Vcounter and Hcounter polling ... hopefully
    it's right, as it's very bizarre
  - SMS: emulated VDP in/out ports (data read, data write, status read,
    control write, register write)
  - SMS: decoding and caching all VDP register flags (variable names
    will probably change)
  - nall: \#undef IN on Windows port (prevent compilation warning on
    processor/z80)

Watching Sonic the Hedgehog, I can definitely see some VDP register
writes going through, which is a good sign.

Probably the big thing that's needed before I can get enough into the
VDP to start showing graphics is interrupt support. And interrupts are
never fun to figure out :/

What really sucks on this front is I'm flying blind on the Z80 CPU core.
Without a working VDP, I can't run any Z80 test ROMs to look for CPU
bugs. And the CPU is certainly too buggy still to run said test ROM
anyway. I can't find any SMS emulators with trace logging from reset.
Such logs vastly accelerate tracking down CPU logic bugs, so without
them, it's going to take a lot longer.
2016-12-17 22:31:34 +11:00
Tim Allen 1d7b674dd4 Update to v101r23 release.
byuu says:

This is a really tiny WIP. Just wanted to add the known fixes before I start debugging it against Mednafen in a fork.

Changelog:

  - Z80: fixed flag calculations on 8-bit ADC, ADD, SBC, SUB
  - Z80: fixed flag calculations on 16-bit ADD
  - Z80: simplified DAA logic \[AWJ\]
  - Z80: RETI sets IFF1=IFF2 (same as RETN)
2016-11-15 18:20:42 +11:00
Tim Allen c2c957a9da Update to v101r22 release.
byuu says:

Changelog:
- Z80: all 25 remaining instructions implemented

Now onto the debugging ... :/
2016-11-01 22:42:25 +11:00
Tim Allen 8cf20dabbf Update to v101r21 release.
byuu says:

Changelog:

- Z80: emulated 83 new instructions
- Z80: timing improvements

DAA is a skeleton implementation to complete the normal opcode set. Also
worth noting that I don't know exactly what the hell RETI is doing,
so for now it acts like RET. RETN probably needs some special handling
besides just setting IFF1=IFF2 as well.

I'm now missing 24 ED-prefix instructions, plus DAA, for a total of 25
opcodes remaining. And then, of course, several weeks worth of debugging
all of the inevitable bugs in the core.
2016-11-01 08:10:33 +11:00
Tim Allen 2707c5316d Update to v101r20 release.
byuu says:

Changelog:
- Z80: emulated 272 new instructions
- hiro/GTK: fixed v101r19 Linux regression [thanks, SuperMikeMan!]
2016-10-29 11:33:30 +11:00
Tim Allen f3e67da937 Update to v101r19 release.
byuu says:

Changelog:

-   added \~130 new PAL games to icarus (courtesy of Smarthuman
    and aquaman)
-   added all three Korean-localized games to icarus
-   sfc: removed SuperDisc emulation (it was going nowhere)
-   sfc: fixed MSU1 regression where the play/repeat flags were not
    being cleared on track select
-   nall: cryptography support added; will be used to sign future
    databases (validation will always be optional)
-   minor shims to fix compilation issues due to nall changes

The real magic is that we now have 25-30% of the PAL SNES library in
icarus!

Signing will be tricky. Obviously if I put the public key inside the
higan archive, then all anyone has to do is change that public key for
their own releases. And if you download from my site (which is now over
HTTPS), then you don't need the signing to verify integrity. I may just
put the public key on my site on my site and leave it at that, we'll
see.
2016-10-28 08:16:58 +11:00
Tim Allen c6fc15f8d2 Update to v101r18 release.
byuu says:

Changelog:

  - added 30 new PAL games to icarus (courtesy of Mikerochip)
  - new version of libco no longer requires mprotect nor W|X permissions
  - nall: default C compiler to -std=c11 instead of -std=c99
  - nall: use `-fno-strict-aliasing` during compilation
  - updated nall/certificates (hopefully for the last time)
  - updated nall/http to newer coding conventions
  - nall: improve handling of range() function

I didn't really work on higan at all, this is mostly just a release
because lots of other things have changed.

The most interesting is `-fno-strict-aliasing` ... basically, it joins
`-fwrapv` as being "stop the GCC developers from doing *really* evil
shit that could lead to security vulnerabilities or instabilities."

For the most part, it's a ~2% speed penalty for higan. Except for the
Sega Genesis, where it's a ~10% speedup. I have no idea how that's
possible, but clearly something's going very wrong with strict aliasing
on the Genesis core.

So ... it is what it is. If you need the performance for the non-Genesis
cores, you can turn it off in your builds. But I'm getting quite sick of
C++'s "surprises" and clever compiler developers, so I'm keeping it on
in all of my software going forward.
2016-09-14 21:55:53 +10:00
Tim Allen d6e9d94ec3 Update to v101r17 release.
byuu says:

Changelog:

  - Z80: added most opcodes between 0x00 and 0x3f (two or three hard
    ones missing still)
  - Z80: redid register declaration *again* to handle AF', BC', DE',
    HL' (ugggggh, the fuck? Alternate registers??)
      - basically, using `#define <register name>` values to get around
        horrendously awful naming syntax
  - Z80: improved handling of displace() so that it won't ever trigger
    on (BC) or (DE)
2016-09-06 23:53:14 +10:00
Tim Allen 2fbbccf985 Update to v101r16 release.
byuu says:

Changelog:

  - Z80: implemented 113 new instructions (all the easy
    LD/ADC/ADD/AND/OR/SBC/SUB/XOR ones)
  - Z80: used alternative to castable<To, With> type (manual cast inside
    instruction() register macros)
  - Z80: debugger: used register macros to reduce typing and increase
    readability
  - Z80: debugger: smarter way of handling multiple DD/FD prefixes
    (using gotos, yay!)
  - ruby: fixed crash with Windows input driver on exit (from SuperMikeMan)

I have no idea how the P/V flag is supposed to work on AND/OR/XOR, so
that's probably wrong for now. HALT is also mostly a dummy function for
now. But I typically implement those inside instruction(), so it
probably won't need to be changed? We'll see.
2016-09-06 10:09:33 +10:00
Tim Allen 4c3f58150c Update to v101r15 release.
byuu says:

Changelog:

  - added (poorly-named) castable<To, With> template
  - Z80 debugger rewritten to make declaring instructions much simpler
  - Z80 has more instructions implemented; supports displacement on
    (IX), (IY) now
  - added `Processor::M68K::Bus` to mirror `Processor::Z80::Bus`
      - it does add a pointer indirection; so I'm not sure if I want to
        do this for all of my emulator cores ...
2016-09-04 23:51:27 +10:00
Tim Allen d91f3999cc Update to v101r14 release.
byuu says:
Changelog:

  - rewrote the Z80 core to properly handle 0xDD (IX0 and 0xFD (IY)
    prefixes
  - added Processor::Z80::Bus as a new type of abstraction
  - all of the instructions implemented have their proper T-cycle counts
    now
  - added nall/certificates for my public keys

The goal of `Processor::Z80::Bus` is to simulate the opcode fetches being
2-read + 2-wait states; operand+regular reads/writes being 3-read. For
now, this puts the cycle counts inside the CPU core. At the moment, I
can't think of any CPU core where this wouldn't be appropriate. But it's
certainly possible that such a case exists. So this may not be the
perfect solution.

The reason for having it be a subclass of Processor::Z80 instead of
virtual functions for the MasterSystem::CPU core to define is due to
naming conflicts. I wanted the core to say `in(addr)` and have it take
the four clocks. But I also wanted a version of the function that didn't
consume time when called. One way to do that would be for the core to
call `Z80::in(addr)`, which then calls the regular `in(addr)` that goes to
`MasterSystem::CPU::in(addr)`. But I don't want to put the `Z80::`
prefix on all of the opcodes. Very easy to forget it, and then end up not
consuming any time. Another is to use uglier names in the
`MasterSystem::CPU` core, like `read_`, `write_`, `in_`, `out_`, etc. But,
yuck.

So ... yeah, this is an experiment. We'll see how it goes.
2016-09-03 21:26:04 +10:00
Tim Allen 7c96826eb0 Update to v101r13 release.
byuu says:

Changelog:

  - MS: added ms/bus
  - Z80: implemented JP/JR/CP/DI/IM/IN instructions
  - MD/VDP: added window layer emulation
  - MD/controller/gamepad: fixed d2,d3 bits (Altered Beast requires
    this)

The Z80 is definitely a lot nastier than the LR35902. There's a lot of
table duplication with HL→IX→IY; and two of them nest two levels deep
(eg FD CB xx xx), so the design may change as I implement more.
2016-08-27 14:48:21 +10:00
Tim Allen 5df717ff2a Update to v101r12 release.
byuu says:

Changelog:

  - new md/bus/ module for bus reads/writes
      - abstracts byte/word accesses wherever possible (everything but
        RAM; forces all but I/O to word, I/O to byte)
      - holds the system RAM since that's technically not part of the
        CPU anyway
  - added md/controller and md/system/peripherals
  - added emulation of gamepads
  - added stub PSG audio output (silent) to cap the framerate at 60fps
    with audio sync enabled
  - fixed VSRAM reads for plane vertical scrolling (two bugs here: add
    instead of sub; interlave plane A/B)
  - mask nametable read offsets (can't exceed 8192-byte nametables
    apparently)
  - emulated VRAM/VSRAM/CRAM reads from VDP data port
  - fixed sprite width/height size calculations
  - added partial emulation of 40-tile per scanline limitation (enough
    to fix Sonic's title screen)
  - fixed off-by-one sprite range testing
  - fixed sprite tile indexing
  - Vblank happens at Y=224 with overscan disabled
      - unsure what happens when you toggle it between Y=224 and Y=240
        ... probably bad things
  - fixed reading of address register for ADDA, CMPA, SUBA
  - fixed sign extension for MOVEA effect address reads
  - updated MOVEM to increment the read addresses (but not writeback)
    for (aN) mode

With all of that out of the way, we finally have Sonic the Hedgehog
(fully?) playable. I played to stage 1-2 and through the special stage,
at least. EDIT: yeah, we probably need HIRQs for Labyrinth Zone.

Not much else works, of course. Most games hang waiting on the Z80, and
those that don't (like Altered Beast) are still royally screwed. Tons of
features still missing; including all of the Z80/PSG/YM2612.

A note on the perihperals this time around: the Mega Drive EXT port is
basically identical to the regular controller ports. So unlike with the
Famicom and Super Famicom, I'm inheriting the exension port from the
controller class.
2016-08-22 08:11:24 +10:00
Tim Allen f7ddbfc462 Update to v101r11 release.
byuu says:

Changelog:

  - 68K: fixed NEG/NEGX operand order
  - 68K: fixed bug in disassembler that was breaking trace logging
  - VDP: improved sprite rendering (still 100% broken)
  - VDP: added horizontal/vertical scrolling (90% broken)

Forgot:

  - 68K: fix extension word sign bit on indexed modes for disassembler
    as well
  - 68K: emulate STOP properly (use r.stop flag; clear on IRQs firing)

I'm really wearing out fast here. The Genesis documentation is somehow
even worse than Game Boy documentation, but this is a far more complex
system.

It's a massive time sink to sit here banging away at every possible
combination of how things could work, only to see no positive
improvements. Nothing I do seems to get sprites to do a goddamn thing.

squee says the sprite Y field is 10-bits, X field is 9-bits. genvdp says
they're both 10-bits. BlastEm treats them like they're both 10-bits,
then masks off the upper bit so it's effectively 9-bits anyway.

Nothing ever bothers to tell you whether the horizontal scroll values
are supposed to add or subtract from the current X position. Probably
the most basic detail you could imagine for explaining horizontal
scrolling and yet ... nope. Nothing.

I can't even begin to understand how the VDP FIFO functionality works,
or what the fuck is meant by "slots".

I'm completely at a loss as how how in the holy hell the 68K works with
8-bit accesses. I don't know whether I need byte/word handlers for every
device, or if I can just hook it right into the 68K core itself. This
one's probably the most major design detail. I need to know this before
I go and implement the PSG/YM2612/IO ports-\>gamepads/Z80/etc.

Trying to debug the 68K is murder because basically every game likes to
start with a 20,000,000-instruction reset phase of checksumming entire
games, and clearing out the memory as agonizingly slowly as humanly
possible. And like the ARM, there's too many registers so I'd need three
widescreen monitors to comfortably view the entire debugger output lines
onscreen.

I can't get any test ROMs to debug functionality outside of full games
because every **goddamned** test ROM coder thinks it's acceptable to tell
people to go fetch some toolchain from a link that died in the late '90s
and only works on MS-DOS 6.22 to build their fucking shit, because god
forbid you include a 32KiB assembled ROM image in your fucking archives.

... I may have to take a break for a while. We'll see.
2016-08-21 12:50:05 +10:00
Tim Allen 0b70a01b47 Update to v101r10 release.
byuu says:
Changelog:

  - 68K: MOVEQ is 8-bit signed
  - 68K: disassembler was print EOR for OR instructions
  - 68K: address/program-counter indexed mode had the signed-word/long
    bit backward
  - 68K: ADDQ/SUBQ #n,aN always works in long mode; regardless of size
  - 68K→VDP DMA needs to use `mode.bit(0)<<22|dmaSource`; increment by
    one instead of two
  - Z80: added registers and initial two instructions
  - MS: hooked up enough to load and start running games
      - Sonic the Hedgehog can execute exactly one instruction... whoo.
2016-08-20 00:11:26 +10:00
Tim Allen 4d2e17f9c0 Update to v101r09 release.
byuu says:

Sorry, two WIPs in one day. Got excited and couldn't wait.

Changelog:

  - ADDQ, SUBQ shouldn't update flags when targeting an address register
  - ADDA should sign extend effective address reads
  - JSR was pushing the PC too early
  - some improvements to 8-bit register reads on the VDP (still needs
    work)
  - added H/V counter reads to the VDP IO port region
  - icarus: added support for importing Master System and Game Gear ROMs
  - tomoko: added library sub-menus for each manufacturer
      - still need to sort Game Gear after Mega Drive somehow ...

The sub-menu system actually isn't all that bad. It is indeed a bit more
annoying, but not as annoying as I thought it was going to be. However,
it looks a hell of a lot nicer now.
2016-08-18 08:05:50 +10:00