byuu says:
Enough to get through the BIOS and into cartridge ROM.
I am a bit annoyed that I was basically told that the GBA PPU wasn't
that bad. Sprites are a clusterfuck, easily worse than Mode7, docs don't
even begin to explain them in enough detail.
This is going to be fun.
byuu says:
Added all of the above fixes and changes. [A lot of individual fixes for
the ARM core from Cydrak - Ed.] Also new is pipeline_decode() to fetch
data, and IME/IE/IF support, and an ARM::processor.irqline flag that
triggers IRQs at 0x18. Only Vblank is hooked up, which is what SWI 4 was
waiting on previously.
I'm sure my interrupt support is horribly broken and wrong. I was never
able to really figure out IE/IF on the Game Boy, so there's no question
this is even worse.
It's now going crazy and writing 0 to IE forever now after the Vblank
IRQ triggers.
byuu says:
Added some more ARM opcodes, hooked up MMIO. Bind it with mmio[(addr
000-3ff)] = this; inside CPU/PPU/APU, goes to read(), write().
Also moved the Hitachi HG51B core to processor/, and split it apart from
the snes/chip/hitachidsp implementation.
This one actually worked really well. Very clean split between MMIO/DMA
and the processor core. I may move a more generic DMA function inside
the core, not sure yet.
I still believe the HG51B169 to be a variant of the HG51BS family, but
given they're meant to be incredibly flexible microcontrollers, it's
possible that each variant gets its own instruction set.
So, who knows. We'll worry about it if we ever find another HG51B DSP,
I guess.
GBA BIOS is constantly reading from 04000300, but it never writes. If
I return prng()&1, I can get it to proceed until it hits a bad opcode
(stc opcode, which the GBA lacks a coprocessor so ... bad codepath.)
Without it, it just reads that register forever and keeps resetting the
system, or something ...
I guess we're going to have to try and get ARMwrestler working, because
the BIOS seems to need too much emulation code to do anything at all.
There was a "v087r07pre" release that I unfortunately missed.
byuu says (about v087r07pre):
Creates the bsnes/processor folder. This has a shared ARM core there
which both the GBA and ST018 inherit.
There are going to be separate decoders, and revision-specific checks,
to support the differences between v3+.
In the future, I also want to move the other processor cores here:
- GBZ80 (GB, GBC)
- 65816 (SNES CPU, SA-1)
- NEC uPD (7725, 96050, maybe 7720 just for fun)
- Hitachi HG51B169
- SuperFX
- SPC700
- 65(C?)02
Basically, the GBA/ST018 forces my hand to start coding a bit more like
a multi-system emulator.
Right now, the ST018 is broken. Hence the pre. Apparently the GBA core
being used now has some bugs. So this'll be a nice way to stress-test
the GBA core a bit before we make it to ARMwrestler.
byuu says (about v087r07):
Both snes/chip/armdsp and gba/cpu use processor/arm now.
Fixed THUMB to execute the BL prefix and suffix separately. I can now
get the GBA BIOS stuck in some kind of infinite loop. Hooray ...
I guess?
Tim Allen