bsnes/higan/gba/cpu/cpu.cpp

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#include <gba/gba.hpp>
namespace GameBoyAdvance {
#include "prefetch.cpp"
#include "bus.cpp"
Update to v099r13 release. byuu says: Changelog: - GB core code cleanup completed - GBA core code cleanup completed - some more cleanup on missed processor/arm functions/variables - fixed FC loading icarus bug - "Load ROM File" icarus functionality restored - minor code unification efforts all around (not perfect yet) - MMIO->IO - mmio.cpp->io.cpp - read,write->readIO,writeIO It's been a very long work in progress ... starting all the way back with v094r09, but the major part of the higan code cleanup is now completed! Of course, it's very important to note that this is only for the basic style: - under_score functions and variables are now camelCase - return-type function-name() are now auto function-name() -> return-type - Natural<T>/Integer<T> replace (u)intT_n types where possible - signed/unsigned are now int/uint - most of the x==true,x==false tests changed to x,!x A lot of spot improvements to consistency, simplicity and quality have gone in along the way, of course. But we'll probably never fully finishing beautifying every last line of code in the entire codebase. Still, this is a really great start. Going forward, WIP diffs should start being smaller and of higher quality once again. I know the joke is, "until my coding style changes again", but ... this was way too stressful, way too time consuming, and way too risky. I'm too old and tired now for extreme upheavel like this again. The only major change I'm slowly mulling over would be renaming the using Natural<T>/Integer<T> = (u)intT; shorthand to something that isn't as easily confused with the (u)int_t types ... but we'll see. I'll definitely continue to change small things all the time, but for the larger picture, I need to just accept the style I have and live with it.
2016-06-29 11:10:28 +00:00
#include "io.cpp"
#include "memory.cpp"
#include "dma.cpp"
#include "timer.cpp"
#include "serialization.cpp"
CPU cpu;
CPU::CPU() {
iwram = new uint8[ 32 * 1024];
ewram = new uint8[256 * 1024];
regs.dma[0].source.resize(27); regs.dma[0].run.source.resize(27);
regs.dma[0].target.resize(27); regs.dma[0].run.target.resize(27);
regs.dma[0].length.resize(14); regs.dma[0].run.length.resize(14);
regs.dma[1].source.resize(28); regs.dma[1].run.source.resize(28);
regs.dma[1].target.resize(27); regs.dma[1].run.target.resize(27);
regs.dma[1].length.resize(14); regs.dma[1].run.length.resize(14);
regs.dma[2].source.resize(28); regs.dma[2].run.source.resize(28);
regs.dma[2].target.resize(27); regs.dma[2].run.target.resize(27);
regs.dma[2].length.resize(14); regs.dma[2].run.length.resize(14);
regs.dma[3].source.resize(28); regs.dma[3].run.source.resize(28);
regs.dma[3].target.resize(28); regs.dma[3].run.target.resize(28);
regs.dma[3].length.resize(16); regs.dma[3].run.length.resize(16);
}
CPU::~CPU() {
delete[] iwram;
delete[] ewram;
}
auto CPU::Enter() -> void {
while(true) scheduler.synchronize(), cpu.main();
}
auto CPU::main() -> void {
#if defined(DEBUG)
if(crash) {
print(cpsr().t ? disassemble_thumb_instruction(pipeline.execute.address)
: disassemble_arm_instruction(pipeline.execute.address), "\n");
print(disassemble_registers(), "\n");
print("Executed: ", instructions, "\n");
while(true) step(frequency);
}
#endif
processor.irqline = regs.ime && (regs.irq.enable & regs.irq.flag);
if(regs.mode == Registers::Mode::Stop) {
if(!(regs.irq.enable & regs.irq.flag & Interrupt::Keypad)) {
Update to v099r13 release. byuu says: Changelog: - GB core code cleanup completed - GBA core code cleanup completed - some more cleanup on missed processor/arm functions/variables - fixed FC loading icarus bug - "Load ROM File" icarus functionality restored - minor code unification efforts all around (not perfect yet) - MMIO->IO - mmio.cpp->io.cpp - read,write->readIO,writeIO It's been a very long work in progress ... starting all the way back with v094r09, but the major part of the higan code cleanup is now completed! Of course, it's very important to note that this is only for the basic style: - under_score functions and variables are now camelCase - return-type function-name() are now auto function-name() -> return-type - Natural<T>/Integer<T> replace (u)intT_n types where possible - signed/unsigned are now int/uint - most of the x==true,x==false tests changed to x,!x A lot of spot improvements to consistency, simplicity and quality have gone in along the way, of course. But we'll probably never fully finishing beautifying every last line of code in the entire codebase. Still, this is a really great start. Going forward, WIP diffs should start being smaller and of higher quality once again. I know the joke is, "until my coding style changes again", but ... this was way too stressful, way too time consuming, and way too risky. I'm too old and tired now for extreme upheavel like this again. The only major change I'm slowly mulling over would be renaming the using Natural<T>/Integer<T> = (u)intT; shorthand to something that isn't as easily confused with the (u)int_t types ... but we'll see. I'll definitely continue to change small things all the time, but for the larger picture, I need to just accept the style I have and live with it.
2016-06-29 11:10:28 +00:00
syncStep(16); //STOP does not advance timers
} else {
regs.mode = Registers::Mode::Normal;
}
return;
}
Update to v099r13 release. byuu says: Changelog: - GB core code cleanup completed - GBA core code cleanup completed - some more cleanup on missed processor/arm functions/variables - fixed FC loading icarus bug - "Load ROM File" icarus functionality restored - minor code unification efforts all around (not perfect yet) - MMIO->IO - mmio.cpp->io.cpp - read,write->readIO,writeIO It's been a very long work in progress ... starting all the way back with v094r09, but the major part of the higan code cleanup is now completed! Of course, it's very important to note that this is only for the basic style: - under_score functions and variables are now camelCase - return-type function-name() are now auto function-name() -> return-type - Natural<T>/Integer<T> replace (u)intT_n types where possible - signed/unsigned are now int/uint - most of the x==true,x==false tests changed to x,!x A lot of spot improvements to consistency, simplicity and quality have gone in along the way, of course. But we'll probably never fully finishing beautifying every last line of code in the entire codebase. Still, this is a really great start. Going forward, WIP diffs should start being smaller and of higher quality once again. I know the joke is, "until my coding style changes again", but ... this was way too stressful, way too time consuming, and way too risky. I'm too old and tired now for extreme upheavel like this again. The only major change I'm slowly mulling over would be renaming the using Natural<T>/Integer<T> = (u)intT; shorthand to something that isn't as easily confused with the (u)int_t types ... but we'll see. I'll definitely continue to change small things all the time, but for the larger picture, I need to just accept the style I have and live with it.
2016-06-29 11:10:28 +00:00
dmaRun();
if(regs.mode == Registers::Mode::Halt) {
if(!(regs.irq.enable & regs.irq.flag)) {
step(16);
} else {
regs.mode = Registers::Mode::Normal;
}
return;
}
exec();
}
auto CPU::step(uint clocks) -> void {
Update to v099r13 release. byuu says: Changelog: - GB core code cleanup completed - GBA core code cleanup completed - some more cleanup on missed processor/arm functions/variables - fixed FC loading icarus bug - "Load ROM File" icarus functionality restored - minor code unification efforts all around (not perfect yet) - MMIO->IO - mmio.cpp->io.cpp - read,write->readIO,writeIO It's been a very long work in progress ... starting all the way back with v094r09, but the major part of the higan code cleanup is now completed! Of course, it's very important to note that this is only for the basic style: - under_score functions and variables are now camelCase - return-type function-name() are now auto function-name() -> return-type - Natural<T>/Integer<T> replace (u)intT_n types where possible - signed/unsigned are now int/uint - most of the x==true,x==false tests changed to x,!x A lot of spot improvements to consistency, simplicity and quality have gone in along the way, of course. But we'll probably never fully finishing beautifying every last line of code in the entire codebase. Still, this is a really great start. Going forward, WIP diffs should start being smaller and of higher quality once again. I know the joke is, "until my coding style changes again", but ... this was way too stressful, way too time consuming, and way too risky. I'm too old and tired now for extreme upheavel like this again. The only major change I'm slowly mulling over would be renaming the using Natural<T>/Integer<T> = (u)intT; shorthand to something that isn't as easily confused with the (u)int_t types ... but we'll see. I'll definitely continue to change small things all the time, but for the larger picture, I need to just accept the style I have and live with it.
2016-06-29 11:10:28 +00:00
timerStep(clocks);
syncStep(clocks);
}
Update to v099r13 release. byuu says: Changelog: - GB core code cleanup completed - GBA core code cleanup completed - some more cleanup on missed processor/arm functions/variables - fixed FC loading icarus bug - "Load ROM File" icarus functionality restored - minor code unification efforts all around (not perfect yet) - MMIO->IO - mmio.cpp->io.cpp - read,write->readIO,writeIO It's been a very long work in progress ... starting all the way back with v094r09, but the major part of the higan code cleanup is now completed! Of course, it's very important to note that this is only for the basic style: - under_score functions and variables are now camelCase - return-type function-name() are now auto function-name() -> return-type - Natural<T>/Integer<T> replace (u)intT_n types where possible - signed/unsigned are now int/uint - most of the x==true,x==false tests changed to x,!x A lot of spot improvements to consistency, simplicity and quality have gone in along the way, of course. But we'll probably never fully finishing beautifying every last line of code in the entire codebase. Still, this is a really great start. Going forward, WIP diffs should start being smaller and of higher quality once again. I know the joke is, "until my coding style changes again", but ... this was way too stressful, way too time consuming, and way too risky. I'm too old and tired now for extreme upheavel like this again. The only major change I'm slowly mulling over would be renaming the using Natural<T>/Integer<T> = (u)intT; shorthand to something that isn't as easily confused with the (u)int_t types ... but we'll see. I'll definitely continue to change small things all the time, but for the larger picture, I need to just accept the style I have and live with it.
2016-06-29 11:10:28 +00:00
auto CPU::syncStep(uint clocks) -> void {
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 03:56:12 +00:00
Thread::step(clocks);
synchronize(ppu);
synchronize(apu);
}
Update to v099r13 release. byuu says: Changelog: - GB core code cleanup completed - GBA core code cleanup completed - some more cleanup on missed processor/arm functions/variables - fixed FC loading icarus bug - "Load ROM File" icarus functionality restored - minor code unification efforts all around (not perfect yet) - MMIO->IO - mmio.cpp->io.cpp - read,write->readIO,writeIO It's been a very long work in progress ... starting all the way back with v094r09, but the major part of the higan code cleanup is now completed! Of course, it's very important to note that this is only for the basic style: - under_score functions and variables are now camelCase - return-type function-name() are now auto function-name() -> return-type - Natural<T>/Integer<T> replace (u)intT_n types where possible - signed/unsigned are now int/uint - most of the x==true,x==false tests changed to x,!x A lot of spot improvements to consistency, simplicity and quality have gone in along the way, of course. But we'll probably never fully finishing beautifying every last line of code in the entire codebase. Still, this is a really great start. Going forward, WIP diffs should start being smaller and of higher quality once again. I know the joke is, "until my coding style changes again", but ... this was way too stressful, way too time consuming, and way too risky. I'm too old and tired now for extreme upheavel like this again. The only major change I'm slowly mulling over would be renaming the using Natural<T>/Integer<T> = (u)intT; shorthand to something that isn't as easily confused with the (u)int_t types ... but we'll see. I'll definitely continue to change small things all the time, but for the larger picture, I need to just accept the style I have and live with it.
2016-06-29 11:10:28 +00:00
auto CPU::keypadRun() -> void {
Update to v098r11 release. byuu says: Changelog: - fixed nall/path.hpp compilation issue - fixed ruby/audio/xaudio header declaration compilation issue (again) - cleaned up xaudio2.hpp file to match my coding syntax (12.5% of the file was whitespace overkill) - added null terminator entry to nall/windows/utf8.hpp argc[] array - nall/windows/guid.hpp uses the Windows API for generating the GUID - this should stop all the bug reports where two nall users were generating GUIDs at the exact same second - fixed hiro/cocoa compilation issue with uint# types - fixed major higan/sfc Super Game Boy audio latency issue - fixed higan/sfc CPU core bug with pei, [dp], [dp]+y instructions - major cleanups to higan/processor/r65816 core - merged emulation/native-mode opcodes - use camel-case naming on memory.hpp functions - simplify address masking code for memory.hpp functions - simplify a few opcodes themselves (avoid redundant copies, etc) - rename regs.* to r.* to match modern convention of other CPU cores - removed device.order<> concept from Emulator::Interface - cores will now do the translation to make the job of the UI easier - fixed plurality naming of arrays in Emulator::Interface - example: emulator.ports[p].devices[d].inputs[i] - example: vector<Medium> media - probably more surprises Major show-stoppers to the next official release: - we need to work on GB core improvements: LY=153/0 case, multiple STAT IRQs case, GBC audio output regs, etc. - we need to re-add software cursors for light guns (Super Scope, Justifier) - after the above, we need to fix the turbo button for the Super Scope I really have no idea how I want to implement the light guns. Ideally, we'd want it in higan/video, so we can support the NES Zapper with the same code. But this isn't going to be easy, because only the SNES knows when its output is interlaced, and its resolutions can vary as {256,512}x{224,240,448,480} which requires pixel doubling that was hard-coded to the SNES-specific behavior, but isn't appropriate to be exposed in higan/video.
2016-05-25 11:13:02 +00:00
//lookup table to convert button indexes to Emulator::Interface indexes
static const uint lookup[] = {5, 4, 8, 9, 3, 2, 0, 1, 7, 6};
if(!regs.keypad.control.enable) return;
bool test = regs.keypad.control.condition; //0 = OR, 1 = AND
for(auto n : range(10)) {
Update to v098r11 release. byuu says: Changelog: - fixed nall/path.hpp compilation issue - fixed ruby/audio/xaudio header declaration compilation issue (again) - cleaned up xaudio2.hpp file to match my coding syntax (12.5% of the file was whitespace overkill) - added null terminator entry to nall/windows/utf8.hpp argc[] array - nall/windows/guid.hpp uses the Windows API for generating the GUID - this should stop all the bug reports where two nall users were generating GUIDs at the exact same second - fixed hiro/cocoa compilation issue with uint# types - fixed major higan/sfc Super Game Boy audio latency issue - fixed higan/sfc CPU core bug with pei, [dp], [dp]+y instructions - major cleanups to higan/processor/r65816 core - merged emulation/native-mode opcodes - use camel-case naming on memory.hpp functions - simplify address masking code for memory.hpp functions - simplify a few opcodes themselves (avoid redundant copies, etc) - rename regs.* to r.* to match modern convention of other CPU cores - removed device.order<> concept from Emulator::Interface - cores will now do the translation to make the job of the UI easier - fixed plurality naming of arrays in Emulator::Interface - example: emulator.ports[p].devices[d].inputs[i] - example: vector<Medium> media - probably more surprises Major show-stoppers to the next official release: - we need to work on GB core improvements: LY=153/0 case, multiple STAT IRQs case, GBC audio output regs, etc. - we need to re-add software cursors for light guns (Super Scope, Justifier) - after the above, we need to fix the turbo button for the Super Scope I really have no idea how I want to implement the light guns. Ideally, we'd want it in higan/video, so we can support the NES Zapper with the same code. But this isn't going to be easy, because only the SNES knows when its output is interlaced, and its resolutions can vary as {256,512}x{224,240,448,480} which requires pixel doubling that was hard-coded to the SNES-specific behavior, but isn't appropriate to be exposed in higan/video.
2016-05-25 11:13:02 +00:00
if(!regs.keypad.control.flag[n]) continue;
bool input = platform->inputPoll(0, 0, lookup[n]);
if(regs.keypad.control.condition == 0) test |= input;
if(regs.keypad.control.condition == 1) test &= input;
}
if(test) regs.irq.flag |= Interrupt::Keypad;
}
auto CPU::power() -> void {
create(CPU::Enter, 16'777'216);
ARM::power();
for(auto n : range( 32 * 1024)) iwram[n] = 0;
for(auto n : range(256 * 1024)) ewram[n] = 0;
for(auto& dma : regs.dma) {
dma.source = 0;
dma.target = 0;
dma.length = 0;
dma.data = 0;
dma.control.targetmode = 0;
dma.control.sourcemode = 0;
dma.control.repeat = 0;
dma.control.size = 0;
dma.control.drq = 0;
dma.control.timingmode = 0;
dma.control.irq = 0;
dma.control.enable = 0;
Update to v087r30 release. byuu says: Changelog: - DMA channel masks added (some are 27-bit source/target and some are 14-bit length -- hooray, varuint_t class.) - No more state.pending flags. Instead, we set dma.pending flag when we want a transfer (fixes GBA Video - Pokemon audio) [Cydrak] - fixed OBJ Vmosaic [Cydrak, krom] - OBJ cannot read <=0x13fff in BG modes 3-5 (fixes the garbled tile at the top-left of some games) - DMA timing should be much closer to hardware now, but probably not perfect - PPU frame blending uses blargg's bit-perfect, rounded method (slower, but what can you do?) - GBA carts really unload now - added nall/gba/cartridge.hpp: used when there is no manifest. Scans ROMs for library tags, and selects the first valid one found - added EEPROM auto-detection when EEPROM size=0. Forces disk/save state size to 8192 (otherwise states could crash between pre and post detect.) - detects first read after a set read address command when the size is zero, and sets all subsequent bit-lengths to that value, prints detected size to terminal - added nall/nes/cartridge.hpp: moves iNES detection out of emulation core. Important to note: long-term goal is to remove all nall/(system)/cartridge.hpp detections from the core and replace with databases. All in good time. Anyway, the GBA workarounds should work for ~98.5% of the library, if my pre-scanning was correct (~40 games with odd tags. I reject ones without numeric versions now, too.) I think we're basically at a point where we can release a new version now. Compatibility should be relatively high (at least for a first release), and fixes are only going to affect one or two games at a time. I'd like to start doing some major cleaning house internally (rename NES->Famicom, SNES->SuperFamicom and such.) Would be much wiser to do that on a .01 WIP to minimize regressions. The main problems with a release now: - speed is pretty bad, haven't really optimized much yet (not sure how much we can improve it yet, this usually isn't easy) - sound isn't -great-, but the GBA audio sucks anyway :P - couple of known bugs (Sonic X video, etc.)
2012-04-22 10:49:19 +00:00
dma.pending = 0;
dma.run.target = 0;
dma.run.source = 0;
dma.run.length = 0;
}
for(auto& timer : regs.timer) {
timer.period = 0;
timer.reload = 0;
timer.pending = false;
timer.control.frequency = 0;
timer.control.cascade = 0;
timer.control.irq = 0;
timer.control.enable = 0;
}
for(auto& flag : regs.keypad.control.flag) flag = 0;
regs.keypad.control.enable = 0;
regs.keypad.control.condition = 0;
regs.ime = 0;
regs.irq.enable = 0;
regs.irq.flag = 0;
for(auto& nwait : regs.wait.control.nwait) nwait = 0;
for(auto& swait : regs.wait.control.swait) swait = 0;
regs.wait.control.phi = 0;
regs.wait.control.prefetch = 0;
regs.wait.control.gametype = 0; //0 = GBA, 1 = GBC
regs.postboot = 0;
regs.mode = Registers::Mode::Normal;
regs.clock = 0;
regs.memory.control.disable = 0;
regs.memory.control.unknown1 = 0;
regs.memory.control.ewram = 1;
regs.memory.control.ewramwait = 13;
regs.memory.control.unknown2 = 0;
pending.dma.vblank = 0;
pending.dma.hblank = 0;
pending.dma.hdma = 0;
active.dma = false;
Update to v099r13 release. byuu says: Changelog: - GB core code cleanup completed - GBA core code cleanup completed - some more cleanup on missed processor/arm functions/variables - fixed FC loading icarus bug - "Load ROM File" icarus functionality restored - minor code unification efforts all around (not perfect yet) - MMIO->IO - mmio.cpp->io.cpp - read,write->readIO,writeIO It's been a very long work in progress ... starting all the way back with v094r09, but the major part of the higan code cleanup is now completed! Of course, it's very important to note that this is only for the basic style: - under_score functions and variables are now camelCase - return-type function-name() are now auto function-name() -> return-type - Natural<T>/Integer<T> replace (u)intT_n types where possible - signed/unsigned are now int/uint - most of the x==true,x==false tests changed to x,!x A lot of spot improvements to consistency, simplicity and quality have gone in along the way, of course. But we'll probably never fully finishing beautifying every last line of code in the entire codebase. Still, this is a really great start. Going forward, WIP diffs should start being smaller and of higher quality once again. I know the joke is, "until my coding style changes again", but ... this was way too stressful, way too time consuming, and way too risky. I'm too old and tired now for extreme upheavel like this again. The only major change I'm slowly mulling over would be renaming the using Natural<T>/Integer<T> = (u)intT; shorthand to something that isn't as easily confused with the (u)int_t types ... but we'll see. I'll definitely continue to change small things all the time, but for the larger picture, I need to just accept the style I have and live with it.
2016-06-29 11:10:28 +00:00
for(uint n = 0x0b0; n <= 0x0df; n++) bus.io[n] = this; //DMA
for(uint n = 0x100; n <= 0x10f; n++) bus.io[n] = this; //Timers
for(uint n = 0x120; n <= 0x12b; n++) bus.io[n] = this; //Serial
for(uint n = 0x130; n <= 0x133; n++) bus.io[n] = this; //Keypad
for(uint n = 0x134; n <= 0x159; n++) bus.io[n] = this; //Serial
for(uint n = 0x200; n <= 0x209; n++) bus.io[n] = this; //System
for(uint n = 0x300; n <= 0x301; n++) bus.io[n] = this; //System
//0x080-0x083 mirrored via gba/memory/memory.cpp //System
}
}