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Honours the region by implementing Japanese (no BIOS) and European (PAL) paths.

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This commit is contained in:
Thomas Harte 2018-10-19 21:37:05 -04:00
parent f9a6c00493
commit 6fff514901
1 changed files with 30 additions and 13 deletions
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43
Machines/MasterSystem/MasterSystem.cpp
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@ -80,14 +80,18 @@ class ConcreteMachine:
public:
ConcreteMachine(const Analyser::Static::Sega::Target &target, const ROMMachine::ROMFetcher &rom_fetcher) :
model_(target.model),
region_(target.region),
paging_scheme_(target.paging_scheme),
z80_(*this),
sn76489_(
(target.model == Analyser::Static::Sega::Target::Model::SG1000) ? TI::SN76489::Personality::SN76489 : TI::SN76489::Personality::SMS,
(target.model == Target::Model::SG1000) ? TI::SN76489::Personality::SN76489 : TI::SN76489::Personality::SMS,
audio_queue_,
sn76489_divider),
speaker_(sn76489_) {
speaker_.set_input_rate(3579545.0f / static_cast<float>(sn76489_divider));
set_clock_rate(3579545);
// Pick the clock rate based on the region.
const double clock_rate = target.region == Target::Region::Europe ? 3546893.0 : 3579540.0;
speaker_.set_input_rate(static_cast<float>(clock_rate / sn76489_divider));
set_clock_rate(clock_rate);
// Instantiate the joysticks.
joysticks_.emplace_back(new Joystick);
@ -106,8 +110,8 @@ class ConcreteMachine:
}
page_cartridge();
// Establish the BIOS (if relevant) and RAM.
if(target.model == Analyser::Static::Sega::Target::Model::MasterSystem) {
// Load the BIOS if relevant.
if(has_bios()) {
const auto roms = rom_fetcher("MasterSystem", {"bios.sms"});
if(!roms[0]) {
throw ROMMachine::Error::MissingROMs;
@ -115,8 +119,10 @@ class ConcreteMachine:
roms[0]->resize(8*1024);
memcpy(&bios_, roms[0]->data(), roms[0]->size());
map(read_pointers_, bios_, 8*1024, 0);
}
// Map RAM.
if(model_ == Target::Model::MasterSystem) {
map(read_pointers_, ram_, 8*1024, 0xc000, 0x10000);
map(write_pointers_, ram_, 8*1024, 0xc000, 0x10000);
} else {
@ -124,6 +130,7 @@ class ConcreteMachine:
map(write_pointers_, ram_, 1024, 0xc000, 0x10000);
}
// Apple a relatively low low-pass filter. More guidance needed here.
speaker_.set_high_frequency_cutoff(8000);
}
@ -132,7 +139,10 @@ class ConcreteMachine:
}
void setup_output(float aspect_ratio) override {
vdp_.reset(new TI::TMS::TMS9918(model_ == Analyser::Static::Sega::Target::Model::SG1000 ? TI::TMS::TMS9918A : TI::TMS::SMSVDP));
vdp_.reset(new TI::TMS::TMS9918(model_ == Target::Model::SG1000 ? TI::TMS::TMS9918A : TI::TMS::SMSVDP));
vdp_->set_tv_standard(
(region_ == Target::Region::Europe) ?
TI::TMS::TMS9918::TVStandard::PAL : TI::TMS::TMS9918::TVStandard::NTSC);
get_crt()->set_video_signal(Outputs::CRT::VideoSignal::Composite);
}
@ -222,7 +232,7 @@ class ConcreteMachine:
case CPU::Z80::PartialMachineCycle::Output:
switch(address & 0xc1) {
case 0x00:
if(model_ == Analyser::Static::Sega::Target::Model::MasterSystem) {
if(model_ == Target::Model::MasterSystem) {
// TODO: Obey the RAM enable.
memory_control_ = *cycle.value;
page_cartridge();
@ -253,7 +263,7 @@ class ConcreteMachine:
time_until_interrupt_ = vdp_->get_time_until_interrupt();
break;
case 0xc0:
LOG("TODO: [output] I/O port A/N; " << *cycle.value);
LOG("TODO: [output] I/O port A/N; " << int(*cycle.value));
break;
case 0xc1:
LOG("TODO: [output] I/O port B/misc");
@ -312,7 +322,10 @@ class ConcreteMachine:
vdp_->run_for(time_since_vdp_update_.flush());
}
Analyser::Static::Sega::Target::Model model_;
using Target = Analyser::Static::Sega::Target;
Target::Model model_;
Target::Region region_;
Target::PagingScheme paging_scheme_;
CPU::Z80::Processor<ConcreteMachine, false, false> z80_;
std::unique_ptr<TI::TMS::TMS9918> vdp_;
@ -345,8 +358,9 @@ class ConcreteMachine:
uint8_t paging_registers_[3] = {0, 1, 2};
uint8_t memory_control_ = 0;
void page_cartridge() {
// Either install the cartridge or don't.
if(!(memory_control_ & 0x40)) {
// Either install the cartridge or don't; Japanese machines can't see
// anything but the cartridge.
if(!(memory_control_ & 0x40) || region_ == Target::Region::Japan) {
for(size_t c = 0; c < 3; ++c) {
const size_t start_addr = (paging_registers_[c] * 0x4000) % cartridge_.size();
map(
@ -363,10 +377,13 @@ class ConcreteMachine:
}
// Throw the BIOS on top if this machine has one and it isn't disabled.
if(model_ == Analyser::Static::Sega::Target::Model::MasterSystem && !(memory_control_ & 0x08)) {
if(has_bios() && !(memory_control_ & 0x08)) {
map(read_pointers_, bios_, 8*1024, 0);
}
}
bool has_bios() {
return model_ == Target::Model::MasterSystem && region_ != Target::Region::Japan;
}
};
}