mirror of
https://github.com/TomHarte/CLK.git
synced 2024-07-16 22:28:57 +00:00
589 lines
18 KiB
C++
589 lines
18 KiB
C++
//
|
||
// Macintosh.cpp
|
||
// Clock Signal
|
||
//
|
||
// Created by Thomas Harte on 03/05/2019.
|
||
// Copyright © 2019 Thomas Harte. All rights reserved.
|
||
//
|
||
|
||
#include "Macintosh.hpp"
|
||
|
||
#include <array>
|
||
|
||
#include "DeferredAudio.hpp"
|
||
#include "DriveSpeedAccumulator.hpp"
|
||
#include "Keyboard.hpp"
|
||
#include "RealTimeClock.hpp"
|
||
#include "SonyDrive.hpp"
|
||
#include "Video.hpp"
|
||
|
||
#include "../../CRTMachine.hpp"
|
||
#include "../../KeyboardMachine.hpp"
|
||
#include "../../MediaTarget.hpp"
|
||
#include "../../MouseMachine.hpp"
|
||
|
||
#include "../../../Inputs/QuadratureMouse/QuadratureMouse.hpp"
|
||
|
||
//#define LOG_TRACE
|
||
|
||
#include "../../../Components/6522/6522.hpp"
|
||
#include "../../../Components/8530/z8530.hpp"
|
||
#include "../../../Components/DiskII/IWM.hpp"
|
||
#include "../../../Processors/68000/68000.hpp"
|
||
|
||
#include "../../../Analyser/Static/Macintosh/Target.hpp"
|
||
|
||
#include "../../Utility/MemoryPacker.hpp"
|
||
#include "../../Utility/MemoryFuzzer.hpp"
|
||
|
||
namespace {
|
||
|
||
const int CLOCK_RATE = 7833600;
|
||
|
||
}
|
||
|
||
namespace Apple {
|
||
namespace Macintosh {
|
||
|
||
template <Analyser::Static::Macintosh::Target::Model model> class ConcreteMachine:
|
||
public Machine,
|
||
public CRTMachine::Machine,
|
||
public MediaTarget::Machine,
|
||
public MouseMachine::Machine,
|
||
public CPU::MC68000::BusHandler,
|
||
public KeyboardMachine::MappedMachine {
|
||
public:
|
||
using Target = Analyser::Static::Macintosh::Target;
|
||
|
||
ConcreteMachine(const Target &target, const ROMMachine::ROMFetcher &rom_fetcher) :
|
||
mc68000_(*this),
|
||
iwm_(CLOCK_RATE),
|
||
video_(ram_, audio_, drive_speed_accumulator_),
|
||
via_(via_port_handler_),
|
||
via_port_handler_(*this, clock_, keyboard_, video_, audio_, iwm_, mouse_),
|
||
drives_{
|
||
{CLOCK_RATE, model >= Analyser::Static::Macintosh::Target::Model::Mac512ke},
|
||
{CLOCK_RATE, model >= Analyser::Static::Macintosh::Target::Model::Mac512ke}
|
||
},
|
||
mouse_(1) {
|
||
|
||
// Select a ROM name and determine the proper ROM and RAM sizes
|
||
// based on the machine model.
|
||
using Model = Analyser::Static::Macintosh::Target::Model;
|
||
std::string rom_name;
|
||
uint32_t ram_size, rom_size;
|
||
switch(model) {
|
||
default:
|
||
case Model::Mac128k:
|
||
ram_size = 128*1024;
|
||
rom_size = 64*1024;
|
||
rom_name = "mac128k.rom";
|
||
break;
|
||
case Model::Mac512k:
|
||
ram_size = 512*1024;
|
||
rom_size = 64*1024;
|
||
rom_name = "mac512k.rom";
|
||
break;
|
||
case Model::Mac512ke:
|
||
case Model::MacPlus:
|
||
ram_size = 512*1024;
|
||
rom_size = 128*1024;
|
||
rom_name = "macplus.rom";
|
||
break;
|
||
}
|
||
ram_mask_ = (ram_size >> 1) - 1;
|
||
rom_mask_ = (rom_size >> 1) - 1;
|
||
video_.set_ram_mask(ram_mask_);
|
||
|
||
// Grab a copy of the ROM and convert it into big-endian data.
|
||
const auto roms = rom_fetcher("Macintosh", { rom_name });
|
||
if(!roms[0]) {
|
||
throw ROMMachine::Error::MissingROMs;
|
||
}
|
||
roms[0]->resize(rom_size);
|
||
Memory::PackBigEndian16(*roms[0], rom_);
|
||
|
||
// Randomise memory contents.
|
||
Memory::Fuzz(ram_, sizeof(ram_) / sizeof(*ram_));
|
||
|
||
// Attach the drives to the IWM.
|
||
iwm_.iwm.set_drive(0, &drives_[0]);
|
||
iwm_.iwm.set_drive(1, &drives_[1]);
|
||
|
||
// The Mac runs at 7.8336mHz.
|
||
set_clock_rate(double(CLOCK_RATE));
|
||
audio_.speaker.set_input_rate(float(CLOCK_RATE));
|
||
|
||
// Insert any supplied media.
|
||
insert_media(target.media);
|
||
}
|
||
|
||
~ConcreteMachine() {
|
||
audio_.queue.flush();
|
||
}
|
||
|
||
void set_scan_target(Outputs::Display::ScanTarget *scan_target) override {
|
||
video_.set_scan_target(scan_target);
|
||
}
|
||
|
||
Outputs::Speaker::Speaker *get_speaker() override {
|
||
return &audio_.speaker;
|
||
}
|
||
|
||
void run_for(const Cycles cycles) override {
|
||
mc68000_.run_for(cycles);
|
||
}
|
||
|
||
using Microcycle = CPU::MC68000::Microcycle;
|
||
|
||
HalfCycles perform_bus_operation(const Microcycle &cycle, int is_supervisor) {
|
||
// time_since_video_update_ += cycle.length;
|
||
iwm_.time_since_update += cycle.length;
|
||
|
||
// The VIA runs at one-tenth of the 68000's clock speed, in sync with the E clock.
|
||
// See: Guide to the Macintosh Hardware Family p149 (PDF p188).
|
||
via_clock_ += cycle.length;
|
||
via_.run_for(via_clock_.divide(HalfCycles(10)));
|
||
|
||
// The keyboard also has a clock, albeit a very slow one — 100,000 cycles/second.
|
||
// Its clock and data lines are connected to the VIA.
|
||
keyboard_clock_ += cycle.length;
|
||
const auto keyboard_ticks = keyboard_clock_.divide(HalfCycles(CLOCK_RATE / 100000));
|
||
if(keyboard_ticks > HalfCycles(0)) {
|
||
keyboard_.run_for(keyboard_ticks);
|
||
via_.set_control_line_input(MOS::MOS6522::Port::B, MOS::MOS6522::Line::Two, keyboard_.get_data());
|
||
via_.set_control_line_input(MOS::MOS6522::Port::B, MOS::MOS6522::Line::One, keyboard_.get_clock());
|
||
}
|
||
|
||
// Feed mouse inputs within at most 1250 cycles of each other.
|
||
time_since_mouse_update_ += cycle.length;
|
||
const auto mouse_ticks = time_since_mouse_update_.divide(HalfCycles(2500));
|
||
if(mouse_ticks > HalfCycles(0)) {
|
||
mouse_.prepare_step();
|
||
scc_.set_dcd(0, mouse_.get_channel(1) & 1);
|
||
scc_.set_dcd(1, mouse_.get_channel(0) & 1);
|
||
}
|
||
|
||
// TODO: SCC should be clocked at a divide-by-two, if and when it actually has
|
||
// anything connected.
|
||
|
||
// Consider updating the real-time clock.
|
||
real_time_clock_ += cycle.length;
|
||
auto ticks = real_time_clock_.divide_cycles(Cycles(CLOCK_RATE)).as_int();
|
||
while(ticks--) {
|
||
clock_.update();
|
||
// TODO: leave a delay between toggling the input rather than using this coupled hack.
|
||
via_.set_control_line_input(MOS::MOS6522::Port::A, MOS::MOS6522::Line::Two, true);
|
||
via_.set_control_line_input(MOS::MOS6522::Port::A, MOS::MOS6522::Line::Two, false);
|
||
}
|
||
|
||
// Update the video. TODO: only on demand.
|
||
video_.run_for(cycle.length);
|
||
via_.set_control_line_input(MOS::MOS6522::Port::A, MOS::MOS6522::Line::One, !video_.vsync());
|
||
|
||
// Update interrupt input. TODO: move this into a VIA/etc delegate callback?
|
||
// Double TODO: does this really cascade like this?
|
||
if(scc_.get_interrupt_line()) {
|
||
mc68000_.set_interrupt_level(2);
|
||
} else if(via_.get_interrupt_line()) {
|
||
mc68000_.set_interrupt_level(1);
|
||
} else {
|
||
mc68000_.set_interrupt_level(0);
|
||
}
|
||
// mc68000_.set_interrupt_level(
|
||
// (via_.get_interrupt_line() ? 1 : 0) |
|
||
// (scc_.get_interrupt_line() ? 2 : 0)
|
||
// /* TODO: to emulate a programmer's switch: have it set bit 2 when pressed. */
|
||
// );
|
||
|
||
// A null cycle leaves nothing else to do.
|
||
if(cycle.operation) {
|
||
auto word_address = cycle.word_address();
|
||
|
||
// Everything above E0 0000 is signalled as being on the peripheral bus.
|
||
mc68000_.set_is_peripheral_address(word_address >= 0x700000);
|
||
|
||
if(word_address >= 0x400000) {
|
||
if(cycle.data_select_active()) {
|
||
const int register_address = word_address >> 8;
|
||
|
||
switch(word_address & 0x78f000) {
|
||
case 0x70f000:
|
||
// VIA accesses are via address 0xefe1fe + register*512,
|
||
// which at word precision is 0x77f0ff + register*256.
|
||
if(cycle.operation & Microcycle::Read) {
|
||
cycle.value->halves.low = via_.get_register(register_address);
|
||
} else {
|
||
via_.set_register(register_address, cycle.value->halves.low);
|
||
}
|
||
break;
|
||
|
||
case 0x68f000:
|
||
// The IWM; this is a purely polled device, so can be run on demand.
|
||
#ifndef NDEBUG
|
||
// printf("[%06x]: ", mc68000_.get_state().program_counter);
|
||
#endif
|
||
iwm_.flush();
|
||
if(cycle.operation & Microcycle::Read) {
|
||
cycle.value->halves.low = iwm_.iwm.read(register_address);
|
||
} else {
|
||
iwm_.iwm.write(register_address, cycle.value->halves.low);
|
||
}
|
||
break;
|
||
|
||
case 0x780000:
|
||
// Phase read.
|
||
if(cycle.operation & Microcycle::Read) {
|
||
cycle.value->halves.low = phase_ & 7;
|
||
}
|
||
break;
|
||
|
||
case 0x480000: case 0x48f000:
|
||
case 0x580000: case 0x58f000:
|
||
// Any word access here adjusts phase.
|
||
if(cycle.operation & Microcycle::SelectWord) {
|
||
++phase_;
|
||
} else {
|
||
if(word_address < 0x500000) {
|
||
// A0 = 1 => reset; A0 = 0 => read.
|
||
if(*cycle.address & 1) {
|
||
scc_.reset();
|
||
} else {
|
||
const auto read = scc_.read(int(word_address));
|
||
if(cycle.operation & Microcycle::Read) {
|
||
cycle.value->halves.low = read;
|
||
}
|
||
}
|
||
} else {
|
||
if(*cycle.address & 1) {
|
||
if(cycle.operation & Microcycle::Read) {
|
||
scc_.write(int(word_address), 0xff);
|
||
} else {
|
||
scc_.write(int(word_address), cycle.value->halves.low);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
break;
|
||
|
||
default:
|
||
if(cycle.operation & Microcycle::Read) {
|
||
printf("Unrecognised read %06x\n", *cycle.address & 0xffffff);
|
||
cycle.value->halves.low = 0x00;
|
||
} else {
|
||
printf("Unrecognised write %06x\n", *cycle.address & 0xffffff);
|
||
}
|
||
break;
|
||
}
|
||
if(cycle.operation & Microcycle::SelectWord) cycle.value->halves.high = 0xff;
|
||
}
|
||
} else {
|
||
if(cycle.data_select_active()) {
|
||
uint16_t *memory_base = nullptr;
|
||
auto operation = cycle.operation;
|
||
|
||
// When ROM overlay is enabled, the ROM begins at both $000000 and $400000,
|
||
// and RAM is available at $600000.
|
||
//
|
||
// Otherwise RAM is mapped at $000000 and ROM from $400000.
|
||
if(
|
||
(ROM_is_overlay_ && word_address >= 0x300000) ||
|
||
(!ROM_is_overlay_ && word_address < 0x200000)
|
||
) {
|
||
memory_base = ram_;
|
||
word_address &= ram_mask_;
|
||
} else {
|
||
memory_base = rom_;
|
||
word_address &= rom_mask_;
|
||
|
||
// Disallow writes to ROM; also it doesn't mirror above 0x60000, ever.
|
||
if(!(operation & Microcycle::Read) || word_address >= 0x300000) operation = 0;
|
||
}
|
||
|
||
const auto masked_operation = operation & (Microcycle::SelectWord | Microcycle::SelectByte | Microcycle::Read | Microcycle::InterruptAcknowledge);
|
||
switch(masked_operation) {
|
||
default:
|
||
break;
|
||
|
||
// Catches the deliberation set of operation to 0 above.
|
||
case 0: break;
|
||
|
||
case Microcycle::InterruptAcknowledge | Microcycle::SelectByte:
|
||
// The Macintosh uses autovectored interrupts.
|
||
mc68000_.set_is_peripheral_address(true);
|
||
break;
|
||
|
||
case Microcycle::SelectWord | Microcycle::Read:
|
||
cycle.value->full = memory_base[word_address];
|
||
break;
|
||
case Microcycle::SelectByte | Microcycle::Read:
|
||
cycle.value->halves.low = uint8_t(memory_base[word_address] >> cycle.byte_shift());
|
||
break;
|
||
case Microcycle::SelectWord:
|
||
memory_base[word_address] = cycle.value->full;
|
||
break;
|
||
case Microcycle::SelectByte:
|
||
memory_base[word_address] = uint16_t(
|
||
(cycle.value->halves.low << cycle.byte_shift()) |
|
||
(memory_base[word_address] & cycle.untouched_byte_mask())
|
||
);
|
||
break;
|
||
}
|
||
|
||
// if(!(operation & Microcycle::Read) && (word_address == (0x00000172 >> 1))) {
|
||
// if(operation & Microcycle::SelectByte)
|
||
// printf("MBState: %02x\n", cycle.value->halves.low);
|
||
// else
|
||
// printf("MBState: %04x\n", cycle.value->full);
|
||
// }
|
||
// if(
|
||
// (
|
||
// (word_address == (0x00000352 >> 1))
|
||
// || (word_address == (0x00000354 >> 1))
|
||
// || (word_address == (0x00005d16 >> 1))
|
||
// )
|
||
// ) {
|
||
// printf("%s %08x: %04x from around %08x\n", (operation & Microcycle::Read) ? "Read" : "Write", word_address << 1, memory_base[word_address], mc68000_.get_state().program_counter);
|
||
// }
|
||
} else {
|
||
// TODO: add delay if this is a RAM access and video blocks it momentarily.
|
||
// "Each [video] fetch took two cycles out of eight"
|
||
}
|
||
}
|
||
}
|
||
|
||
/*
|
||
Normal memory map:
|
||
|
||
000000: RAM
|
||
400000: ROM
|
||
9FFFF8+: SCC read operations
|
||
BFFFF8+: SCC write operations
|
||
DFE1FF+: IWM
|
||
EFE1FE+: VIA
|
||
*/
|
||
|
||
return HalfCycles(0);
|
||
}
|
||
|
||
void flush() {
|
||
// Flush the video before the audio queue; in a Mac the
|
||
// video is responsible for providing part of the
|
||
// audio signal, so the two aren't as distinct as in
|
||
// most machines.
|
||
// video_.run_for(time_since_video_update_.flush());
|
||
|
||
// As above: flush audio after video.
|
||
via_.flush();
|
||
audio_.queue.perform();
|
||
}
|
||
|
||
void set_rom_is_overlay(bool rom_is_overlay) {
|
||
ROM_is_overlay_ = rom_is_overlay;
|
||
}
|
||
|
||
void set_use_alternate_buffers(bool use_alternate_screen_buffer, bool use_alternate_audio_buffer) {
|
||
video_.set_use_alternate_buffers(use_alternate_screen_buffer, use_alternate_audio_buffer);
|
||
}
|
||
|
||
bool insert_media(const Analyser::Static::Media &media) override {
|
||
if(media.disks.empty())
|
||
return false;
|
||
|
||
// TODO: shouldn't allow disks to be replaced like this, as the Mac
|
||
// uses software eject. Will need to expand messaging ability of
|
||
// insert_media.
|
||
drives_[0].set_disk(media.disks[0]);
|
||
|
||
return true;
|
||
}
|
||
|
||
// MARK: Keyboard input.
|
||
|
||
KeyboardMapper *get_keyboard_mapper() override {
|
||
return &keyboard_mapper_;
|
||
}
|
||
|
||
void set_key_state(uint16_t key, bool is_pressed) override {
|
||
keyboard_.enqueue_key_state(key, is_pressed);
|
||
}
|
||
|
||
// TODO: clear all keys.
|
||
|
||
private:
|
||
Inputs::Mouse &get_mouse() override {
|
||
return mouse_;
|
||
}
|
||
|
||
struct IWM {
|
||
IWM(int clock_rate) : iwm(clock_rate) {}
|
||
|
||
Apple::IWM iwm;
|
||
HalfCycles time_since_update;
|
||
|
||
void flush() {
|
||
iwm.run_for(time_since_update.flush_cycles());
|
||
}
|
||
};
|
||
|
||
class VIAPortHandler: public MOS::MOS6522::PortHandler {
|
||
public:
|
||
VIAPortHandler(ConcreteMachine &machine, RealTimeClock &clock, Keyboard &keyboard, Video &video, DeferredAudio &audio, IWM &iwm, Inputs::QuadratureMouse &mouse) :
|
||
machine_(machine), clock_(clock), keyboard_(keyboard), video_(video), audio_(audio), iwm_(iwm), mouse_(mouse) {}
|
||
|
||
using Port = MOS::MOS6522::Port;
|
||
using Line = MOS::MOS6522::Line;
|
||
|
||
void set_port_output(Port port, uint8_t value, uint8_t direction_mask) {
|
||
/*
|
||
Peripheral lines: keyboard data, interrupt configuration.
|
||
(See p176 [/215])
|
||
*/
|
||
switch(port) {
|
||
case Port::A:
|
||
/*
|
||
Port A:
|
||
b7: [input] SCC wait/request (/W/REQA and /W/REQB wired together for a logical OR)
|
||
b6: 0 = alternate screen buffer, 1 = main screen buffer
|
||
b5: floppy disk SEL state control (upper/lower head "among other things")
|
||
b4: 1 = use ROM overlay memory map, 0 = use ordinary memory map
|
||
b3: 0 = use alternate sound buffer, 1 = use ordinary sound buffer
|
||
b2–b0: audio output volume
|
||
*/
|
||
iwm_.flush();
|
||
iwm_.iwm.set_select(!!(value & 0x20));
|
||
|
||
machine_.set_use_alternate_buffers(!(value & 0x40), !(value&0x08));
|
||
machine_.set_rom_is_overlay(!!(value & 0x10));
|
||
|
||
audio_.flush();
|
||
audio_.audio.set_volume(value & 7);
|
||
break;
|
||
|
||
case Port::B:
|
||
/*
|
||
Port B:
|
||
b7: 0 = sound enabled, 1 = sound disabled
|
||
b6: [input] 0 = video beam in visible portion of line, 1 = outside
|
||
b5: [input] mouse y2
|
||
b4: [input] mouse x2
|
||
b3: [input] 0 = mouse button down, 1 = up
|
||
b2: 0 = real-time clock enabled, 1 = disabled
|
||
b1: clock's data-clock line
|
||
b0: clock's serial data line
|
||
*/
|
||
if(value & 0x4) clock_.abort();
|
||
else clock_.set_input(!!(value & 0x2), !!(value & 0x1));
|
||
|
||
audio_.flush();
|
||
audio_.audio.set_enabled(!(value & 0x80));
|
||
break;
|
||
}
|
||
}
|
||
|
||
uint8_t get_port_input(Port port) {
|
||
switch(port) {
|
||
case Port::A:
|
||
// printf("6522 r A\n");
|
||
return 0x00; // TODO: b7 = SCC wait/request
|
||
|
||
case Port::B:
|
||
return uint8_t(
|
||
((mouse_.get_button_mask() & 1) ? 0x00 : 0x08) |
|
||
((mouse_.get_channel(0) & 2) << 3) |
|
||
((mouse_.get_channel(1) & 2) << 4) |
|
||
(clock_.get_data() ? 0x02 : 0x00) |
|
||
(video_.is_outputting() ? 0x00 : 0x40)
|
||
);
|
||
}
|
||
}
|
||
|
||
void set_control_line_output(Port port, Line line, bool value) {
|
||
/*
|
||
Keyboard wiring (I believe):
|
||
CB2 = data (input/output)
|
||
CB1 = clock (input)
|
||
|
||
CA2 is used for receiving RTC interrupts.
|
||
CA1 is used for receiving vsync.
|
||
*/
|
||
if(port == Port::B && line == Line::Two) keyboard_.set_input(value);
|
||
else printf("Unhandled control line output: %c %d\n", port ? 'B' : 'A', int(line));
|
||
}
|
||
|
||
void run_for(HalfCycles duration) {
|
||
audio_.time_since_update += duration;
|
||
}
|
||
|
||
void flush() {
|
||
audio_.flush();
|
||
}
|
||
|
||
private:
|
||
ConcreteMachine &machine_;
|
||
RealTimeClock &clock_;
|
||
Keyboard &keyboard_;
|
||
Video &video_;
|
||
DeferredAudio &audio_;
|
||
IWM &iwm_;
|
||
Inputs::QuadratureMouse &mouse_;
|
||
};
|
||
|
||
CPU::MC68000::Processor<ConcreteMachine, true> mc68000_;
|
||
|
||
DriveSpeedAccumulator drive_speed_accumulator_;
|
||
IWM iwm_;
|
||
|
||
DeferredAudio audio_;
|
||
Video video_;
|
||
|
||
RealTimeClock clock_;
|
||
Keyboard keyboard_;
|
||
|
||
MOS::MOS6522::MOS6522<VIAPortHandler> via_;
|
||
VIAPortHandler via_port_handler_;
|
||
|
||
Zilog::SCC::z8530 scc_;
|
||
|
||
HalfCycles via_clock_;
|
||
HalfCycles real_time_clock_;
|
||
HalfCycles keyboard_clock_;
|
||
HalfCycles video_clock_;
|
||
// HalfCycles time_since_video_update_;
|
||
HalfCycles time_since_iwm_update_;
|
||
HalfCycles time_since_mouse_update_;
|
||
|
||
bool ROM_is_overlay_ = true;
|
||
int phase_ = 1;
|
||
|
||
SonyDrive drives_[2];
|
||
Inputs::QuadratureMouse mouse_;
|
||
|
||
Apple::Macintosh::KeyboardMapper keyboard_mapper_;
|
||
|
||
uint32_t ram_mask_ = 0;
|
||
uint32_t rom_mask_ = 0;
|
||
uint16_t rom_[64*1024];
|
||
uint16_t ram_[256*1024];
|
||
};
|
||
|
||
}
|
||
}
|
||
|
||
using namespace Apple::Macintosh;
|
||
|
||
Machine *Machine::Macintosh(const Analyser::Static::Target *target, const ROMMachine::ROMFetcher &rom_fetcher) {
|
||
auto *const mac_target = dynamic_cast<const Analyser::Static::Macintosh::Target *>(target);
|
||
|
||
using Model = Analyser::Static::Macintosh::Target::Model;
|
||
switch(mac_target->model) {
|
||
default:
|
||
case Model::Mac128k: return new ConcreteMachine<Model::Mac128k>(*mac_target, rom_fetcher);
|
||
case Model::Mac512k: return new ConcreteMachine<Model::Mac512k>(*mac_target, rom_fetcher);
|
||
case Model::Mac512ke: return new ConcreteMachine<Model::Mac512ke>(*mac_target, rom_fetcher);
|
||
case Model::MacPlus: return new ConcreteMachine<Model::MacPlus>(*mac_target, rom_fetcher);
|
||
}
|
||
}
|
||
|
||
Machine::~Machine() {}
|