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CLK/Machines/AtariST/AtariST.cpp
Thomas Harte d44734d105 Attempts a fuller setting of GPIP inputs.
2019-10-27 22:39:21 -04:00

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//
// AtariST.cpp
// Clock Signal
//
// Created by Thomas Harte on 03/10/2019.
// Copyright © 2019 Thomas Harte. All rights reserved.
//
#include "AtariST.hpp"
#include "../CRTMachine.hpp"
//#define LOG_TRACE
#include "../../Processors/68000/68000.hpp"
#include "../../Components/AY38910/AY38910.hpp"
#include "../../Components/68901/MFP68901.hpp"
#include "../../Components/6850/6850.hpp"
#include "DMAController.hpp"
#include "Video.hpp"
#include "../../ClockReceiver/JustInTime.hpp"
#include "../../ClockReceiver/ForceInline.hpp"
#include "../../Outputs/Speaker/Implementation/LowpassSpeaker.hpp"
#include "../../Outputs/Log.hpp"
#include "../Utility/MemoryPacker.hpp"
#include "../Utility/MemoryFuzzer.hpp"
namespace Atari {
namespace ST {
const int CLOCK_RATE = 8000000;
/*!
A receiver for the Atari ST's "intelligent keyboard" commands, which actually cover
keyboard input and output and mouse handling.
*/
class IntelligentKeyboard:
public Serial::Line::ReadDelegate,
public ClockingHint::Source {
public:
IntelligentKeyboard(Serial::Line &input, Serial::Line &output) : output_line_(output) {
input.set_read_delegate(this, Storage::Time(2, 15625));
output_line_.set_writer_clock_rate(15625);
}
bool serial_line_did_produce_bit(Serial::Line *, int bit) final {
command_ = (command_ >> 1) | (bit << 9);
bit_count_ = (bit_count_ + 1) % 10;
if(!bit_count_) {
dispatch_command(uint8_t(command_ >> 1));
command_ = 0;
return false;
}
return true;
}
ClockingHint::Preference preferred_clocking() final {
return output_line_.transmission_data_time_remaining() ? ClockingHint::Preference::RealTime : ClockingHint::Preference::None;
}
void run_for(HalfCycles duration) {
output_line_.advance_writer(duration.as_int());
}
private:
// MARK: - Serial line state.
int bit_count_ = 0;
int command_ = 0;
Serial::Line &output_line_;
void output_byte(uint8_t value) {
// Wrap the value in a start and stop bit, and send it on its way.
output_line_.write(2, 10, 0x200 | (value << 1));
update_clocking_observer();
}
// MARK: - Command dispatch.
std::vector<uint8_t> command_sequence_;
void dispatch_command(uint8_t command) {
// Enqueue for parsing.
command_sequence_.push_back(command);
// For each possible command, check that the proper number of bytes are present.
// If not, exit. If so, perform and drop out of the switch.
switch(command_sequence_.front()) {
default:
printf("Unrecognised IKBD command %02x\n", command);
break;
case 0x80:
/*
Reset: 0x80 0x01.
"Any byte following an 0x80 command byte other than 0x01 is ignored (and causes the 0x80 to be ignored)."
*/
if(command_sequence_.size() != 2) return;
if(command_sequence_[1] == 0x01) {
reset();
}
break;
case 0x07:
if(command_sequence_.size() != 2) return;
set_mouse_button_actions(command_sequence_[1]);
break;
case 0x08:
set_relative_mouse_position_reporting();
break;
case 0x09:
if(command_sequence_.size() != 5) return;
set_absolute_mouse_position_reporting(
uint16_t((command_sequence_[1] << 8) | command_sequence_[2]),
uint16_t((command_sequence_[3] << 8) | command_sequence_[4])
);
break;
case 0x0a:
if(command_sequence_.size() != 3) return;
set_mouse_keycode_reporting(command_sequence_[1], command_sequence_[2]);
break;
case 0x0b:
if(command_sequence_.size() != 3) return;
set_mouse_threshold(command_sequence_[1], command_sequence_[2]);
break;
case 0x0c:
if(command_sequence_.size() != 3) return;
set_mouse_scale(command_sequence_[1], command_sequence_[2]);
break;
case 0x0d:
interrogate_mouse_position();
break;
case 0x0e:
if(command_sequence_.size() != 6) return;
/* command_sequence_[1] has no defined meaning. */
set_mouse_position(
uint16_t((command_sequence_[2] << 8) | command_sequence_[3]),
uint16_t((command_sequence_[4] << 8) | command_sequence_[5])
);
break;
case 0x0f: set_mouse_y_upward(); break;
case 0x10: set_mouse_y_downward(); break;
case 0x11: resume(); break;
case 0x12: disable_mouse(); break;
case 0x13: pause(); break;
case 0x1a: disable_joysticks(); break;
}
// There was no premature exit, so a complete command sequence must have been satisfied.
command_sequence_.clear();
}
// MARK: - Flow control.
void reset() {
// Reset should perform a self test, lasting at most 200ms, then post 0xf0.
// Following that it should look for any keys that currently seem to be pressed.
// Those are considered stuck and a break code is generated for them.
output_byte(0xf0);
}
void resume() {
}
void pause() {
}
// MARK: - Mouse commands.
void disable_mouse() {
}
void set_relative_mouse_position_reporting() {
}
void set_absolute_mouse_position_reporting(uint16_t max_x, uint16_t max_y) {
}
void set_mouse_position(uint16_t x, uint16_t y) {
}
void set_mouse_keycode_reporting(uint8_t delta_x, uint8_t delta_y) {
}
void set_mouse_threshold(uint8_t x, uint8_t y) {
}
void set_mouse_scale(uint8_t x, uint8_t y) {
}
void set_mouse_y_downward() {
}
void set_mouse_y_upward() {
}
void set_mouse_button_actions(uint8_t actions) {
}
void interrogate_mouse_position() {
output_byte(0xf7); // Beginning of mouse response.
output_byte(0x00); // 0000dcba; a = right button down since last interrogation, b = right button up since, c/d = left button.
output_byte(0x00); // x motion: MSB, LSB
output_byte(0x00);
output_byte(0x00); // y motion: MSB, LSB
output_byte(0x00);
}
// MARK: - Joystick commands.
void disable_joysticks() {
}
};
using Target = Analyser::Static::Target;
class ConcreteMachine:
public Atari::ST::Machine,
public CPU::MC68000::BusHandler,
public CRTMachine::Machine,
public ClockingHint::Observer,
public Motorola::ACIA::ACIA::InterruptDelegate,
public Motorola::MFP68901::MFP68901::InterruptDelegate {
public:
ConcreteMachine(const Target &target, const ROMMachine::ROMFetcher &rom_fetcher) :
mc68000_(*this),
keyboard_acia_(Cycles(500000)),
midi_acia_(Cycles(500000)),
ay_(audio_queue_),
speaker_(ay_),
ikbd_(keyboard_acia_->transmit, keyboard_acia_->receive) {
set_clock_rate(CLOCK_RATE);
speaker_.set_input_rate(CLOCK_RATE / 4);
ram_.resize(512 * 512);
video_->set_ram(ram_.data());
Memory::Fuzz(ram_);
std::vector<ROMMachine::ROM> rom_descriptions = {
{"AtariST", "the TOS ROM", "tos100.img", 192*1024, 0x1a586c64}
};
const auto roms = rom_fetcher(rom_descriptions);
if(!roms[0]) {
throw ROMMachine::Error::MissingROMs;
}
Memory::PackBigEndian16(*roms[0], rom_);
// Set up basic memory map.
memory_map_[0] = BusDevice::MostlyRAM;
int c = 1;
for(; c < 0x08; ++c) memory_map_[c] = BusDevice::RAM;
for(; c < 0xff; ++c) memory_map_[c] = BusDevice::Unassigned;
const bool is_early_tos = true;
if(is_early_tos) {
for(c = 0xfc; c < 0xff; ++c) memory_map_[c] = BusDevice::ROM;
} else {
for(c = 0xe0; c < 0xe4; ++c) memory_map_[c] = BusDevice::ROM;
}
memory_map_[0xfa] = memory_map_[0xfb] = BusDevice::Cartridge;
memory_map_[0xff] = BusDevice::IO;
midi_acia_->set_interrupt_delegate(this);
keyboard_acia_->set_interrupt_delegate(this);
midi_acia_->set_clocking_hint_observer(this);
keyboard_acia_->set_clocking_hint_observer(this);
ikbd_.set_clocking_hint_observer(this);
mfp_->set_interrupt_delegate(this);
set_gpip_input();
}
~ConcreteMachine() {
audio_queue_.flush();
}
// MARK: CRTMachine::Machine
void set_scan_target(Outputs::Display::ScanTarget *scan_target) final {
video_->set_scan_target(scan_target);
}
Outputs::Speaker::Speaker *get_speaker() final {
return &speaker_;
}
void run_for(const Cycles cycles) final {
mc68000_.run_for(cycles);
}
// MARK: MC68000::BusHandler
using Microcycle = CPU::MC68000::Microcycle;
HalfCycles perform_bus_operation(const CPU::MC68000::Microcycle &cycle, int is_supervisor) {
// Advance time.
advance_time(cycle.length);
// A null cycle leaves nothing else to do.
if(!(cycle.operation & (Microcycle::NewAddress | Microcycle::SameAddress))) return HalfCycles(0);
/* TODO: DTack, bus error, VPA. */
// An interrupt acknowledge, perhaps?
if(cycle.operation & Microcycle::InterruptAcknowledge) {
// Current implementation: everything other than 6 (i.e. the MFP is autovectored.
if((cycle.word_address()&7) != 6) {
mc68000_.set_is_peripheral_address(true);
return HalfCycles(0);
} else {
if(cycle.operation & Microcycle::SelectByte) {
cycle.value->halves.low = mfp_->acknowledge_interrupt();
}
return HalfCycles(0);
}
}
// Just in case the last cycle was an interrupt acknowledge. TODO: find a better solution?
mc68000_.set_is_peripheral_address(false);
auto address = cycle.word_address();
// if(cycle.data_select_active()) printf("%c %06x\n", (cycle.operation & Microcycle::Read) ? 'r' : 'w', *cycle.address & 0xffffff);
uint16_t *memory;
switch(memory_map_[address >> 15]) {
case BusDevice::MostlyRAM:
if(address < 4) {
memory = rom_.data();
break;
}
case BusDevice::RAM:
memory = ram_.data();
address &= ram_.size() - 1;
// TODO: align with the next access window.
break;
case BusDevice::ROM:
memory = rom_.data();
address %= rom_.size();
break;
case BusDevice::Unassigned:
// TODO: figure out the rules about bus errors.
case BusDevice::Cartridge:
/*
TOS 1.0 appears to attempt to read from the catridge before it has setup
the bus error vector. Therefore I assume no bus error flows.
*/
switch(cycle.operation & (Microcycle::SelectWord | Microcycle::SelectByte | Microcycle::Read)) {
default: break;
case Microcycle::SelectWord | Microcycle::Read:
*cycle.value = 0xffff;
break;
case Microcycle::SelectByte | Microcycle::Read:
cycle.value->halves.low = 0xff;
break;
}
return HalfCycles(0);
case BusDevice::IO:
switch(address) {
default:
// assert(false);
case 0x7fc000:
/* Memory controller configuration:
b0, b1: bank 1
b2, b3: bank 0
00 = 128k
01 = 512k
10 = 2mb
11 = reserved
*/
break;
case 0x7fc400: /* PSG: write to select register, read to read register. */
case 0x7fc401: /* PSG: write to write register. */
if(!cycle.data_select_active()) return HalfCycles(0);
// TODO: byte accesses to the odd addresses shouldn't obey logic below.
advance_time(HalfCycles(2));
update_audio();
if(cycle.operation & Microcycle::Read) {
ay_.set_control_lines(GI::AY38910::ControlLines(GI::AY38910::BC2 | GI::AY38910::BC1));
cycle.value->halves.low = ay_.get_data_output();
ay_.set_control_lines(GI::AY38910::ControlLines(0));
} else {
if(address == 0x7fc400) {
ay_.set_control_lines(GI::AY38910::BC1);
ay_.set_data_input(cycle.value->halves.low);
ay_.set_control_lines(GI::AY38910::ControlLines(0));
} else {
ay_.set_control_lines(GI::AY38910::ControlLines(GI::AY38910::BC2 | GI::AY38910::BDIR));
ay_.set_data_input(cycle.value->halves.low);
ay_.set_control_lines(GI::AY38910::ControlLines(0));
}
}
/*
TODO: Port A:
b7: reserved
b6: "freely usable output (monitor jack)"
b5: centronics strobe
b4: RS-232 DTR output
b3: RS-232 RTS output
b2: select floppy drive 1
b1: select floppy drive 0
b0: "page choice signal for double-sided floppy drive"
*/
return HalfCycles(2);
// The MFP block:
case 0x7ffd00: case 0x7ffd01: case 0x7ffd02: case 0x7ffd03:
case 0x7ffd04: case 0x7ffd05: case 0x7ffd06: case 0x7ffd07:
case 0x7ffd08: case 0x7ffd09: case 0x7ffd0a: case 0x7ffd0b:
case 0x7ffd0c: case 0x7ffd0d: case 0x7ffd0e: case 0x7ffd0f:
case 0x7ffd10: case 0x7ffd11: case 0x7ffd12: case 0x7ffd13:
case 0x7ffd14: case 0x7ffd15: case 0x7ffd16: case 0x7ffd17:
case 0x7ffd18: case 0x7ffd19: case 0x7ffd1a: case 0x7ffd1b:
case 0x7ffd1c: case 0x7ffd1d: case 0x7ffd1e: case 0x7ffd1f:
if(!cycle.data_select_active()) return HalfCycles(0);
// The lower data lines aren't connected.
if(!cycle.upper_data_select()) {
if(cycle.operation & Microcycle::Read) {
cycle.value->halves.low = 0xff;
}
return HalfCycles(0);
}
if(cycle.operation & Microcycle::Read) {
const uint8_t value = mfp_->read(int(address));
if(cycle.operation & Microcycle::SelectByte) {
cycle.value->halves.low = value;
} else {
cycle.value->halves.high = value;
cycle.value->halves.low = 0xff;
}
} else {
if(cycle.operation & Microcycle::SelectByte) {
mfp_->write(int(address), cycle.value->halves.low);
} else {
mfp_->write(int(address), cycle.value->halves.high);
}
}
break;
// Video controls.
case 0x7fc100: case 0x7fc101: case 0x7fc102: case 0x7fc103:
case 0x7fc104: case 0x7fc105: case 0x7fc106: case 0x7fc107:
case 0x7fc108: case 0x7fc109: case 0x7fc10a: case 0x7fc10b:
case 0x7fc10c: case 0x7fc10d: case 0x7fc10e: case 0x7fc10f:
case 0x7fc110: case 0x7fc111: case 0x7fc112: case 0x7fc113:
case 0x7fc114: case 0x7fc115: case 0x7fc116: case 0x7fc117:
case 0x7fc118: case 0x7fc119: case 0x7fc11a: case 0x7fc11b:
case 0x7fc11c: case 0x7fc11d: case 0x7fc11e: case 0x7fc11f:
case 0x7fc120: case 0x7fc121: case 0x7fc122: case 0x7fc123:
case 0x7fc124: case 0x7fc125: case 0x7fc126: case 0x7fc127:
case 0x7fc128: case 0x7fc129: case 0x7fc12a: case 0x7fc12b:
case 0x7fc12c: case 0x7fc12d: case 0x7fc12e: case 0x7fc12f:
case 0x7fc130: case 0x7fc131:
if(!cycle.data_select_active()) return HalfCycles(0);
if(cycle.operation & Microcycle::Read) {
const uint8_t value = video_->read(int(address));
if(cycle.operation & Microcycle::SelectByte) {
cycle.value->halves.low = value;
} else {
cycle.value->halves.high = value;
cycle.value->halves.low = 0xff;
}
} else {
if(cycle.operation & Microcycle::SelectByte) {
video_->write(int(address), uint16_t(cycle.value->halves.low << cycle.byte_shift()));
} else {
video_->write(int(address), cycle.value->full);
}
}
break;
// ACIAs.
case 0x7ffe00: case 0x7ffe01: case 0x7ffe02: case 0x7ffe03: {
// Set VPA.
mc68000_.set_is_peripheral_address(!cycle.data_select_active());
if(!cycle.data_select_active()) return HalfCycles(0);
const auto acia_ = (address < 0x7ffe02) ? &keyboard_acia_ : &midi_acia_;
if(cycle.operation & Microcycle::Read) {
const uint8_t value = (*acia_)->read(int(address));
if(cycle.operation & Microcycle::SelectByte) {
cycle.value->halves.low = value;
} else {
cycle.value->halves.high = value;
cycle.value->halves.low = 0xff;
}
} else {
if(cycle.operation & Microcycle::SelectByte) {
(*acia_)->write(int(address), cycle.value->halves.low);
} else {
(*acia_)->write(int(address), cycle.value->halves.high);
}
}
} break;
// DMA.
case 0x7fc302: case 0x7fc303: case 0x7fc304: case 0x7fc305: case 0x7fc306:
if(!cycle.data_select_active()) return HalfCycles(0);
if(cycle.operation & Microcycle::Read) {
const auto value = dma_->read(int(address));
if(cycle.operation & Microcycle::SelectWord) {
cycle.value->full = value;
} else {
cycle.value->halves.low = uint8_t(value >> cycle.byte_shift());
}
} else {
if(cycle.operation & Microcycle::SelectWord) {
dma_->write(int(address), cycle.value->full);
} else {
dma_->write(int(address), uint16_t(
(cycle.value->halves.low << cycle.byte_shift()) |
(0xff00 >> cycle.byte_shift())
));
}
}
break;
}
return HalfCycles(0);
}
// If control has fallen through to here, the access is either a read from ROM, or a read or write to RAM.
switch(cycle.operation & (Microcycle::SelectWord | Microcycle::SelectByte | Microcycle::Read)) {
default:
break;
case Microcycle::SelectWord | Microcycle::Read:
cycle.value->full = memory[address];
break;
case Microcycle::SelectByte | Microcycle::Read:
cycle.value->halves.low = uint8_t(memory[address] >> cycle.byte_shift());
break;
case Microcycle::SelectWord:
memory[address] = cycle.value->full;
break;
case Microcycle::SelectByte:
memory[address] = uint16_t(
(cycle.value->halves.low << cycle.byte_shift()) |
(memory[address] & cycle.untouched_byte_mask())
);
break;
}
return HalfCycles(0);
}
void flush() {
audio_queue_.perform();
video_.flush();
}
private:
forceinline void advance_time(HalfCycles length) {
cycles_since_audio_update_ += length;
mfp_ += length;
dma_ += length;
keyboard_acia_ += length;
midi_acia_ += length;
if(!may_defer_acias_) {
keyboard_acia_.flush();
midi_acia_.flush();
}
if(keyboard_needs_clock_) {
cycles_since_ikbd_update_ += length;
ikbd_.run_for(cycles_since_ikbd_update_.divide(HalfCycles(512)));
}
while(length >= cycles_until_video_event_) {
length -= cycles_until_video_event_;
video_ += cycles_until_video_event_;
cycles_until_video_event_ = video_->get_next_sequence_point();
mfp_->set_timer_event_input(1, video_->display_enabled());
update_interrupt_input();
}
cycles_until_video_event_ -= length;
video_ += length;
}
void update_audio() {
speaker_.run_for(audio_queue_, cycles_since_audio_update_.divide_cycles(Cycles(4)));
}
CPU::MC68000::Processor<ConcreteMachine, true> mc68000_;
JustInTimeActor<Video> video_;
HalfCycles cycles_until_video_event_;
JustInTimeActor<Motorola::MFP68901::MFP68901> mfp_;
JustInTimeActor<Motorola::ACIA::ACIA, 16> keyboard_acia_;
JustInTimeActor<Motorola::ACIA::ACIA, 16> midi_acia_;
Concurrency::DeferringAsyncTaskQueue audio_queue_;
GI::AY38910::AY38910 ay_;
Outputs::Speaker::LowpassSpeaker<GI::AY38910::AY38910> speaker_;
HalfCycles cycles_since_audio_update_;
JustInTimeActor<DMAController> dma_;
HalfCycles cycles_since_ikbd_update_;
IntelligentKeyboard ikbd_;
std::vector<uint16_t> ram_;
std::vector<uint16_t> rom_;
enum class BusDevice {
MostlyRAM, RAM, ROM, Cartridge, IO, Unassigned
};
BusDevice memory_map_[256];
// MARK: - Clocking Management.
bool may_defer_acias_ = true;
bool keyboard_needs_clock_ = false;
void set_component_prefers_clocking(ClockingHint::Source *component, ClockingHint::Preference clocking) final {
// This is being called by one of the components; avoid any time flushing here as that's
// already dealt with (and, just to be absolutely sure, to avoid recursive mania).
may_defer_acias_ =
(keyboard_acia_.last_valid()->preferred_clocking() != ClockingHint::Preference::RealTime) &&
(midi_acia_.last_valid()->preferred_clocking() != ClockingHint::Preference::RealTime);
keyboard_needs_clock_ = ikbd_.preferred_clocking() != ClockingHint::Preference::None;
}
// MARK: - GPIP input.
void acia6850_did_change_interrupt_status(Motorola::ACIA::ACIA *acia) final {
set_gpip_input();
}
void set_gpip_input() {
/*
Atari ST GPIP bits:
GPIP 7: monochrome monitor detect
GPIP 6: RS-232 ring indicator
GPIP 5: FD/HD interrupt
GPIP 4: keyboard/MIDI interrupt
GPIP 3: unused
GPIP 2: RS-232 clear to send
GPIP 1: RS-232 carrier detect
GPIP 0: centronics busy
*/
mfp_->set_port_input(
0x00 | // b7: Monochrome monitor detect (1 = is monochrome).
0x40 | // b6: RS-232 ring indicator.
0x20 | // b5: FD/HS interrupt (0 = interrupt requested).
((keyboard_acia_->get_interrupt_line() || midi_acia_->get_interrupt_line()) ? 0x0 : 0x10) | // b4: Keyboard/MIDI interrupt (0 = interrupt requested).
0x08 | // b3: Unused
0x04 | // b2: RS-232 clear to send.
0x02 | // b1 : RS-232 carrier detect.
0x00 // b0: Centronics busy (1 = busy).
);
}
// MARK - MFP input.
void mfp68901_did_change_interrupt_status(Motorola::MFP68901::MFP68901 *mfp) final {
update_interrupt_input();
}
void update_interrupt_input() {
if(mfp_->get_interrupt_line()) {
mc68000_.set_interrupt_level(6);
} else if(video_->vsync()) {
mc68000_.set_interrupt_level(4);
} else if(video_->hsync()) {
mc68000_.set_interrupt_level(2);
} else {
mc68000_.set_interrupt_level(0);
}
}
};
}
}
using namespace Atari::ST;
Machine *Machine::AtariST(const Analyser::Static::Target *target, const ROMMachine::ROMFetcher &rom_fetcher) {
return new ConcreteMachine(*target, rom_fetcher);
}
Machine::~Machine() {}
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