diff --git a/Machines/Acorn/Archimedes/Archimedes.cpp b/Machines/Acorn/Archimedes/Archimedes.cpp
index 3cb706e42..348094fc7 100644
--- a/Machines/Acorn/Archimedes/Archimedes.cpp
+++ b/Machines/Acorn/Archimedes/Archimedes.cpp
@@ -8,6 +8,12 @@
#include "Archimedes.hpp"
+#include "HalfDuplexSerial.hpp"
+#include "InputOutputController.hpp"
+#include "Keyboard.hpp"
+#include "MemoryController.hpp"
+#include "Sound.hpp"
+
#include "../../AudioProducer.hpp"
#include "../../KeyboardMachine.hpp"
#include "../../MediaTarget.hpp"
@@ -28,1091 +34,10 @@ namespace {
Log::Logger<Log::Source::Archimedes> logger;
-enum class Zone {
- LogicallyMappedRAM,
- PhysicallyMappedRAM,
- IOControllers,
- LowROM,
- HighROM,
- VideoController,
- DMAAndMEMC,
- AddressTranslator,
-};
-constexpr std::array<Zone, 0x20> zones(bool is_read) {
- std::array<Zone, 0x20> zones{};
- for(size_t c = 0; c < zones.size(); c++) {
- const auto address = c << 21;
- if(address < 0x200'0000) {
- zones[c] = Zone::LogicallyMappedRAM;
- } else if(address < 0x300'0000) {
- zones[c] = Zone::PhysicallyMappedRAM;
- } else if(address < 0x340'0000) {
- zones[c] = Zone::IOControllers;
- } else if(address < 0x360'0000) {
- zones[c] = is_read ? Zone::LowROM : Zone::VideoController;
- } else if(address < 0x380'0000) {
- zones[c] = is_read ? Zone::LowROM : Zone::DMAAndMEMC;
- } else {
- zones[c] = is_read ? Zone::HighROM : Zone::AddressTranslator;
- }
- }
- return zones;
-}
-
-template <int start, int end> struct BitMask {
- static_assert(start >= end);
- static constexpr uint32_t value = ((1 << (start + 1)) - 1) - ((1 << end) - 1);
-};
-static_assert(BitMask<0, 0>::value == 1);
-static_assert(BitMask<1, 1>::value == 2);
-static_assert(BitMask<15, 15>::value == 32768);
-static_assert(BitMask<15, 0>::value == 0xffff);
-static_assert(BitMask<15, 14>::value == 49152);
-
}
namespace Archimedes {
-struct CMOSRAM: public I2C::Peripheral {
-
-};
-
-/// Models a half-duplex serial link between two parties, framing bytes with one start bit and two stop bits.
-struct HalfDuplexSerial {
- static constexpr uint16_t ShiftMask = 0b1111'1110'0000'0000;
-
- /// Enqueues @c value for output.
- void output(int party, uint8_t value) {
- parties_[party].output_count = 11;
- parties_[party].input = 0x7ff;
- parties_[party].output = uint16_t((value << 1) | ShiftMask);
- }
-
- /// @returns The last observed input.
- uint8_t input(int party) const {
- return uint8_t(parties_[party].input >> 1);
- }
-
- static constexpr uint8_t Receive = 1 << 0;
- static constexpr uint8_t Transmit = 1 << 1;
-
- /// @returns A bitmask of events that occurred during the last shift.
- uint8_t events(int party) {
- const auto result = parties_[party].events;
- parties_[party].events = 0;
- return result;
- }
-
- bool is_outputting(int party) const {
- return parties_[party].output_count != 11;
- }
-
- /// Updates the shifters on both sides of the serial link.
- void shift() {
- const uint16_t next = parties_[0].output & parties_[1].output & 1;
-
- for(int c = 0; c < 2; c++) {
- if(parties_[c].output_count) {
- --parties_[c].output_count;
- if(!parties_[c].output_count) {
- parties_[c].events |= Transmit;
- parties_[c].input_count = -1;
- }
- parties_[c].output = (parties_[c].output >> 1) | ShiftMask;
- } else {
- // Check for a start bit.
- if(parties_[c].input_count == -1 && !next) {
- parties_[c].input_count = 0;
- }
-
- // Shift in if currently observing.
- if(parties_[c].input_count >= 0 && parties_[c].input_count < 11) {
- parties_[c].input = uint16_t((parties_[c].input >> 1) | (next << 10));
-
- ++parties_[c].input_count;
- if(parties_[c].input_count == 11) {
- parties_[c].events |= Receive;
- parties_[c].input_count = -1;
- }
- }
- }
- }
- }
-
-private:
- struct Party {
- int output_count = 0;
- int input_count = -1;
- uint16_t output = 0xffff;
- uint16_t input = 0;
- uint8_t events = 0;
- } parties_[2];
-};
-
-static constexpr int IOCParty = 0;
-static constexpr int KeyboardParty = 1;
-
-// Resource for the keyboard protocol: https://github.com/tmk/tmk_keyboard/wiki/ACORN-ARCHIMEDES-Keyboard
-struct Keyboard {
- Keyboard(HalfDuplexSerial &serial) : serial_(serial) {}
-
- void update() {
- if(serial_.events(KeyboardParty) & HalfDuplexSerial::Receive) {
- const uint8_t input = serial_.input(KeyboardParty);
- switch(input) {
- case HRST:
- // TODO:
- case RAK1:
- case RAK2:
- serial_.output(KeyboardParty, input);
- break;
-
- case RQID:
- serial_.output(KeyboardParty, 0x81); // TODO: what keyboard type?
- break;
-
- default:
- printf("Keyboard declines to respond to %02x\n", input);
- break;
- }
- }
- }
-
-private:
- HalfDuplexSerial &serial_;
-
- static constexpr uint8_t HRST = 0b1111'1111; // Keyboard reset.
- static constexpr uint8_t RAK1 = 0b1111'1110; // Reset response #1.
- static constexpr uint8_t RAK2 = 0b1111'1101; // Reset response #2.
-
- static constexpr uint8_t RQID = 0b0010'0000; // Request for keyboard ID.
- static constexpr uint8_t RQMP = 0b0010'0010; // Request for mouse data.
-
- static constexpr uint8_t BACK = 0b0011'1111; // Acknowledge for first keyboard data byte pair.
- static constexpr uint8_t NACK = 0b0011'0000; // Acknowledge for last keyboard data byte pair, selects scan/mouse mode.
- static constexpr uint8_t SACK = 0b0011'0001; // Last data byte acknowledge.
- static constexpr uint8_t MACK = 0b0011'0010; // Last data byte acknowledge.
- static constexpr uint8_t SMAK = 0b0011'0011; // Last data byte acknowledge.
- static constexpr uint8_t PRST = 0b0010'0001; // Does nothing.
-};
-
-struct Audio {
- void set_next_end(uint32_t value) {
- next_.end = value;
- }
-
- void set_next_start(uint32_t value) {
- next_.start = value;
- next_buffer_valid_ = true;
- }
-
- bool interrupt() const {
- return !next_buffer_valid_;
- }
-
- void swap() {
- current_.start = next_.start;
- std::swap(current_.end, next_.end);
- next_buffer_valid_ = false;
- halted_ = false;
- }
-
- bool tick() {
- if(halted_) {
- return false;
- }
-
- current_.start += 16;
- if(current_.start == current_.end) {
- if(next_buffer_valid_) {
- swap();
- return true;
- } else {
- halted_ = true;
- return false;
- }
- }
- return false;
- }
-
-private:
- bool next_buffer_valid_ = false;
- bool halted_ = true; // This is a bit of a guess.
-
- struct Buffer {
- uint32_t start = 0, end = 0;
- };
- Buffer current_, next_;
-};
-struct Video {
- void write(uint32_t value) {
- const auto target = (value >> 24) & 0xfc;
-
- switch(target) {
- case 0x00: case 0x04: case 0x08: case 0x0c:
- case 0x10: case 0x14: case 0x18: case 0x1c:
- case 0x20: case 0x24: case 0x28: case 0x2c:
- case 0x30: case 0x34: case 0x38: case 0x3c:
- logger.error().append("TODO: Video palette logical colour %d to %03x", (target >> 2), value & 0x1fff);
- break;
-
- case 0x40:
- logger.error().append("TODO: Video border colour to %03x", value & 0x1fff);
- break;
-
- case 0x44: case 0x48: case 0x4c:
- logger.error().append("TODO: Cursor colour %d to %03x", (target - 0x44) >> 2, value & 0x1fff);
- break;
-
- case 0x60: case 0x64: case 0x68: case 0x6c:
- case 0x70: case 0x74: case 0x78: case 0x7c:
- logger.error().append("TODO: Stereo image register %d to %03x", (target - 0x60) >> 2, value & 0x7);
- break;
-
- case 0x80:
- logger.error().append("TODO: Video horizontal period: %d", (value >> 14) & 0x3ff);
- break;
- case 0x84:
- logger.error().append("TODO: Video horizontal sync width: %d", (value >> 14) & 0x3ff);
- break;
- case 0x88:
- logger.error().append("TODO: Video horizontal border start: %d", (value >> 14) & 0x3ff);
- break;
- case 0x8c:
- logger.error().append("TODO: Video horizontal display start: %d", (value >> 14) & 0x3ff);
- break;
- case 0x90:
- logger.error().append("TODO: Video horizontal display end: %d", (value >> 14) & 0x3ff);
- break;
- case 0x94:
- logger.error().append("TODO: Video horizontal border end: %d", (value >> 14) & 0x3ff);
- break;
- case 0x98:
- logger.error().append("TODO: Video horizontal cursor end: %d", (value >> 14) & 0x3ff);
- break;
- case 0x9c:
- logger.error().append("TODO: Video horizontal interlace: %d", (value >> 14) & 0x3ff);
- break;
-
- case 0xa0:
- logger.error().append("TODO: Video vertical period: %d", (value >> 14) & 0x3ff);
- break;
- case 0xa4:
- logger.error().append("TODO: Video vertical sync width: %d", (value >> 14) & 0x3ff);
- break;
- case 0xa8:
- logger.error().append("TODO: Video vertical border start: %d", (value >> 14) & 0x3ff);
- break;
- case 0xac:
- logger.error().append("TODO: Video vertical display start: %d", (value >> 14) & 0x3ff);
- break;
- case 0xb0:
- logger.error().append("TODO: Video vertical display end: %d", (value >> 14) & 0x3ff);
- break;
- case 0xb4:
- logger.error().append("TODO: Video vertical border end: %d", (value >> 14) & 0x3ff);
- break;
- case 0xb8:
- logger.error().append("TODO: Video vertical cursor start: %d", (value >> 14) & 0x3ff);
- break;
- case 0xbc:
- logger.error().append("TODO: Video vertical cursor end: %d", (value >> 14) & 0x3ff);
- break;
-
- case 0xc0:
- logger.error().append("TODO: Sound frequency: %d", value & 0x7f);
- break;
-
- case 0xe0:
- logger.error().append("TODO: video control: %08x", value);
- break;
-
- default:
- logger.error().append("TODO: unrecognised VIDC write of %08x", value);
- break;
- }
- }
-};
-
-// IRQ A flags
-namespace IRQA {
- // The first four of these are taken from the A500 documentation and may be inaccurate.
- static constexpr uint8_t PrinterBusy = 0x01;
- static constexpr uint8_t SerialRinging = 0x02;
- static constexpr uint8_t PrinterAcknowledge = 0x04;
- static constexpr uint8_t VerticalFlyback = 0x08;
- static constexpr uint8_t PowerOnReset = 0x10;
- static constexpr uint8_t Timer0 = 0x20;
- static constexpr uint8_t Timer1 = 0x40;
- static constexpr uint8_t SetAlways = 0x80;
-}
-
-// IRQ B flags
-namespace IRQB {
- // These are taken from the A3010 documentation.
- static constexpr uint8_t PoduleFIQRequest = 0x01;
- static constexpr uint8_t SoundBufferPointerUsed = 0x02;
- static constexpr uint8_t SerialLine = 0x04;
- static constexpr uint8_t IDE = 0x08;
- static constexpr uint8_t FloppyDiscInterrupt = 0x10;
- static constexpr uint8_t PoduleIRQRequest = 0x20;
- static constexpr uint8_t KeyboardTransmitEmpty = 0x40;
- static constexpr uint8_t KeyboardReceiveFull = 0x80;
-}
-
-// FIQ flags
-namespace FIQ {
- // These are taken from the A3010 documentation.
- static constexpr uint8_t FloppyDiscData = 0x01;
- static constexpr uint8_t SerialLine = 0x10;
- static constexpr uint8_t PoduleFIQRequest = 0x40;
- static constexpr uint8_t SetAlways = 0x80;
-}
-
-namespace InterruptRequests {
- static constexpr int IRQ = 0x01;
- static constexpr int FIQ = 0x02;
-};
-
-struct InputOutput {
- int interrupt_mask() const {
- return
- ((irq_a_.request() | irq_b_.request()) ? InterruptRequests::IRQ : 0) |
- (fiq_.request() ? InterruptRequests::FIQ : 0);
- }
-
- template <int c>
- bool tick_timer() {
- if(!counters_[c].value && !counters_[c].reload) {
- return false;
- }
-
- --counters_[c].value;
- if(!counters_[c].value) {
- counters_[c].value = counters_[c].reload;
-
- switch(c) {
- case 0: return irq_a_.apply(IRQA::Timer0);
- case 1: return irq_a_.apply(IRQA::Timer1);
- case 3: {
- serial_.shift();
- keyboard_.update();
-
- const uint8_t events = serial_.events(IOCParty);
- bool did_interrupt = false;
- if(events & HalfDuplexSerial::Receive) {
- did_interrupt |= irq_b_.apply(IRQB::KeyboardReceiveFull);
- }
- if(events & HalfDuplexSerial::Transmit) {
- did_interrupt |= irq_b_.apply(IRQB::KeyboardTransmitEmpty);
- }
-
- return did_interrupt;
- }
- default: break;
- }
- // TODO: events for timers 2 (baud).
- }
-
- return false;
- }
-
- bool tick_timers() {
- bool did_change_interrupts = false;
- did_change_interrupts |= tick_timer<0>();
- did_change_interrupts |= tick_timer<1>();
- did_change_interrupts |= tick_timer<2>();
- did_change_interrupts |= tick_timer<3>();
- return did_change_interrupts;
- }
-
- static constexpr uint32_t AddressMask = 0x1f'ffff;
-
- bool read(uint32_t address, uint8_t &value) {
- const auto target = address & AddressMask;
- value = 0xff;
- switch(target) {
- default:
- logger.error().append("Unrecognised IOC read from %08x", address);
- break;
-
- case 0x3200000 & AddressMask:
- value = control_ | 0xc0;
- value &= ~(i2c_.clock() ? 2 : 0);
- value &= ~(i2c_.data() ? 1 : 0);
-// logger.error().append("IOC control read: C:%d D:%d", !(value & 2), !(value & 1));
- return true;
-
- case 0x3200004 & AddressMask:
- value = serial_.input(IOCParty);
- irq_b_.clear(IRQB::KeyboardReceiveFull);
- logger.error().append("IOC keyboard receive: %02x", value);
- return true;
-
- // IRQ A.
- case 0x3200010 & AddressMask:
- value = irq_a_.status;
-// logger.error().append("IRQ A status is %02x", value);
- return true;
- case 0x3200014 & AddressMask:
- value = irq_a_.request();
- logger.error().append("IRQ A request is %02x", value);
- return true;
- case 0x3200018 & AddressMask:
- value = irq_a_.mask;
- logger.error().append("IRQ A mask is %02x", value);
- return true;
-
- // IRQ B.
- case 0x3200020 & AddressMask:
- value = irq_b_.status;
-// logger.error().append("IRQ B status is %02x", value);
- return true;
- case 0x3200024 & AddressMask:
- value = irq_b_.request();
- logger.error().append("IRQ B request is %02x", value);
- return true;
- case 0x3200028 & AddressMask:
- value = irq_b_.mask;
- logger.error().append("IRQ B mask is %02x", value);
- return true;
-
- // FIQ.
- case 0x3200030 & AddressMask:
- value = fiq_.status;
- logger.error().append("FIQ status is %02x", value);
- return true;
- case 0x3200034 & AddressMask:
- value = fiq_.request();
- logger.error().append("FIQ request is %02x", value);
- return true;
- case 0x3200038 & AddressMask:
- value = fiq_.mask;
- logger.error().append("FIQ mask is %02x", value);
- return true;
-
- // Counters.
- case 0x3200040 & AddressMask:
- case 0x3200050 & AddressMask:
- case 0x3200060 & AddressMask:
- case 0x3200070 & AddressMask:
- value = counters_[(target >> 4) - 0x4].output & 0xff;
-// logger.error().append("%02x: Counter %d low is %02x", target, (target >> 4) - 0x4, value);
- return true;
-
- case 0x3200044 & AddressMask:
- case 0x3200054 & AddressMask:
- case 0x3200064 & AddressMask:
- case 0x3200074 & AddressMask:
- value = counters_[(target >> 4) - 0x4].output >> 8;
-// logger.error().append("%02x: Counter %d high is %02x", target, (target >> 4) - 0x4, value);
- return true;
- }
-
- return true;
- }
-
- bool write(uint32_t address, uint8_t value) {
- const auto target = address & AddressMask;
- switch(target) {
- default:
- logger.error().append("Unrecognised IOC write of %02x at %08x", value, address);
- break;
-
- case 0x320'0000 & AddressMask:
- // TODO: does the rest of the control register relate to anything?
-// logger.error().append("TODO: IOC control write: C:%d D:%d", !(value & 2), !(value & 1));
-
- control_ = value;
- i2c_.set_clock_data(!(value & 2), !(value & 1));
- return true;
-
- case 0x320'0004 & AddressMask:
- logger.error().append("IOC keyboard transmit %02x", value);
- serial_.output(IOCParty, value);
- irq_b_.clear(IRQB::KeyboardTransmitEmpty);
- return true;
-
- case 0x320'0014 & AddressMask:
- // b2: clear IF.
- // b3: clear IR.
- // b4: clear POR.
- // b5: clear TM[0].
- // b6: clear TM[1].
- irq_a_.clear(value & 0x7c);
- return true;
-
- // Interrupts.
- case 0x320'0018 & AddressMask: irq_a_.mask = value; return true;
- case 0x320'0028 & AddressMask: irq_b_.mask = value; return true;
- case 0x320'0038 & AddressMask: fiq_.mask = value; return true;
-
- // Counters.
- case 0x320'0040 & AddressMask:
- case 0x320'0050 & AddressMask:
- case 0x320'0060 & AddressMask:
- case 0x320'0070 & AddressMask:
- counters_[(target >> 4) - 0x4].reload = uint16_t(
- (counters_[(target >> 4) - 0x4].reload & 0xff00) | value
- );
- return true;
-
- case 0x320'0044 & AddressMask:
- case 0x320'0054 & AddressMask:
- case 0x320'0064 & AddressMask:
- case 0x320'0074 & AddressMask:
- counters_[(target >> 4) - 0x4].reload = uint16_t(
- (counters_[(target >> 4) - 0x4].reload & 0x00ff) | (value << 8)
- );
- return true;
-
- case 0x320'0048 & AddressMask:
- case 0x320'0058 & AddressMask:
- case 0x320'0068 & AddressMask:
- case 0x320'0078 & AddressMask:
- counters_[(target >> 4) - 0x4].value = counters_[(target >> 4) - 0x4].reload;
- return true;
-
- case 0x320'004c & AddressMask:
- case 0x320'005c & AddressMask:
- case 0x320'006c & AddressMask:
- case 0x320'007c & AddressMask:
- counters_[(target >> 4) - 0x4].output = counters_[(target >> 4) - 0x4].value;
- return true;
-
- case 0x327'0000 & AddressMask:
- logger.error().append("TODO: exteded external podule space");
- return true;
-
- case 0x331'0000 & AddressMask:
- logger.error().append("TODO: 1772 / disk write");
- return true;
-
- case 0x335'0000 & AddressMask:
- logger.error().append("TODO: LS374 / printer data write");
- return true;
-
- case 0x335'0018 & AddressMask:
- logger.error().append("TODO: latch B write: %02x", value);
- return true;
-
- case 0x335'0040 & AddressMask:
- logger.error().append("TODO: latch A write: %02x", value);
- return true;
-
- case 0x335'0048 & AddressMask:
- logger.error().append("TODO: latch C write: %02x", value);
- return true;
-
- case 0x336'0000 & AddressMask:
- logger.error().append("TODO: podule interrupt request");
- return true;
-
- case 0x336'0004 & AddressMask:
- logger.error().append("TODO: podule interrupt mask");
- return true;
-
- case 0x33a'0000 & AddressMask:
- logger.error().append("TODO: 6854 / econet write");
- return true;
-
- case 0x33b'0000 & AddressMask:
- logger.error().append("TODO: 6551 / serial line write");
- return true;
- }
-
- return true;
- }
-
- InputOutput() : keyboard_(serial_) {
- irq_a_.status = IRQA::SetAlways | IRQA::PowerOnReset;
- irq_b_.status = 0x00;
- fiq_.status = 0x80; // 'set always'.
-
- i2c_.add_peripheral(&cmos_, 0xa0);
- }
-
- Audio &audio() {
- return audio_;
- }
-
- bool tick_audio() {
- if(audio_.tick()) {
- if(audio_.interrupt()) {
- irq_b_.apply(IRQB::SoundBufferPointerUsed);
- } else {
- irq_b_.clear(IRQB::SoundBufferPointerUsed);
- }
- return true;
- }
- return false;
- }
-
- void swap_audio() {
- audio_.swap();
- irq_b_.clear(IRQB::SoundBufferPointerUsed);
- }
-
-private:
- // IRQA, IRQB and FIQ states.
- struct Interrupt {
- uint8_t status, mask;
- uint8_t request() const {
- return status & mask;
- }
- bool apply(uint8_t value) {
- status |= value;
- return status & mask;
- }
- void clear(uint8_t bits) {
- status &= ~bits;
- }
- };
- Interrupt irq_a_, irq_b_, fiq_;
-
- // The IOCs four counters.
- struct Counter {
- uint16_t value;
- uint16_t reload;
- uint16_t output;
- };
- Counter counters_[4];
-
- // The KART and keyboard beyond it.
- HalfDuplexSerial serial_;
- Keyboard keyboard_;
-
- // The control register.
- uint8_t control_ = 0xff;
-
- // The I2C bus.
- I2C::Bus i2c_;
- CMOSRAM cmos_;
-
- // Audio.
- Audio audio_;
-};
-
-/// Primarily models the MEMC.
-template <typename IOCWriteDelegateT>
-struct Memory {
- Memory(IOCWriteDelegateT &ioc_write_delegate) : ioc_write_delegate_(ioc_write_delegate) {}
-
- int interrupt_mask() const {
- return ioc_.interrupt_mask();
- }
-
- void set_rom(const std::vector<uint8_t> &rom) {
- std::copy(
- rom.begin(),
- rom.begin() + static_cast<ptrdiff_t>(std::min(rom.size(), rom_.size())),
- rom_.begin());
- }
-
- template <typename IntT>
- uint32_t aligned(uint32_t address) {
- if constexpr (std::is_same_v<IntT, uint32_t>) {
- return address & static_cast<uint32_t>(~3);
- }
- return address;
- }
-
- template <typename IntT>
- bool write(uint32_t address, IntT source, InstructionSet::ARM::Mode mode, bool) {
- // User mode may only _write_ to logically-mapped RAM (subject to further testing below).
- if(mode == InstructionSet::ARM::Mode::User && address >= 0x200'0000) {
- return false;
- }
-
- switch(write_zones_[(address >> 21) & 31]) {
- case Zone::DMAAndMEMC: {
- const auto buffer_address = [](uint32_t source) -> uint32_t {
- return (source & 0x1fffc0) << 2;
- };
-
- // The MEMC itself isn't on the data bus; all values below should be taken from `address`.
- switch((address >> 17) & 0b111) {
- case 0b000:
- logger.error().append("TODO: DMA/MEMC Vinit = %04x", address & 0x1fffc0);
- return true;
-
- case 0b001:
- logger.error().append("TODO: DMA/MEMC Vstart = %04x", address & 0x1fffc0);
- return true;
-
- case 0b010:
- logger.error().append("TODO: DMA/MEMC Vend = %04x", address & 0x1fffc0);
- return true;
-
- case 0b011:
- logger.error().append("TODO: DMA/MEMC Cinit = %04x", address & 0x1fffc0);
- return true;
-
- case 0b100:
- logger.error().append("TODO: DMA/MEMC Sstart = %04x", address & 0x1fffc0);
- ioc_.audio().set_next_start(buffer_address(address));
- return true;
-
- case 0b101:
- logger.error().append("TODO: DMA/MEMC SendN = %04x", address & 0x1fffc0);
- ioc_.audio().set_next_end(buffer_address(address));
- return true;
-
- case 0b110:
- logger.error().append("TODO: DMA/MEMC Sptr");
- ioc_.swap_audio();
- return true;
-
- case 0b111:
- os_mode_ = address & (1 << 12);
- audio_dma_enable_ = address & (1 << 11);
- video_dma_enable_ = address & (1 << 10);
- switch((address >> 8) & 3) {
- default:
- dynamic_ram_refresh_ = DynamicRAMRefresh::None;
- break;
- case 0b01:
- case 0b11:
- dynamic_ram_refresh_ = DynamicRAMRefresh((address >> 8) & 3);
- break;
- }
- high_rom_access_time_ = ROMAccessTime((address >> 6) & 3);
- low_rom_access_time_ = ROMAccessTime((address >> 4) & 3);
- page_size_ = PageSize((address >> 2) & 3);
-
- logger.info().append("MEMC Control: %08x -> OS:%d audio:%d video:%d refresh:%d high:%d low:%d size:%d", address, os_mode_, audio_dma_enable_, video_dma_enable_, dynamic_ram_refresh_, high_rom_access_time_, low_rom_access_time_, page_size_);
- map_dirty_ = true;
- return true;
- }
- } break;
-
- case Zone::LogicallyMappedRAM: {
- const auto item = logical_ram<IntT, false>(address, mode);
- if(!item) {
- return false;
- }
- *item = source;
- return true;
- } break;
-
- case Zone::IOControllers:
- // TODO: have I overrestricted the value type for the IOC area?
- ioc_.write(address, uint8_t(source));
- ioc_write_delegate_.did_write_ioc();
- return true;
-
- case Zone::VideoController:
- // TODO: handle byte writes correctly.
- vidc_.write(source);
- break;
-
- case Zone::PhysicallyMappedRAM:
- physical_ram<IntT>(address) = source;
- return true;
-
- case Zone::AddressTranslator:
-// printf("Translator write at %08x; replaces %08x\n", address, pages_[address & 0x7f]);
- pages_[address & 0x7f] = address;
- map_dirty_ = true;
- break;
-
- default:
-// printf("TODO: write of %08x to %08x [%lu]\n", source, address, sizeof(IntT));
- break;
- }
-
- return true;
- }
-
- template <typename IntT>
- bool read(uint32_t address, IntT &source, InstructionSet::ARM::Mode mode, bool) {
- // User mode may only read logically-maped RAM and ROM.
- if(mode == InstructionSet::ARM::Mode::User && address >= 0x200'0000 && address < 0x380'0000) {
- return false;
- }
-
- switch (read_zones_[(address >> 21) & 31]) {
- case Zone::PhysicallyMappedRAM:
- source = physical_ram<IntT>(address);
- return true;
-
- case Zone::LogicallyMappedRAM: {
- if(!has_moved_rom_) { // TODO: maintain this state in the zones table.
- source = high_rom<IntT>(address);
- return true;
- }
-
- const auto item = logical_ram<IntT, true>(address, mode);
- if(!item) {
- return false;
- }
- source = *item;
- return true;
- } break;
-
- case Zone::LowROM:
-// logger.error().append("TODO: Low ROM read from %08x", address);
- source = IntT(~0);
- return true;
-
- case Zone::HighROM:
- // Real test is: require A24=A25=0, then A25=1.
- // TODO: as above, move this test into the zones tables.
- has_moved_rom_ = true;
- source = high_rom<IntT>(address);
- return true;
-
- case Zone::IOControllers: {
- if constexpr (std::is_same_v<IntT, uint8_t>) {
- ioc_.read(address, source);
- return true;
- } else {
- // TODO: generalise this adaptation of an 8-bit device to the 32-bit bus, which probably isn't right anyway.
- uint8_t value;
- ioc_.read(address, value);
- source = value;
- return true;
- }
- }
-
- default:
- logger.error().append("TODO: read from %08x", address);
- break;
- }
-
- source = 0;
- return false;
- }
-
- bool tick_timers() {
- return ioc_.tick_timers();
- }
-
- bool tick_audio() {
- // TODO: does disabling audio DMA pause output, or leave it ticking and merely
- // stop allowing it to use the bus?
- return ioc_.tick_audio();
- }
-
- private:
- bool has_moved_rom_ = false;
- std::array<uint8_t, 4*1024*1024> ram_{};
- std::array<uint8_t, 2*1024*1024> rom_;
- InputOutput ioc_;
- Video vidc_;
- IOCWriteDelegateT &ioc_write_delegate_;
-
- template <typename IntT>
- IntT &physical_ram(uint32_t address) {
- address = aligned<IntT>(address);
- address &= (ram_.size() - 1);
- return *reinterpret_cast<IntT *>(&ram_[address]);
- }
-
- template <typename IntT>
- IntT &high_rom(uint32_t address) {
- address = aligned<IntT>(address);
- return *reinterpret_cast<IntT *>(&rom_[address & (rom_.size() - 1)]);
- }
-
- static constexpr std::array<Zone, 0x20> read_zones_ = zones(true);
- static constexpr std::array<Zone, 0x20> write_zones_ = zones(false);
-
- // Control register values.
- bool os_mode_ = false;
- bool audio_dma_enable_ = false;
- bool video_dma_enable_ = false; // "Unaffected" by reset, so here picked arbitrarily.
-
- enum class DynamicRAMRefresh {
- None = 0b00,
- DuringFlyback = 0b01,
- Continuous = 0b11,
- } dynamic_ram_refresh_ = DynamicRAMRefresh::None; // State at reset is undefined; constrain to a valid enum value.
-
- enum class ROMAccessTime {
- ns450 = 0b00,
- ns325 = 0b01,
- ns200 = 0b10,
- ns200with60nsNibble = 0b11,
- } high_rom_access_time_ = ROMAccessTime::ns450, low_rom_access_time_ = ROMAccessTime::ns450;
-
- enum class PageSize {
- kb4 = 0b00,
- kb8 = 0b01,
- kb16 = 0b10,
- kb32 = 0b11,
- } page_size_ = PageSize::kb4;
-
- // Address translator.
- //
- // MEMC contains one entry per a physical page number, indicating where it goes logically.
- // Any logical access is tested against all 128 mappings. So that's backwards compared to
- // the ideal for an emulator, which would map from logical to physical, even if a lot more
- // compact — there are always 128 physical pages; there are up to 8192 logical pages.
- //
- // So captured here are both the physical -> logical map as representative of the real
- // hardware, and the reverse logical -> physical map, which is built (and rebuilt, and rebuilt)
- // from the other.
-
- // Physical to logical mapping.
- std::array<uint32_t, 128> pages_{};
-
- // Logical to physical mapping.
- struct MappedPage {
- uint8_t *target = nullptr;
- uint8_t protection_level = 0;
- };
- std::array<MappedPage, 8192> mapping_;
- bool map_dirty_ = true;
-
- template <typename IntT, bool is_read>
- IntT *logical_ram(uint32_t address, InstructionSet::ARM::Mode mode) {
- // Possibly TODO: this recompute-if-dirty flag is supposed to ameliorate for an expensive
- // mapping process. It can be eliminated when the process is improved.
- if(map_dirty_) {
- update_mapping();
- map_dirty_ = false;
- }
-
- address = aligned<IntT>(address);
- address &= 0x1ff'ffff;
- size_t page;
-
- // TODO: eliminate switch here.
- switch(page_size_) {
- default:
- case PageSize::kb4:
- page = address >> 12;
- address &= 0x0fff;
- break;
- case PageSize::kb8:
- page = address >> 13;
- address &= 0x1fff;
- break;
- case PageSize::kb16:
- page = address >> 14;
- address &= 0x3fff;
- break;
- case PageSize::kb32:
- page = address >> 15;
- address &= 0x7fff;
- break;
- }
-
- if(!mapping_[page].target) {
- return nullptr;
- }
-
- // TODO: eliminate switch here.
- // Top of my head idea: is_read, is_user and is_os_mode make three bits, so
- // keep a one-byte bitmap of permitted accesses rather than the raw protection
- // level?
- switch(mapping_[page].protection_level) {
- case 0b00: break;
- case 0b01:
- if(!is_read && mode == InstructionSet::ARM::Mode::User) {
- return nullptr;
- }
- break;
- default:
- if(mode == InstructionSet::ARM::Mode::User) {
- return nullptr;
- }
- if(!is_read && !os_mode_) {
- return nullptr;
- }
- break;
- }
-
- return reinterpret_cast<IntT *>(mapping_[page].target + address);
- }
-
- void update_mapping() {
- // For each physical page, project it into logical space.
- switch(page_size_) {
- default:
- case PageSize::kb4: update_mapping<PageSize::kb4>(); break;
- case PageSize::kb8: update_mapping<PageSize::kb8>(); break;
- case PageSize::kb16: update_mapping<PageSize::kb16>(); break;
- case PageSize::kb32: update_mapping<PageSize::kb32>(); break;
- }
- }
-
- template <PageSize size>
- void update_mapping() {
- // Clear all logical mappings.
- std::fill(mapping_.begin(), mapping_.end(), MappedPage{});
-
- // For each physical page, project it into logical space
- // and store it.
- for(const auto page: pages_) {
- uint32_t physical, logical;
-
- switch(size) {
- case PageSize::kb4:
- // 4kb:
- // A[6:0] -> PPN[6:0]
- // A[11:10] -> LPN[12:11]; A[22:12] -> LPN[10:0] i.e. 8192 logical pages
- physical = page & BitMask<6, 0>::value;
-
- physical <<= 12;
-
- logical = (page & BitMask<11, 10>::value) << 1;
- logical |= (page & BitMask<22, 12>::value) >> 12;
- break;
-
- case PageSize::kb8:
- // 8kb:
- // A[0] -> PPN[6]; A[6:1] -> PPN[5:0]
- // A[11:10] -> LPN[11:10]; A[22:13] -> LPN[9:0] i.e. 4096 logical pages
- physical = (page & BitMask<0, 0>::value) << 6;
- physical |= (page & BitMask<6, 1>::value) >> 1;
-
- physical <<= 13;
-
- logical = page & BitMask<11, 10>::value;
- logical |= (page & BitMask<22, 13>::value) >> 13;
- break;
-
- case PageSize::kb16:
- // 16kb:
- // A[1:0] -> PPN[6:5]; A[6:2] -> PPN[4:0]
- // A[11:10] -> LPN[10:9]; A[22:14] -> LPN[8:0] i.e. 2048 logical pages
- physical = (page & BitMask<1, 0>::value) << 5;
- physical |= (page & BitMask<6, 2>::value) >> 2;
-
- physical <<= 14;
-
- logical = (page & BitMask<11, 10>::value) >> 1;
- logical |= (page & BitMask<22, 14>::value) >> 14;
- break;
-
- case PageSize::kb32:
- // 32kb:
- // A[1] -> PPN[6]; A[2] -> PPN[5]; A[0] -> PPN[4]; A[6:3] -> PPN[3:0]
- // A[11:10] -> LPN[9:8]; A[22:15] -> LPN[7:0] i.e. 1024 logical pages
- physical = (page & BitMask<1, 1>::value) << 5;
- physical |= (page & BitMask<2, 2>::value) << 3;
- physical |= (page & BitMask<0, 0>::value) << 4;
- physical |= (page & BitMask<6, 3>::value) >> 3;
-
- physical <<= 15;
-
- logical = (page & BitMask<11, 10>::value) >> 2;
- logical |= (page & BitMask<22, 15>::value) >> 15;
- break;
- }
-
-// printf("%08x => physical %d -> logical %d\n", page, (physical >> 15), logical);
-
- // TODO: consider clashes.
- // TODO: what if there's less than 4mb present?
- mapping_[logical].target = &ram_[physical];
- mapping_[logical].protection_level = (page >> 8) & 3;
- }
- }
-};
-
class ConcreteMachine:
public Machine,
public MachineTypes::MediaTarget,
@@ -1139,36 +64,14 @@ class ConcreteMachine:
// * timers: 2;
// * audio: 1. [TODO]
- tick_cpu();
- tick_cpu();
- tick_cpu();
- tick_cpu();
-
- tick_cpu();
- tick_cpu();
- tick_cpu();
- tick_cpu();
-
- tick_cpu();
- tick_cpu();
- tick_cpu();
- tick_cpu();
+ tick_cpu(); tick_cpu(); tick_cpu(); tick_cpu();
+ tick_cpu(); tick_cpu(); tick_cpu(); tick_cpu();
+ tick_cpu(); tick_cpu(); tick_cpu(); tick_cpu();
tick_timers();
- tick_cpu();
- tick_cpu();
- tick_cpu();
- tick_cpu();
-
- tick_cpu();
- tick_cpu();
- tick_cpu();
- tick_cpu();
-
- tick_cpu();
- tick_cpu();
- tick_cpu();
- tick_cpu();
+ tick_cpu(); tick_cpu(); tick_cpu(); tick_cpu();
+ tick_cpu(); tick_cpu(); tick_cpu(); tick_cpu();
+ tick_cpu(); tick_cpu(); tick_cpu(); tick_cpu();
tick_timers();
tick_audio();
}
@@ -1192,8 +95,16 @@ class ConcreteMachine:
insert_media(target.media);
}
- void did_write_ioc() {
- test_interrupts();
+ void update_interrupts() {
+ using Exception = InstructionSet::ARM::Registers::Exception;
+
+ const int requests = executor_.bus.interrupt_mask();
+ if((requests & InterruptRequests::FIQ) && executor_.registers().interrupt<Exception::FIQ>()) {
+ return;
+ }
+ if(requests & InterruptRequests::IRQ) {
+ executor_.registers().interrupt<Exception::IRQ>();
+ }
}
private:
@@ -1290,29 +201,8 @@ class ConcreteMachine:
// }
}
- void test_interrupts() {
- using Exception = InstructionSet::ARM::Registers::Exception;
-
- const int requests = executor_.bus.interrupt_mask();
- if((requests & InterruptRequests::FIQ) && executor_.registers().interrupt<Exception::FIQ>()) {
- return;
- }
- if(requests & InterruptRequests::IRQ) {
- executor_.registers().interrupt<Exception::IRQ>();
- }
- }
-
- void tick_timers() {
- if(executor_.bus.tick_timers()) {
- test_interrupts();
- }
- }
-
- void tick_audio() {
- if(executor_.bus.tick_audio()) {
- test_interrupts();
- }
- }
+ void tick_timers() { executor_.bus.tick_timers(); }
+ void tick_audio() { executor_.bus.tick_audio(); }
// MARK: - MediaTarget
bool insert_media(const Analyser::Static::Media &) override {
@@ -1328,7 +218,7 @@ class ConcreteMachine:
// MARK: - ARM execution
static constexpr auto arm_model = InstructionSet::ARM::Model::ARMv2;
- InstructionSet::ARM::Executor<arm_model, Memory<ConcreteMachine>> executor_;
+ InstructionSet::ARM::Executor<arm_model, MemoryController<ConcreteMachine>> executor_;
};
}
diff --git a/Machines/Acorn/Archimedes/CMOSRAM.hpp b/Machines/Acorn/Archimedes/CMOSRAM.hpp
new file mode 100644
index 000000000..4b2ff6102
--- /dev/null
+++ b/Machines/Acorn/Archimedes/CMOSRAM.hpp
@@ -0,0 +1,19 @@
+//
+// CMOSRAM.hpp
+// Clock Signal
+//
+// Created by Thomas Harte on 20/03/2024.
+// Copyright © 2024 Thomas Harte. All rights reserved.
+//
+
+#pragma once
+
+#include "../../../Components/I2C/I2C.hpp"
+
+namespace Archimedes {
+
+struct CMOSRAM: public I2C::Peripheral {
+ // All TODO.
+};
+
+}
diff --git a/Machines/Acorn/Archimedes/HalfDuplexSerial.hpp b/Machines/Acorn/Archimedes/HalfDuplexSerial.hpp
new file mode 100644
index 000000000..e47a0a17d
--- /dev/null
+++ b/Machines/Acorn/Archimedes/HalfDuplexSerial.hpp
@@ -0,0 +1,88 @@
+//
+// HalfDuplexSerial.hpp
+// Clock Signal
+//
+// Created by Thomas Harte on 20/03/2024.
+// Copyright © 2024 Thomas Harte. All rights reserved.
+//
+
+#pragma once
+
+namespace Archimedes {
+
+/// Models a half-duplex serial link between two parties, framing bytes with one start bit and two stop bits.
+struct HalfDuplexSerial {
+ static constexpr uint16_t ShiftMask = 0b1111'1110'0000'0000;
+
+ /// Enqueues @c value for output.
+ void output(int party, uint8_t value) {
+ parties_[party].output_count = 11;
+ parties_[party].input = 0x7ff;
+ parties_[party].output = uint16_t((value << 1) | ShiftMask);
+ }
+
+ /// @returns The last observed input.
+ uint8_t input(int party) const {
+ return uint8_t(parties_[party].input >> 1);
+ }
+
+ static constexpr uint8_t Receive = 1 << 0;
+ static constexpr uint8_t Transmit = 1 << 1;
+
+ /// @returns A bitmask of events that occurred during the last shift.
+ uint8_t events(int party) {
+ const auto result = parties_[party].events;
+ parties_[party].events = 0;
+ return result;
+ }
+
+ bool is_outputting(int party) const {
+ return parties_[party].output_count != 11;
+ }
+
+ /// Updates the shifters on both sides of the serial link.
+ void shift() {
+ const uint16_t next = parties_[0].output & parties_[1].output & 1;
+
+ for(int c = 0; c < 2; c++) {
+ if(parties_[c].output_count) {
+ --parties_[c].output_count;
+ if(!parties_[c].output_count) {
+ parties_[c].events |= Transmit;
+ parties_[c].input_count = -1;
+ }
+ parties_[c].output = (parties_[c].output >> 1) | ShiftMask;
+ } else {
+ // Check for a start bit.
+ if(parties_[c].input_count == -1 && !next) {
+ parties_[c].input_count = 0;
+ }
+
+ // Shift in if currently observing.
+ if(parties_[c].input_count >= 0 && parties_[c].input_count < 11) {
+ parties_[c].input = uint16_t((parties_[c].input >> 1) | (next << 10));
+
+ ++parties_[c].input_count;
+ if(parties_[c].input_count == 11) {
+ parties_[c].events |= Receive;
+ parties_[c].input_count = -1;
+ }
+ }
+ }
+ }
+ }
+
+private:
+ struct Party {
+ int output_count = 0;
+ int input_count = -1;
+ uint16_t output = 0xffff;
+ uint16_t input = 0;
+ uint8_t events = 0;
+ } parties_[2];
+};
+
+static constexpr int IOCParty = 0;
+static constexpr int KeyboardParty = 1;
+
+}
diff --git a/Machines/Acorn/Archimedes/InputOutputController.hpp b/Machines/Acorn/Archimedes/InputOutputController.hpp
new file mode 100644
index 000000000..94c617144
--- /dev/null
+++ b/Machines/Acorn/Archimedes/InputOutputController.hpp
@@ -0,0 +1,380 @@
+//
+// InputOutputController.h
+// Clock Signal
+//
+// Created by Thomas Harte on 20/03/2024.
+// Copyright © 2024 Thomas Harte. All rights reserved.
+//
+
+#pragma once
+
+#include "../../../Outputs/Log.hpp"
+
+#include "CMOSRAM.hpp"
+#include "Keyboard.hpp"
+#include "Sound.hpp"
+
+namespace Archimedes {
+
+// IRQ A flags
+namespace IRQA {
+ // The first four of these are taken from the A500 documentation and may be inaccurate.
+ static constexpr uint8_t PrinterBusy = 0x01;
+ static constexpr uint8_t SerialRinging = 0x02;
+ static constexpr uint8_t PrinterAcknowledge = 0x04;
+ static constexpr uint8_t VerticalFlyback = 0x08;
+ static constexpr uint8_t PowerOnReset = 0x10;
+ static constexpr uint8_t Timer0 = 0x20;
+ static constexpr uint8_t Timer1 = 0x40;
+ static constexpr uint8_t SetAlways = 0x80;
+}
+
+// IRQ B flags
+namespace IRQB {
+ // These are taken from the A3010 documentation.
+ static constexpr uint8_t PoduleFIQRequest = 0x01;
+ static constexpr uint8_t SoundBufferPointerUsed = 0x02;
+ static constexpr uint8_t SerialLine = 0x04;
+ static constexpr uint8_t IDE = 0x08;
+ static constexpr uint8_t FloppyDiscInterrupt = 0x10;
+ static constexpr uint8_t PoduleIRQRequest = 0x20;
+ static constexpr uint8_t KeyboardTransmitEmpty = 0x40;
+ static constexpr uint8_t KeyboardReceiveFull = 0x80;
+}
+
+// FIQ flags
+namespace FIQ {
+ // These are taken from the A3010 documentation.
+ static constexpr uint8_t FloppyDiscData = 0x01;
+ static constexpr uint8_t SerialLine = 0x10;
+ static constexpr uint8_t PoduleFIQRequest = 0x40;
+ static constexpr uint8_t SetAlways = 0x80;
+}
+
+namespace InterruptRequests {
+ static constexpr int IRQ = 0x01;
+ static constexpr int FIQ = 0x02;
+};
+
+template <typename InterruptObserverT>
+struct InputOutputController {
+ int interrupt_mask() const {
+ return
+ ((irq_a_.request() | irq_b_.request()) ? InterruptRequests::IRQ : 0) |
+ (fiq_.request() ? InterruptRequests::FIQ : 0);
+ }
+
+ template <int c>
+ bool tick_timer() {
+ if(!counters_[c].value && !counters_[c].reload) {
+ return false;
+ }
+
+ --counters_[c].value;
+ if(!counters_[c].value) {
+ counters_[c].value = counters_[c].reload;
+
+ switch(c) {
+ case 0: return irq_a_.set(IRQA::Timer0);
+ case 1: return irq_a_.set(IRQA::Timer1);
+ case 3: {
+ serial_.shift();
+ keyboard_.update();
+
+ const uint8_t events = serial_.events(IOCParty);
+ bool did_interrupt = false;
+ if(events & HalfDuplexSerial::Receive) {
+ did_interrupt |= irq_b_.set(IRQB::KeyboardReceiveFull);
+ }
+ if(events & HalfDuplexSerial::Transmit) {
+ did_interrupt |= irq_b_.set(IRQB::KeyboardTransmitEmpty);
+ }
+
+ return did_interrupt;
+ }
+ default: break;
+ }
+ // TODO: events for timers 2 (baud).
+ }
+
+ return false;
+ }
+
+ bool tick_timers() {
+ bool did_change_interrupts = false;
+ did_change_interrupts |= tick_timer<0>();
+ did_change_interrupts |= tick_timer<1>();
+ did_change_interrupts |= tick_timer<2>();
+ did_change_interrupts |= tick_timer<3>();
+ return did_change_interrupts;
+ }
+
+ static constexpr uint32_t AddressMask = 0x1f'ffff;
+
+ bool read(uint32_t address, uint8_t &value) {
+ const auto target = address & AddressMask;
+ value = 0xff;
+ switch(target) {
+ default:
+ logger.error().append("Unrecognised IOC read from %08x", address);
+ break;
+
+ case 0x3200000 & AddressMask:
+ value = control_ | 0xc0;
+ value &= ~(i2c_.clock() ? 2 : 0);
+ value &= ~(i2c_.data() ? 1 : 0);
+// logger.error().append("IOC control read: C:%d D:%d", !(value & 2), !(value & 1));
+ return true;
+
+ case 0x3200004 & AddressMask:
+ value = serial_.input(IOCParty);
+ irq_b_.clear(IRQB::KeyboardReceiveFull);
+ logger.error().append("IOC keyboard receive: %02x", value);
+ return true;
+
+ // IRQ A.
+ case 0x3200010 & AddressMask:
+ value = irq_a_.status;
+// logger.error().append("IRQ A status is %02x", value);
+ return true;
+ case 0x3200014 & AddressMask:
+ value = irq_a_.request();
+ logger.error().append("IRQ A request is %02x", value);
+ return true;
+ case 0x3200018 & AddressMask:
+ value = irq_a_.mask;
+ logger.error().append("IRQ A mask is %02x", value);
+ return true;
+
+ // IRQ B.
+ case 0x3200020 & AddressMask:
+ value = irq_b_.status;
+// logger.error().append("IRQ B status is %02x", value);
+ return true;
+ case 0x3200024 & AddressMask:
+ value = irq_b_.request();
+ logger.error().append("IRQ B request is %02x", value);
+ return true;
+ case 0x3200028 & AddressMask:
+ value = irq_b_.mask;
+ logger.error().append("IRQ B mask is %02x", value);
+ return true;
+
+ // FIQ.
+ case 0x3200030 & AddressMask:
+ value = fiq_.status;
+ logger.error().append("FIQ status is %02x", value);
+ return true;
+ case 0x3200034 & AddressMask:
+ value = fiq_.request();
+ logger.error().append("FIQ request is %02x", value);
+ return true;
+ case 0x3200038 & AddressMask:
+ value = fiq_.mask;
+ logger.error().append("FIQ mask is %02x", value);
+ return true;
+
+ // Counters.
+ case 0x3200040 & AddressMask:
+ case 0x3200050 & AddressMask:
+ case 0x3200060 & AddressMask:
+ case 0x3200070 & AddressMask:
+ value = counters_[(target >> 4) - 0x4].output & 0xff;
+// logger.error().append("%02x: Counter %d low is %02x", target, (target >> 4) - 0x4, value);
+ return true;
+
+ case 0x3200044 & AddressMask:
+ case 0x3200054 & AddressMask:
+ case 0x3200064 & AddressMask:
+ case 0x3200074 & AddressMask:
+ value = counters_[(target >> 4) - 0x4].output >> 8;
+// logger.error().append("%02x: Counter %d high is %02x", target, (target >> 4) - 0x4, value);
+ return true;
+ }
+
+ return true;
+ }
+
+ bool write(uint32_t address, uint8_t value) {
+ const auto target = address & AddressMask;
+ switch(target) {
+ default:
+ logger.error().append("Unrecognised IOC write of %02x at %08x", value, address);
+ break;
+
+ case 0x320'0000 & AddressMask:
+ // TODO: does the rest of the control register relate to anything?
+// logger.error().append("TODO: IOC control write: C:%d D:%d", !(value & 2), !(value & 1));
+
+ control_ = value;
+ i2c_.set_clock_data(!(value & 2), !(value & 1));
+ return true;
+
+ case 0x320'0004 & AddressMask:
+ logger.error().append("IOC keyboard transmit %02x", value);
+ serial_.output(IOCParty, value);
+ irq_b_.clear(IRQB::KeyboardTransmitEmpty);
+ return true;
+
+ case 0x320'0014 & AddressMask:
+ // b2: clear IF.
+ // b3: clear IR.
+ // b4: clear POR.
+ // b5: clear TM[0].
+ // b6: clear TM[1].
+ irq_a_.clear(value & 0x7c);
+ return true;
+
+ // Interrupts.
+ case 0x320'0018 & AddressMask: irq_a_.mask = value; return true;
+ case 0x320'0028 & AddressMask: irq_b_.mask = value; return true;
+ case 0x320'0038 & AddressMask: fiq_.mask = value; return true;
+
+ // Counters.
+ case 0x320'0040 & AddressMask:
+ case 0x320'0050 & AddressMask:
+ case 0x320'0060 & AddressMask:
+ case 0x320'0070 & AddressMask:
+ counters_[(target >> 4) - 0x4].reload = uint16_t(
+ (counters_[(target >> 4) - 0x4].reload & 0xff00) | value
+ );
+ return true;
+
+ case 0x320'0044 & AddressMask:
+ case 0x320'0054 & AddressMask:
+ case 0x320'0064 & AddressMask:
+ case 0x320'0074 & AddressMask:
+ counters_[(target >> 4) - 0x4].reload = uint16_t(
+ (counters_[(target >> 4) - 0x4].reload & 0x00ff) | (value << 8)
+ );
+ return true;
+
+ case 0x320'0048 & AddressMask:
+ case 0x320'0058 & AddressMask:
+ case 0x320'0068 & AddressMask:
+ case 0x320'0078 & AddressMask:
+ counters_[(target >> 4) - 0x4].value = counters_[(target >> 4) - 0x4].reload;
+ return true;
+
+ case 0x320'004c & AddressMask:
+ case 0x320'005c & AddressMask:
+ case 0x320'006c & AddressMask:
+ case 0x320'007c & AddressMask:
+ counters_[(target >> 4) - 0x4].output = counters_[(target >> 4) - 0x4].value;
+ return true;
+
+ case 0x327'0000 & AddressMask:
+ logger.error().append("TODO: exteded external podule space");
+ return true;
+
+ case 0x331'0000 & AddressMask:
+ logger.error().append("TODO: 1772 / disk write");
+ return true;
+
+ case 0x335'0000 & AddressMask:
+ logger.error().append("TODO: LS374 / printer data write");
+ return true;
+
+ case 0x335'0018 & AddressMask:
+ logger.error().append("TODO: latch B write: %02x", value);
+ return true;
+
+ case 0x335'0040 & AddressMask:
+ logger.error().append("TODO: latch A write: %02x", value);
+ return true;
+
+ case 0x335'0048 & AddressMask:
+ logger.error().append("TODO: latch C write: %02x", value);
+ return true;
+
+ case 0x336'0000 & AddressMask:
+ logger.error().append("TODO: podule interrupt request");
+ return true;
+
+ case 0x336'0004 & AddressMask:
+ logger.error().append("TODO: podule interrupt mask");
+ return true;
+
+ case 0x33a'0000 & AddressMask:
+ logger.error().append("TODO: 6854 / econet write");
+ return true;
+
+ case 0x33b'0000 & AddressMask:
+ logger.error().append("TODO: 6551 / serial line write");
+ return true;
+ }
+
+ return true;
+ }
+
+ InputOutputController(InterruptObserverT &observer) :
+ observer_(observer),
+ keyboard_(serial_),
+ sound_(*this)
+ {
+ irq_a_.status = IRQA::SetAlways | IRQA::PowerOnReset;
+ irq_b_.status = 0x00;
+ fiq_.status = 0x80; // 'set always'.
+
+ i2c_.add_peripheral(&cmos_, 0xa0);
+ update_sound_interrupt();
+ }
+
+ Sound<InputOutputController> &sound() {
+ return sound_;
+ }
+
+ void update_sound_interrupt() {
+ if(sound_.interrupt()) {
+ irq_b_.set(IRQB::SoundBufferPointerUsed);
+ } else {
+ irq_b_.clear(IRQB::SoundBufferPointerUsed);
+ }
+ observer_.update_interrupts();
+ }
+
+private:
+ Log::Logger<Log::Source::ARMIOC> logger;
+ InterruptObserverT &observer_;
+
+ // IRQA, IRQB and FIQ states.
+ struct Interrupt {
+ uint8_t status, mask;
+ uint8_t request() const {
+ return status & mask;
+ }
+ bool set(uint8_t value) {
+ status |= value;
+ return status & mask;
+ }
+ void clear(uint8_t bits) {
+ status &= ~bits;
+ }
+ };
+ Interrupt irq_a_, irq_b_, fiq_;
+
+ // The IOCs four counters.
+ struct Counter {
+ uint16_t value;
+ uint16_t reload;
+ uint16_t output;
+ };
+ Counter counters_[4];
+
+ // The KART and keyboard beyond it.
+ HalfDuplexSerial serial_;
+ Keyboard keyboard_;
+
+ // The control register.
+ uint8_t control_ = 0xff;
+
+ // The I2C bus.
+ I2C::Bus i2c_;
+ CMOSRAM cmos_;
+
+ // Audio.
+ Sound<InputOutputController> sound_;
+};
+
+}
+
diff --git a/Machines/Acorn/Archimedes/Keyboard.hpp b/Machines/Acorn/Archimedes/Keyboard.hpp
new file mode 100644
index 000000000..5140e772b
--- /dev/null
+++ b/Machines/Acorn/Archimedes/Keyboard.hpp
@@ -0,0 +1,59 @@
+//
+// Keyboard.hpp
+// Clock Signal
+//
+// Created by Thomas Harte on 20/03/2024.
+// Copyright © 2024 Thomas Harte. All rights reserved.
+//
+
+#pragma once
+
+#include "HalfDuplexSerial.hpp"
+
+namespace Archimedes {
+
+// Resource for the keyboard protocol: https://github.com/tmk/tmk_keyboard/wiki/ACORN-ARCHIMEDES-Keyboard
+struct Keyboard {
+ Keyboard(HalfDuplexSerial &serial) : serial_(serial) {}
+
+ void update() {
+ if(serial_.events(KeyboardParty) & HalfDuplexSerial::Receive) {
+ const uint8_t input = serial_.input(KeyboardParty);
+ switch(input) {
+ case HRST:
+ // TODO:
+ case RAK1:
+ case RAK2:
+ serial_.output(KeyboardParty, input);
+ break;
+
+ case RQID:
+ serial_.output(KeyboardParty, 0x81); // TODO: what keyboard type?
+ break;
+
+ default:
+ printf("Keyboard declines to respond to %02x\n", input);
+ break;
+ }
+ }
+ }
+
+private:
+ HalfDuplexSerial &serial_;
+
+ static constexpr uint8_t HRST = 0b1111'1111; // Keyboard reset.
+ static constexpr uint8_t RAK1 = 0b1111'1110; // Reset response #1.
+ static constexpr uint8_t RAK2 = 0b1111'1101; // Reset response #2.
+
+ static constexpr uint8_t RQID = 0b0010'0000; // Request for keyboard ID.
+ static constexpr uint8_t RQMP = 0b0010'0010; // Request for mouse data.
+
+ static constexpr uint8_t BACK = 0b0011'1111; // Acknowledge for first keyboard data byte pair.
+ static constexpr uint8_t NACK = 0b0011'0000; // Acknowledge for last keyboard data byte pair, selects scan/mouse mode.
+ static constexpr uint8_t SACK = 0b0011'0001; // Last data byte acknowledge.
+ static constexpr uint8_t MACK = 0b0011'0010; // Last data byte acknowledge.
+ static constexpr uint8_t SMAK = 0b0011'0011; // Last data byte acknowledge.
+ static constexpr uint8_t PRST = 0b0010'0001; // Does nothing.
+};
+
+}
diff --git a/Machines/Acorn/Archimedes/MemoryController.hpp b/Machines/Acorn/Archimedes/MemoryController.hpp
new file mode 100644
index 000000000..ff200b8f5
--- /dev/null
+++ b/Machines/Acorn/Archimedes/MemoryController.hpp
@@ -0,0 +1,467 @@
+//
+// MemoryController.hpp
+// Clock Signal
+//
+// Created by Thomas Harte on 20/03/2024.
+// Copyright © 2024 Thomas Harte. All rights reserved.
+//
+
+#pragma once
+
+#include "InputOutputController.hpp"
+#include "Video.hpp"
+
+#include "../../../InstructionSets/ARM/Registers.hpp"
+#include "../../../Outputs/Log.hpp"
+
+namespace Archimedes {
+
+/// Provides the mask with all bits set in the range [start, end], where start must be >= end.
+template <int start, int end> struct BitMask {
+ static_assert(start >= end);
+ static constexpr uint32_t value = ((1 << (start + 1)) - 1) - ((1 << end) - 1);
+};
+static_assert(BitMask<0, 0>::value == 1);
+static_assert(BitMask<1, 1>::value == 2);
+static_assert(BitMask<15, 15>::value == 32768);
+static_assert(BitMask<15, 0>::value == 0xffff);
+static_assert(BitMask<15, 14>::value == 49152);
+
+/// Models the MEMC, making this the Archimedes bus. Owns various other chips on the bus as a result.
+template <typename InterruptObserverT>
+struct MemoryController {
+ MemoryController(InterruptObserverT &delegate) : ioc_(delegate) {}
+
+ int interrupt_mask() const {
+ return ioc_.interrupt_mask();
+ }
+
+ void set_rom(const std::vector<uint8_t> &rom) {
+ std::copy(
+ rom.begin(),
+ rom.begin() + static_cast<ptrdiff_t>(std::min(rom.size(), rom_.size())),
+ rom_.begin());
+ }
+
+ template <typename IntT>
+ uint32_t aligned(uint32_t address) {
+ if constexpr (std::is_same_v<IntT, uint32_t>) {
+ return address & static_cast<uint32_t>(~3);
+ }
+ return address;
+ }
+
+ template <typename IntT>
+ bool write(uint32_t address, IntT source, InstructionSet::ARM::Mode mode, bool) {
+ // User mode may only _write_ to logically-mapped RAM (subject to further testing below).
+ if(mode == InstructionSet::ARM::Mode::User && address >= 0x200'0000) {
+ return false;
+ }
+
+ switch(write_zones_[(address >> 21) & 31]) {
+ case Zone::DMAAndMEMC: {
+ const auto buffer_address = [](uint32_t source) -> uint32_t {
+ return (source & 0x1fffc0) << 2;
+ };
+
+ // The MEMC itself isn't on the data bus; all values below should be taken from `address`.
+ switch((address >> 17) & 0b111) {
+ case 0b000:
+ logger.error().append("TODO: DMA/MEMC Vinit = %04x", address & 0x1fffc0);
+ return true;
+
+ case 0b001:
+ logger.error().append("TODO: DMA/MEMC Vstart = %04x", address & 0x1fffc0);
+ return true;
+
+ case 0b010:
+ logger.error().append("TODO: DMA/MEMC Vend = %04x", address & 0x1fffc0);
+ return true;
+
+ case 0b011:
+ logger.error().append("TODO: DMA/MEMC Cinit = %04x", address & 0x1fffc0);
+ return true;
+
+ case 0b100: ioc_.sound().set_next_start(buffer_address(address)); return true;
+ case 0b101: ioc_.sound().set_next_end(buffer_address(address)); return true;
+ case 0b110: ioc_.sound().swap(); return true;
+
+ case 0b111:
+ os_mode_ = address & (1 << 12);
+ audio_dma_enable_ = address & (1 << 11);
+ video_dma_enable_ = address & (1 << 10);
+ switch((address >> 8) & 3) {
+ default:
+ dynamic_ram_refresh_ = DynamicRAMRefresh::None;
+ break;
+ case 0b01:
+ case 0b11:
+ dynamic_ram_refresh_ = DynamicRAMRefresh((address >> 8) & 3);
+ break;
+ }
+ high_rom_access_time_ = ROMAccessTime((address >> 6) & 3);
+ low_rom_access_time_ = ROMAccessTime((address >> 4) & 3);
+ page_size_ = PageSize((address >> 2) & 3);
+
+ logger.info().append("MEMC Control: %08x -> OS:%d audio:%d video:%d refresh:%d high:%d low:%d size:%d", address, os_mode_, audio_dma_enable_, video_dma_enable_, dynamic_ram_refresh_, high_rom_access_time_, low_rom_access_time_, page_size_);
+ map_dirty_ = true;
+ return true;
+ }
+ } break;
+
+ case Zone::LogicallyMappedRAM: {
+ const auto item = logical_ram<IntT, false>(address, mode);
+ if(!item) {
+ return false;
+ }
+ *item = source;
+ return true;
+ } break;
+
+ case Zone::IOControllers:
+ // TODO: have I overrestricted the value type for the IOC area?
+ ioc_.write(address, uint8_t(source));
+ return true;
+
+ case Zone::VideoController:
+ // TODO: handle byte writes correctly.
+ vidc_.write(source);
+ break;
+
+ case Zone::PhysicallyMappedRAM:
+ physical_ram<IntT>(address) = source;
+ return true;
+
+ case Zone::AddressTranslator:
+// printf("Translator write at %08x; replaces %08x\n", address, pages_[address & 0x7f]);
+ pages_[address & 0x7f] = address;
+ map_dirty_ = true;
+ break;
+
+ default:
+// printf("TODO: write of %08x to %08x [%lu]\n", source, address, sizeof(IntT));
+ break;
+ }
+
+ return true;
+ }
+
+ template <typename IntT>
+ bool read(uint32_t address, IntT &source, InstructionSet::ARM::Mode mode, bool) {
+ // User mode may only read logically-maped RAM and ROM.
+ if(mode == InstructionSet::ARM::Mode::User && address >= 0x200'0000 && address < 0x380'0000) {
+ return false;
+ }
+
+ switch (read_zones_[(address >> 21) & 31]) {
+ case Zone::PhysicallyMappedRAM:
+ source = physical_ram<IntT>(address);
+ return true;
+
+ case Zone::LogicallyMappedRAM: {
+ if(!has_moved_rom_) { // TODO: maintain this state in the zones table.
+ source = high_rom<IntT>(address);
+ return true;
+ }
+
+ const auto item = logical_ram<IntT, true>(address, mode);
+ if(!item) {
+ return false;
+ }
+ source = *item;
+ return true;
+ } break;
+
+ case Zone::LowROM:
+// logger.error().append("TODO: Low ROM read from %08x", address);
+ source = IntT(~0);
+ return true;
+
+ case Zone::HighROM:
+ // Real test is: require A24=A25=0, then A25=1.
+ // TODO: as above, move this test into the zones tables.
+ has_moved_rom_ = true;
+ source = high_rom<IntT>(address);
+ return true;
+
+ case Zone::IOControllers: {
+ if constexpr (std::is_same_v<IntT, uint8_t>) {
+ ioc_.read(address, source);
+ return true;
+ } else {
+ // TODO: generalise this adaptation of an 8-bit device to the 32-bit bus, which probably isn't right anyway.
+ uint8_t value;
+ ioc_.read(address, value);
+ source = value;
+ return true;
+ }
+ }
+
+ default:
+ logger.error().append("TODO: read from %08x", address);
+ break;
+ }
+
+ source = 0;
+ return false;
+ }
+
+ void tick_timers() { ioc_.tick_timers(); }
+ void tick_audio() {
+ // TODO: does disabling audio DMA pause output, or leave it ticking and merely
+ // stop allowing it to use the bus?
+ ioc_.sound().tick();
+ }
+
+ private:
+ Log::Logger<Log::Source::ARMIOC> logger;
+
+ enum class Zone {
+ LogicallyMappedRAM,
+ PhysicallyMappedRAM,
+ IOControllers,
+ LowROM,
+ HighROM,
+ VideoController,
+ DMAAndMEMC,
+ AddressTranslator,
+ };
+ static std::array<Zone, 0x20> zones(bool is_read) {
+ std::array<Zone, 0x20> zones{};
+ for(size_t c = 0; c < zones.size(); c++) {
+ const auto address = c << 21;
+ if(address < 0x200'0000) {
+ zones[c] = Zone::LogicallyMappedRAM;
+ } else if(address < 0x300'0000) {
+ zones[c] = Zone::PhysicallyMappedRAM;
+ } else if(address < 0x340'0000) {
+ zones[c] = Zone::IOControllers;
+ } else if(address < 0x360'0000) {
+ zones[c] = is_read ? Zone::LowROM : Zone::VideoController;
+ } else if(address < 0x380'0000) {
+ zones[c] = is_read ? Zone::LowROM : Zone::DMAAndMEMC;
+ } else {
+ zones[c] = is_read ? Zone::HighROM : Zone::AddressTranslator;
+ }
+ }
+ return zones;
+ }
+
+ bool has_moved_rom_ = false;
+ std::array<uint8_t, 4*1024*1024> ram_{};
+ std::array<uint8_t, 2*1024*1024> rom_;
+ InputOutputController<InterruptObserverT> ioc_;
+ Video vidc_;
+
+ template <typename IntT>
+ IntT &physical_ram(uint32_t address) {
+ address = aligned<IntT>(address);
+ address &= (ram_.size() - 1);
+ return *reinterpret_cast<IntT *>(&ram_[address]);
+ }
+
+ template <typename IntT>
+ IntT &high_rom(uint32_t address) {
+ address = aligned<IntT>(address);
+ return *reinterpret_cast<IntT *>(&rom_[address & (rom_.size() - 1)]);
+ }
+
+ const std::array<Zone, 0x20> read_zones_ = zones(true);
+ const std::array<Zone, 0x20> write_zones_ = zones(false);
+
+ // Control register values.
+ bool os_mode_ = false;
+ bool audio_dma_enable_ = false;
+ bool video_dma_enable_ = false; // "Unaffected" by reset, so here picked arbitrarily.
+
+ enum class DynamicRAMRefresh {
+ None = 0b00,
+ DuringFlyback = 0b01,
+ Continuous = 0b11,
+ } dynamic_ram_refresh_ = DynamicRAMRefresh::None; // State at reset is undefined; constrain to a valid enum value.
+
+ enum class ROMAccessTime {
+ ns450 = 0b00,
+ ns325 = 0b01,
+ ns200 = 0b10,
+ ns200with60nsNibble = 0b11,
+ } high_rom_access_time_ = ROMAccessTime::ns450, low_rom_access_time_ = ROMAccessTime::ns450;
+
+ enum class PageSize {
+ kb4 = 0b00,
+ kb8 = 0b01,
+ kb16 = 0b10,
+ kb32 = 0b11,
+ } page_size_ = PageSize::kb4;
+
+ // Address translator.
+ //
+ // MEMC contains one entry per a physical page number, indicating where it goes logically.
+ // Any logical access is tested against all 128 mappings. So that's backwards compared to
+ // the ideal for an emulator, which would map from logical to physical, even if a lot more
+ // compact — there are always 128 physical pages; there are up to 8192 logical pages.
+ //
+ // So captured here are both the physical -> logical map as representative of the real
+ // hardware, and the reverse logical -> physical map, which is built (and rebuilt, and rebuilt)
+ // from the other.
+
+ // Physical to logical mapping.
+ std::array<uint32_t, 128> pages_{};
+
+ // Logical to physical mapping.
+ struct MappedPage {
+ uint8_t *target = nullptr;
+ uint8_t protection_level = 0;
+ };
+ std::array<MappedPage, 8192> mapping_;
+ bool map_dirty_ = true;
+
+ template <typename IntT, bool is_read>
+ IntT *logical_ram(uint32_t address, InstructionSet::ARM::Mode mode) {
+ // Possibly TODO: this recompute-if-dirty flag is supposed to ameliorate for an expensive
+ // mapping process. It can be eliminated when the process is improved.
+ if(map_dirty_) {
+ update_mapping();
+ map_dirty_ = false;
+ }
+
+ address = aligned<IntT>(address);
+ address &= 0x1ff'ffff;
+ size_t page;
+
+ // TODO: eliminate switch here.
+ switch(page_size_) {
+ default:
+ case PageSize::kb4:
+ page = address >> 12;
+ address &= 0x0fff;
+ break;
+ case PageSize::kb8:
+ page = address >> 13;
+ address &= 0x1fff;
+ break;
+ case PageSize::kb16:
+ page = address >> 14;
+ address &= 0x3fff;
+ break;
+ case PageSize::kb32:
+ page = address >> 15;
+ address &= 0x7fff;
+ break;
+ }
+
+ if(!mapping_[page].target) {
+ return nullptr;
+ }
+
+ // TODO: eliminate switch here.
+ // Top of my head idea: is_read, is_user and is_os_mode make three bits, so
+ // keep a one-byte bitmap of permitted accesses rather than the raw protection
+ // level?
+ switch(mapping_[page].protection_level) {
+ case 0b00: break;
+ case 0b01:
+ if(!is_read && mode == InstructionSet::ARM::Mode::User) {
+ return nullptr;
+ }
+ break;
+ default:
+ if(mode == InstructionSet::ARM::Mode::User) {
+ return nullptr;
+ }
+ if(!is_read && !os_mode_) {
+ return nullptr;
+ }
+ break;
+ }
+
+ return reinterpret_cast<IntT *>(mapping_[page].target + address);
+ }
+
+ void update_mapping() {
+ // For each physical page, project it into logical space.
+ switch(page_size_) {
+ default:
+ case PageSize::kb4: update_mapping<PageSize::kb4>(); break;
+ case PageSize::kb8: update_mapping<PageSize::kb8>(); break;
+ case PageSize::kb16: update_mapping<PageSize::kb16>(); break;
+ case PageSize::kb32: update_mapping<PageSize::kb32>(); break;
+ }
+ }
+
+ template <PageSize size>
+ void update_mapping() {
+ // Clear all logical mappings.
+ std::fill(mapping_.begin(), mapping_.end(), MappedPage{});
+
+ // For each physical page, project it into logical space
+ // and store it.
+ for(const auto page: pages_) {
+ uint32_t physical, logical;
+
+ switch(size) {
+ case PageSize::kb4:
+ // 4kb:
+ // A[6:0] -> PPN[6:0]
+ // A[11:10] -> LPN[12:11]; A[22:12] -> LPN[10:0] i.e. 8192 logical pages
+ physical = page & BitMask<6, 0>::value;
+
+ physical <<= 12;
+
+ logical = (page & BitMask<11, 10>::value) << 1;
+ logical |= (page & BitMask<22, 12>::value) >> 12;
+ break;
+
+ case PageSize::kb8:
+ // 8kb:
+ // A[0] -> PPN[6]; A[6:1] -> PPN[5:0]
+ // A[11:10] -> LPN[11:10]; A[22:13] -> LPN[9:0] i.e. 4096 logical pages
+ physical = (page & BitMask<0, 0>::value) << 6;
+ physical |= (page & BitMask<6, 1>::value) >> 1;
+
+ physical <<= 13;
+
+ logical = page & BitMask<11, 10>::value;
+ logical |= (page & BitMask<22, 13>::value) >> 13;
+ break;
+
+ case PageSize::kb16:
+ // 16kb:
+ // A[1:0] -> PPN[6:5]; A[6:2] -> PPN[4:0]
+ // A[11:10] -> LPN[10:9]; A[22:14] -> LPN[8:0] i.e. 2048 logical pages
+ physical = (page & BitMask<1, 0>::value) << 5;
+ physical |= (page & BitMask<6, 2>::value) >> 2;
+
+ physical <<= 14;
+
+ logical = (page & BitMask<11, 10>::value) >> 1;
+ logical |= (page & BitMask<22, 14>::value) >> 14;
+ break;
+
+ case PageSize::kb32:
+ // 32kb:
+ // A[1] -> PPN[6]; A[2] -> PPN[5]; A[0] -> PPN[4]; A[6:3] -> PPN[3:0]
+ // A[11:10] -> LPN[9:8]; A[22:15] -> LPN[7:0] i.e. 1024 logical pages
+ physical = (page & BitMask<1, 1>::value) << 5;
+ physical |= (page & BitMask<2, 2>::value) << 3;
+ physical |= (page & BitMask<0, 0>::value) << 4;
+ physical |= (page & BitMask<6, 3>::value) >> 3;
+
+ physical <<= 15;
+
+ logical = (page & BitMask<11, 10>::value) >> 2;
+ logical |= (page & BitMask<22, 15>::value) >> 15;
+ break;
+ }
+
+// printf("%08x => physical %d -> logical %d\n", page, (physical >> 15), logical);
+
+ // TODO: consider clashes.
+ // TODO: what if there's less than 4mb present?
+ mapping_[logical].target = &ram_[physical];
+ mapping_[logical].protection_level = (page >> 8) & 3;
+ }
+ }
+};
+
+}
diff --git a/Machines/Acorn/Archimedes/Sound.hpp b/Machines/Acorn/Archimedes/Sound.hpp
new file mode 100644
index 000000000..aad9bd1f0
--- /dev/null
+++ b/Machines/Acorn/Archimedes/Sound.hpp
@@ -0,0 +1,69 @@
+//
+// Audio.hpp
+// Clock Signal
+//
+// Created by Thomas Harte on 20/03/2024.
+// Copyright © 2024 Thomas Harte. All rights reserved.
+//
+
+#pragma once
+
+namespace Archimedes {
+
+template <typename InterruptObserverT>
+struct Sound {
+ Sound(InterruptObserverT &observer) : observer_(observer) {}
+
+ void set_next_end(uint32_t value) {
+ next_.end = value;
+ }
+
+ void set_next_start(uint32_t value) {
+ next_.start = value;
+ set_buffer_valid(true); // My guess: this is triggered on next buffer start write.
+ }
+
+ bool interrupt() const {
+ return !next_buffer_valid_;
+ }
+
+ void swap() {
+ current_.start = next_.start;
+ std::swap(current_.end, next_.end);
+ set_buffer_valid(false);
+ halted_ = false;
+ }
+
+ void tick() {
+ if(halted_) {
+ return;
+ }
+
+ current_.start += 16;
+ if(current_.start == current_.end) {
+ if(next_buffer_valid_) {
+ swap();
+ } else {
+ halted_ = true;
+ }
+ }
+ }
+
+private:
+ void set_buffer_valid(bool valid) {
+ next_buffer_valid_ = valid;
+ observer_.update_sound_interrupt();
+ }
+
+ bool next_buffer_valid_ = false;
+ bool halted_ = true; // This is a bit of a guess.
+
+ struct Buffer {
+ uint32_t start = 0, end = 0;
+ };
+ Buffer current_, next_;
+
+ InterruptObserverT &observer_;
+};
+
+}
diff --git a/Machines/Acorn/Archimedes/Video.hpp b/Machines/Acorn/Archimedes/Video.hpp
new file mode 100644
index 000000000..3a69d0c03
--- /dev/null
+++ b/Machines/Acorn/Archimedes/Video.hpp
@@ -0,0 +1,110 @@
+//
+// Video.hpp
+// Clock Signal
+//
+// Created by Thomas Harte on 20/03/2024.
+// Copyright © 2024 Thomas Harte. All rights reserved.
+//
+
+#pragma once
+
+#include "../../../Outputs/Log.hpp"
+
+#include <cstdint>
+
+namespace Archimedes {
+
+struct Video {
+ void write(uint32_t value) {
+ const auto target = (value >> 24) & 0xfc;
+
+ switch(target) {
+ case 0x00: case 0x04: case 0x08: case 0x0c:
+ case 0x10: case 0x14: case 0x18: case 0x1c:
+ case 0x20: case 0x24: case 0x28: case 0x2c:
+ case 0x30: case 0x34: case 0x38: case 0x3c:
+ logger.error().append("TODO: Video palette logical colour %d to %03x", (target >> 2), value & 0x1fff);
+ break;
+
+ case 0x40:
+ logger.error().append("TODO: Video border colour to %03x", value & 0x1fff);
+ break;
+
+ case 0x44: case 0x48: case 0x4c:
+ logger.error().append("TODO: Cursor colour %d to %03x", (target - 0x44) >> 2, value & 0x1fff);
+ break;
+
+ case 0x60: case 0x64: case 0x68: case 0x6c:
+ case 0x70: case 0x74: case 0x78: case 0x7c:
+ logger.error().append("TODO: Stereo image register %d to %03x", (target - 0x60) >> 2, value & 0x7);
+ break;
+
+ case 0x80:
+ logger.error().append("TODO: Video horizontal period: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0x84:
+ logger.error().append("TODO: Video horizontal sync width: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0x88:
+ logger.error().append("TODO: Video horizontal border start: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0x8c:
+ logger.error().append("TODO: Video horizontal display start: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0x90:
+ logger.error().append("TODO: Video horizontal display end: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0x94:
+ logger.error().append("TODO: Video horizontal border end: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0x98:
+ logger.error().append("TODO: Video horizontal cursor end: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0x9c:
+ logger.error().append("TODO: Video horizontal interlace: %d", (value >> 14) & 0x3ff);
+ break;
+
+ case 0xa0:
+ logger.error().append("TODO: Video vertical period: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0xa4:
+ logger.error().append("TODO: Video vertical sync width: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0xa8:
+ logger.error().append("TODO: Video vertical border start: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0xac:
+ logger.error().append("TODO: Video vertical display start: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0xb0:
+ logger.error().append("TODO: Video vertical display end: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0xb4:
+ logger.error().append("TODO: Video vertical border end: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0xb8:
+ logger.error().append("TODO: Video vertical cursor start: %d", (value >> 14) & 0x3ff);
+ break;
+ case 0xbc:
+ logger.error().append("TODO: Video vertical cursor end: %d", (value >> 14) & 0x3ff);
+ break;
+
+ case 0xc0:
+ logger.error().append("TODO: Sound frequency: %d", value & 0x7f);
+ break;
+
+ case 0xe0:
+ logger.error().append("TODO: video control: %08x", value);
+ break;
+
+ default:
+ logger.error().append("TODO: unrecognised VIDC write of %08x", value);
+ break;
+ }
+ }
+
+private:
+ Log::Logger<Log::Source::ARMIOC> logger;
+};
+
+}
diff --git a/OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj b/OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj
index f74c8fc91..54a36d96d 100644
--- a/OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj
+++ b/OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj
@@ -1808,6 +1808,13 @@
4BA9C3CF1D8164A9002DDB61 /* MediaTarget.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = MediaTarget.hpp; sourceTree = "<group>"; };
4BAA167B21582B1D008A3276 /* Target.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = Target.hpp; sourceTree = "<group>"; };
4BAB1E522BA9D9950002C9B9 /* Disassembler.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = Disassembler.hpp; sourceTree = "<group>"; };
+ 4BAB1E532BAB5B040002C9B9 /* Sound.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = Sound.hpp; sourceTree = "<group>"; };
+ 4BAB1E542BAB5B3F0002C9B9 /* Keyboard.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = Keyboard.hpp; sourceTree = "<group>"; };
+ 4BAB1E552BAB5B6D0002C9B9 /* HalfDuplexSerial.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = HalfDuplexSerial.hpp; sourceTree = "<group>"; };
+ 4BAB1E562BAB5BC60002C9B9 /* Video.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = Video.hpp; sourceTree = "<group>"; };
+ 4BAB1E582BAB5C210002C9B9 /* MemoryController.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = MemoryController.hpp; sourceTree = "<group>"; };
+ 4BAB1E592BAB5CB90002C9B9 /* CMOSRAM.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = CMOSRAM.hpp; sourceTree = "<group>"; };
+ 4BAB1E5A2BAB5F400002C9B9 /* InputOutputController.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = InputOutputController.hpp; sourceTree = "<group>"; };
4BAB62AC1D3272D200DF5BA0 /* Disk.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = Disk.hpp; sourceTree = "<group>"; };
4BAB62AE1D32730D00DF5BA0 /* Storage.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = Storage.hpp; sourceTree = "<group>"; };
4BAF2B4C2004580C00480230 /* DMK.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = DMK.cpp; sourceTree = "<group>"; };
@@ -4394,6 +4401,13 @@
children = (
4BB505842B9634F30031C43C /* Archimedes.cpp */,
4BB505852B9634F30031C43C /* Archimedes.hpp */,
+ 4BAB1E592BAB5CB90002C9B9 /* CMOSRAM.hpp */,
+ 4BAB1E552BAB5B6D0002C9B9 /* HalfDuplexSerial.hpp */,
+ 4BAB1E5A2BAB5F400002C9B9 /* InputOutputController.hpp */,
+ 4BAB1E542BAB5B3F0002C9B9 /* Keyboard.hpp */,
+ 4BAB1E582BAB5C210002C9B9 /* MemoryController.hpp */,
+ 4BAB1E532BAB5B040002C9B9 /* Sound.hpp */,
+ 4BAB1E562BAB5BC60002C9B9 /* Video.hpp */,
);
path = Archimedes;
sourceTree = "<group>";
diff --git a/Outputs/Log.hpp b/Outputs/Log.hpp
index a0827d4fa..22b02f8d0 100644
--- a/Outputs/Log.hpp
+++ b/Outputs/Log.hpp
@@ -25,6 +25,9 @@ enum class Source {
AmigaBlitter,
AppleIISCSICard,
Archimedes,
+ ARMIOC,
+ ARMMEMC,
+ ARMVIDC,
AtariST,
AtariSTDMAController,
CommodoreStaticAnalyser,
@@ -90,6 +93,9 @@ constexpr const char *prefix(Source source) {
case Source::AmigaDisk: return "Disk";
case Source::AppleIISCSICard: return "SCSI card";
case Source::Archimedes: return "Archimedes";
+ case Source::ARMIOC: return "IOC";
+ case Source::ARMMEMC: return "MEMC";
+ case Source::ARMVIDC: return "VIDC";
case Source::AtariST: return "AtariST";
case Source::AtariSTDMAController: return "DMA";
case Source::CommodoreStaticAnalyser: return "Commodore Static Analyser";