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Merge pull request #1238 from TomHarte/MissingIncludes

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Add 6845/MDA cursor.
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Thomas Harte 2023-12-04 10:36:44 -05:00 committed by GitHub
commit 9b23984d35
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4 changed files with 54 additions and 20 deletions
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47
Components/6845/CRTC6845.hpp
View File

@ -50,9 +50,22 @@ enum Personality {
AMS40226 // Type 3. Status is get register, fixed-length VSYNC, no zero-length HSYNC.
};
// https://www.pcjs.org/blog/2018/03/20/ advises that "the behavior of bits 5 and 6 [of register 10, the cursor start
// register is really card specific".
//
// This enum captures those specifics.
enum CursorType {
/// No cursor signal is generated.
None,
/// MDA style: 00 => symmetric blinking; 01 or 10 => no blinking; 11 => short on, long off.
MDA,
/// EGA style: ignore the bits completely.
EGA,
};
// TODO UM6845R and R12/R13; see http://www.cpcwiki.eu/index.php/CRTC#CRTC_Differences
template <class T> class CRTC6845 {
template <class T, CursorType cursor_type> class CRTC6845 {
public:
CRTC6845(Personality p, T &bus_handler) noexcept :
@ -123,7 +136,7 @@ template <class T> class CRTC6845 {
bus_state_.refresh_address = (bus_state_.refresh_address + 1) & 0x3fff;
bus_state_.cursor = is_cursor_line_ &&
bus_state_.refresh_address == ((registers_[15] | (registers_[14] << 8))&0x3fff);
bus_state_.refresh_address == (registers_[15] | (registers_[14] << 8));
// Check for end-of-line.
if(character_counter_ == registers_[0]) {
@ -179,9 +192,11 @@ template <class T> class CRTC6845 {
}
inline void do_end_of_line() {
// Check for cursor disable.
// TODO: this is handled differently on the EGA, should I ever implement that.
is_cursor_line_ &= bus_state_.row_address != (registers_[11] & 0x1f);
if constexpr (cursor_type != CursorType::None) {
// Check for cursor disable.
// TODO: this is handled differently on the EGA, should I ever implement that.
is_cursor_line_ &= bus_state_.row_address != (registers_[11] & 0x1f);
}
// Check for end of vertical sync.
if(bus_state_.vsync) {
@ -242,8 +257,21 @@ template <class T> class CRTC6845 {
character_counter_ = 0;
character_is_visible_ = (registers_[1] != 0);
// Check for cursor enable.
is_cursor_line_ |= bus_state_.row_address == (registers_[10] & 0x1f);
if constexpr (cursor_type != CursorType::None) {
// Check for cursor enable.
is_cursor_line_ |= bus_state_.row_address == (registers_[10] & 0x1f);
switch(cursor_type) {
// MDA-style blinking; timings are a bit of a guess for now.
case CursorType::MDA:
switch(registers_[10] >> 5) {
case 0b11: is_cursor_line_ &= (field_count_ & 15) < 5; break;
case 0b00: is_cursor_line_ &= bool(field_count_ & 16); break;
default: break;
}
break;
}
}
}
inline void do_end_of_frame() {
@ -251,6 +279,9 @@ template <class T> class CRTC6845 {
line_is_visible_ = true;
line_address_ = uint16_t((registers_[12] << 8) | registers_[13]);
bus_state_.refresh_address = line_address_;
if constexpr (cursor_type != CursorType::None) {
++field_count_;
}
}
Personality personality_;
@ -278,6 +309,8 @@ template <class T> class CRTC6845 {
unsigned int character_is_visible_shifter_ = 0;
bool is_cursor_line_ = false;
int field_count_ = 0;
};
}

2
Concurrency/AsyncTaskQueue.hpp
View File

@ -128,7 +128,7 @@ template <bool perform_automatically, bool start_immediately = true, typename Pe
while(!should_quit_) {
// Wait for new actions to be signalled, and grab them.
std::unique_lock lock(condition_mutex_);
while(actions_.empty()) {
while(actions_.empty() && !should_quit_) {
condition_.wait(lock);
}
std::swap(actions, actions_);

7
Machines/AmstradCPC/AmstradCPC.cpp
View File

@ -585,6 +585,7 @@ class CRTCBusHandler {
InterruptTimer &interrupt_timer_;
};
using CRTC = Motorola::CRTC::CRTC6845<CRTCBusHandler, Motorola::CRTC::CursorType::None>;
/*!
Holds and vends the current keyboard state, acting as the AY's port handler.
@ -683,7 +684,7 @@ class i8255PortHandler : public Intel::i8255::PortHandler {
public:
i8255PortHandler(
KeyboardState &key_state,
const Motorola::CRTC::CRTC6845<CRTCBusHandler> &crtc,
const CRTC &crtc,
AYDeferrer &ay,
Storage::Tape::BinaryTapePlayer &tape_player) :
ay_(ay),
@ -742,7 +743,7 @@ class i8255PortHandler : public Intel::i8255::PortHandler {
private:
AYDeferrer &ay_;
const Motorola::CRTC::CRTC6845<CRTCBusHandler> &crtc_;
const CRTC &crtc_;
KeyboardState &key_state_;
Storage::Tape::BinaryTapePlayer &tape_player_;
};
@ -1219,7 +1220,7 @@ template <bool has_fdc> class ConcreteMachine:
CPU::Z80::Processor<ConcreteMachine, false, true> z80_;
CRTCBusHandler crtc_bus_handler_;
Motorola::CRTC::CRTC6845<CRTCBusHandler> crtc_;
CRTC crtc_;
AYDeferrer ay_;
i8255PortHandler i8255_port_handler_;

18
Machines/PCCompatible/PCCompatible.cpp
View File

@ -625,7 +625,7 @@ class MDA {
const uint8_t *ram = nullptr;
std::vector<uint8_t> font;
} outputter_;
Motorola::CRTC::CRTC6845<CRTCOutputter> crtc_;
Motorola::CRTC::CRTC6845<CRTCOutputter, Motorola::CRTC::CursorType::MDA> crtc_;
int full_clock_;
};
@ -885,14 +885,14 @@ class IO {
printf("Unhandled in: %04x\n", port);
break;
case 0x0000: return dma_.controller.read<0>();
case 0x0001: return dma_.controller.read<1>();
case 0x0002: return dma_.controller.read<2>();
case 0x0003: return dma_.controller.read<3>();
case 0x0004: return dma_.controller.read<4>();
case 0x0005: return dma_.controller.read<5>();
case 0x0006: return dma_.controller.read<6>();
case 0x0007: return dma_.controller.read<7>();
case 0x0000: return dma_.controller.template read<0>();
case 0x0001: return dma_.controller.template read<1>();
case 0x0002: return dma_.controller.template read<2>();
case 0x0003: return dma_.controller.template read<3>();
case 0x0004: return dma_.controller.template read<4>();
case 0x0005: return dma_.controller.template read<5>();
case 0x0006: return dma_.controller.template read<6>();
case 0x0007: return dma_.controller.template read<7>();
case 0x0008: return dma_.controller.status();