Eliminate phases due to lack of evidence.

Components/6845/CRTC6845.hpp

@@ -30,19 +30,7 @@ struct BusState {
 
 class BusHandler {
 	public:
-		/*!
+		void perform_bus_cycle(const BusState &) {}
-			Performs the first phase of a 6845 bus cycle; this is the phase in which it is intended that
-			systems using the 6845 respect the bus state and produce pixels, sync or whatever they require.
-		*/
-		void perform_bus_cycle_phase1(const BusState &) {}
-
-		/*!
-			Performs the second phase of a 6845 bus cycle. Some bus state, including sync, is updated
-			directly after phase 1 and hence is visible to an observer during phase 2. Handlers may therefore
-			implement @c perform_bus_cycle_phase2 to be notified of the availability of that state without
-			having to wait until the next cycle has begun.
-		*/
-		void perform_bus_cycle_phase2(const BusState &) {}
 };
 
 enum class Personality {
@@ -196,10 +184,7 @@ template <class BusHandlerT, Personality personality, CursorType cursor_type> cl
 				bus_state_.cursor = is_cursor_line_ &&
 					bus_state_.refresh_address == layout_.cursor_address;
 				bus_state_.display_enable = character_is_visible_ && line_is_visible_;
-
+				bus_handler_.perform_bus_cycle(bus_state_);
-				// TODO: considate the two below.
-				perform_bus_cycle_phase1();
-				perform_bus_cycle_phase2();
 
 				//
 				// Shared, stateless signals.
@@ -212,7 +197,7 @@ template <class BusHandlerT, Personality personality, CursorType cursor_type> cl
 						character_total_hit && was_eof &&
 						(
 							layout_.interlace_mode_ == InterlaceMode::Off ||
-							!(bus_state_.field_count&1)
+							!odd_field_
 						);
 
 				//
@@ -373,17 +358,6 @@ template <class BusHandlerT, Personality personality, CursorType cursor_type> cl
 	private:
 		static constexpr uint16_t RefreshMask = (personality >= Personality::EGA) ? 0xffff : 0x3fff;
 
-		inline void perform_bus_cycle_phase1() {
-			// Skew theory of operation: keep a history of the last three states, and apply whichever is selected.
-//			character_is_visible_shifter_ = (character_is_visible_shifter_ << 1) | unsigned(character_is_visible_);
-//			bus_state_.display_enable = (int(character_is_visible_shifter_) & display_skew_mask_) && line_is_visible_;
-			bus_handler_.perform_bus_cycle_phase1(bus_state_);
-		}
-
-		inline void perform_bus_cycle_phase2() {
-			bus_handler_.perform_bus_cycle_phase2(bus_state_);
-		}
-
 		BusHandlerT &bus_handler_;
 		BusState bus_state_;
 

Machines/AmstradCPC/AmstradCPC.cpp

@@ -189,7 +189,7 @@ class CRTCBusHandler {
 			The CRTC entry function for the main part of each clock cycle; takes the current
 			bus state and determines what output to produce based on the current palette and mode.
 		*/
-		forceinline void perform_bus_cycle_phase1(const Motorola::CRTC::BusState &state) {
+		forceinline void perform_bus_cycle(const Motorola::CRTC::BusState &state) {
 			// The gate array waits 2us to react to the CRTC's vsync signal, and then
 			// caps output at 4us. Since the clock rate is 1Mhz, that's 2 and 4 cycles,
 			// respectively.
@@ -299,13 +299,7 @@ class CRTCBusHandler {
 					}
 				}
 			}
-		}
 
-		/*!
-			The CRTC entry function for phase 2 of each bus cycle, in which the next sync line state becomes
-			visible early. The CPC uses changes in sync to clock the interrupt timer.
-		*/
-		void perform_bus_cycle_phase2(const Motorola::CRTC::BusState &state) {
 			// Notify a leading hsync edge to the interrupt timer.
 			// Per Interrupts in the CPC: "to be confirmed: does gate array count positive or negative edge transitions of HSYNC signal?";
 			// if you take it as given that display mode is latched as a result of hsync then Pipe Mania seems to imply that the count

Machines/PCCompatible/CGA.hpp

@@ -173,7 +173,7 @@ class CGA {
 				return new_state;
 			}
 
-			void perform_bus_cycle_phase1(const Motorola::CRTC::BusState &state) {
+			void perform_bus_cycle(const Motorola::CRTC::BusState &state) {
 				// Determine new output state.
 				update_hsync(state.hsync);
 				const OutputState new_state = implied_state(state);
@@ -246,7 +246,6 @@ class CGA {
 					count = 0;
 				}
 			}
-			void perform_bus_cycle_phase2(const Motorola::CRTC::BusState &) {}
 
 			void flush_pixels() {
 				crt.output_data(count * active_clock_divider, size_t((count * active_pixels_per_tick) / 8));

Machines/PCCompatible/MDA.hpp

@@ -104,7 +104,7 @@ class MDA {
 				return control_;
 			}
 
-			void perform_bus_cycle_phase1(const Motorola::CRTC::BusState &state) {
+			void perform_bus_cycle(const Motorola::CRTC::BusState &state) {
 				// Determine new output state.
 				const OutputState new_state =
 					(state.hsync | state.vsync) ? OutputState::Sync :
@@ -207,7 +207,6 @@ class MDA {
 					pixels = pixel_pointer = nullptr;
 				}
 			}
-			void perform_bus_cycle_phase2(const Motorola::CRTC::BusState &) {}
 
 			Outputs::CRT::CRT crt;