Improve timing

Author: drhelius

platforms/shared/desktop/mcp/mcp_debug_adapter.cpp

@@ -148,7 +148,7 @@ void DebugAdapter::ClearBreakpointByAddress(u16 address, u16 end_address)
     {
         M6502::GLYNX_Breakpoint& bp = (*breakpoints)[i];
 
-        if (end_address > 0 && end_address > address)
+        if (end_address > 0 && end_address >= address)
         {
             if (bp.range && bp.address1 == address && bp.address2 == end_address)
                 breakpoints->erase(breakpoints->begin() + i);
@@ -613,6 +613,10 @@ json DebugAdapter::Get6502Status()
     // CPU IRQ line status
     status["IRQ_line_asserted"] = cpu->irq_asserted;
 
+    // Last instruction ticks
+    status["last_ticks"] = cpu->last_ticks;
+    status["total_ticks"] = cpu->total_ticks;
+
     return status;
 }
 

src/bus.h

@@ -36,13 +36,13 @@ class Bus
     u32 m_cycles;
 };
 
-static const u32 k_bus_cycles_suzy_read         = 7;    // Suzy register read (9-15 ticks, base 5 + 4-10 extra)
-static const u32 k_bus_cycles_suzy_write        = 0;    // Suzy register write (blind write, 5 ticks)
+static const u32 k_bus_cycles_suzy_read         = 3;    // Suzy register read
+static const u32 k_bus_cycles_suzy_write        = 0;    // Suzy register write
 static const u32 k_bus_cycles_cart_read         = 3;    // Cart read
 static const u32 k_bus_cycles_mikey_read        = 0;    // Mikey register read
 static const u32 k_bus_cycles_mikey_write       = 0;    // Mikey register write
 static const u32 k_bus_cycles_int_tick_factor   = 5;    // Internal CPU cycle to tick scaling
-static const u32 k_bus_cycles_timer             = 2;
+static const u32 k_bus_cycles_timer             = 7;
 static const u32 k_bus_cycles_audio             = 7;
 
 #endif /* BUS_H */

src/defines.h

@@ -51,7 +51,7 @@
 
 #define GLYNX_BIOS_SIZE 0x200
 
-#define GLYNX_SAVESTATE_VERSION 6
+#define GLYNX_SAVESTATE_VERSION 7
 #define GLYNX_SAVESTATE_MAGIC 0x56191212
 
 #if !defined(NULL)

src/lcd_screen.cpp

@@ -50,21 +50,19 @@ void LcdScreen::Reset()
     memset(m_screen_buffer, 0, sizeof(m_screen_buffer));
     memset(m_current_palette, 0, sizeof(m_current_palette));
     memset(m_dma_buffer, 0, sizeof(m_dma_buffer));
-
     m_current_cycle = 0;
     m_current_line = 0;
     m_rendering_offset = 80;
     m_line_cycles = 0;
-
     m_dma_next_at = 0;
     m_dma_current_src_addr = 0;
     m_dma_burst_count = 0;
     m_dma_buffer_half = 0;
-
     m_pixel_next_at = 0;
     m_pixel_count = 0;
     m_pixel_buffer_read_pos = 0;
     m_line_dst_offset = 0;
+    m_in_vblank = false;
 }
 
 void LcdScreen::InitPalettes()
@@ -208,4 +206,5 @@ void LcdScreen::Serialize(StateSerializer& s)
     G_SERIALIZE(s, m_pixel_count);
     G_SERIALIZE(s, m_pixel_buffer_read_pos);
     G_SERIALIZE(s, m_line_dst_offset);
+    G_SERIALIZE(s, m_in_vblank);
 }

src/lcd_screen.h

@@ -38,6 +38,7 @@ class LcdScreen
     void Reset();
     void Update(u32 cycles);
     void ResetLine(u8 line);
+    void ClearLine(u8 line);
     void FirstDMA();
     void ConfigureLineTiming();
     void UpdatePalette(int index, u16 color);
@@ -48,6 +49,7 @@ class LcdScreen
     u16* GetRGB565Palette();
     GLYNX_Pixel_Format GetPixelFormat();
     void RenderNoBiosScreen(u8* frame_buffer);
+    void SetVBlank(bool vblank);
     void SaveState(std::ostream& stream);
     void LoadState(std::istream& stream);
 
@@ -80,6 +82,7 @@ class LcdScreen
     u32 m_pixel_count;
     u32 m_pixel_buffer_read_pos;
     u32 m_line_dst_offset;
+    bool m_in_vblank;
     GLYNX_Pixel_Format m_pixel_format;
     u32 m_rgba8888_palette[4096] = {};
     u16 m_rgb565_palette[4096] = {};

src/lcd_screen_inline.h

@@ -27,6 +27,9 @@
 
 INLINE void LcdScreen::Update(u32 cycles)
 {
+    if (m_in_vblank)
+        return;
+
     m_current_cycle += cycles;
 
     if (m_dma_burst_count >= k_dma_bursts_per_line && m_pixel_count >= GLYNX_SCREEN_WIDTH)
@@ -59,6 +62,12 @@ INLINE void LcdScreen::ResetLine(u8 line)
     m_line_dst_offset = m_current_line * GLYNX_SCREEN_WIDTH;
 }
 
+INLINE void LcdScreen::ClearLine(u8 line)
+{
+    u32 offset = line * GLYNX_SCREEN_WIDTH;
+    memset(&m_screen_buffer[offset], 0, GLYNX_SCREEN_WIDTH * sizeof(u16));
+}
+
 INLINE void LcdScreen::FirstDMA()
 {
     m_dma_current_src_addr = m_mikey->GetState()->dispadr_latch;
@@ -107,6 +116,11 @@ INLINE GLYNX_Pixel_Format LcdScreen::GetPixelFormat()
     return m_pixel_format;
 }
 
+INLINE void LcdScreen::SetVBlank(bool vblank)
+{
+    m_in_vblank = vblank;
+}
+
 INLINE void LcdScreen::DoDMA()
 {
     u8* dst = &m_dma_buffer[m_dma_buffer_half];

src/m6502.cpp

@@ -39,6 +39,10 @@ M6502::M6502(Bus* bus)
     m_s.debug_next_irq = 0;
     m_s.debug_irq_mask = 0;
     m_s.halted = false;
+    m_s.onebyte_un_nop = false;
+    m_s.page_mode_discounts = 0;
+    m_s.last_ticks = 0;
+    m_s.total_ticks = 0;
     m_breakpoints_enabled = false;
     m_breakpoints_irq_enabled = 0;
     m_cpu_breakpoint_hit = false;
@@ -48,6 +52,8 @@ M6502::M6502(Bus* bus)
     m_disassembler_call_stack_size = 0;
     m_reset_value = -1;
     m_prev_opcode_address = 0xFFFF;
+    m_stream_open = false;
+    m_page_mode_tick_discount = 0;
 }
 
 M6502::~M6502()
@@ -93,11 +99,17 @@ void M6502::Reset()
     m_s.irq_pending = 0;
     m_s.debug_irq_mask = 0;
     m_s.halted = false;
+    m_s.onebyte_un_nop = false;
+    m_s.page_mode_discounts = 0;
+    m_s.last_ticks = 0;
+    m_s.total_ticks = 0;
     m_cpu_breakpoint_hit = false;
     m_memory_breakpoint_hit = false;
     m_run_to_breakpoint_hit = false;
     m_run_to_breakpoint_requested = false;
     m_prev_opcode_address = 0xFFFF;
+    m_stream_open = false;
+    m_page_mode_tick_discount = 0;
     ClearDisassemblerCallStack();
 }
 
@@ -344,4 +356,8 @@ void M6502::Serialize(StateSerializer& s)
     G_SERIALIZE(s, m_s.debug_next_irq);
     G_SERIALIZE(s, m_s.debug_irq_mask);
     G_SERIALIZE(s, m_s.halted);
+    G_SERIALIZE(s, m_s.onebyte_un_nop);
+    G_SERIALIZE(s, m_s.page_mode_discounts);
+    G_SERIALIZE(s, m_stream_open);
+    G_SERIALIZE(s, m_page_mode_tick_discount);
 }

src/m6502.h

@@ -62,6 +62,9 @@ class M6502
         s32 debug_irq_mask;
         bool halted;
         bool onebyte_un_nop;
+        u8 page_mode_discounts;
+        u32 last_ticks;
+        u64 total_ticks;
     };
 
     struct GLYNX_Breakpoint
@@ -108,6 +111,7 @@ class M6502
     void ClearDisassemblerCallStack();
     std::stack<GLYNX_CallStackEntry>* GetDisassemblerCallStack();
     void CheckMemoryBreakpoints(u16 address, bool read);
+    void SetPageModeEnabled(bool enabled);
     void SaveState(std::ostream& stream);
     void LoadState(std::istream& stream);
 
@@ -129,7 +133,9 @@ class M6502
     std::stack<GLYNX_CallStackEntry> m_disassembler_call_stack;
     int m_disassembler_call_stack_size;
     int m_reset_value;
+    bool m_stream_open;
     u16 m_prev_opcode_address;
+    u8 m_page_mode_tick_discount;
 
 private:
     void HandleIRQ();
@@ -139,8 +145,12 @@ class M6502
     void PushCallStack(u16 src, u16 dest, u16 back);
     void PopCallStack();
 
-    u8 Fetch8();
-    u16 Fetch16();
+    u8 FetchOpcode8();
+    u8 FetchOperand8();
+    u16 FetchOperand16();
+    void NotifyBusBreak();
+    u8 MemRead8(u16 address);
+    void MemWrite8(u16 address, u8 value);
     u16 Address16(u8 high, u8 low);
     bool PageCrossed(u16 old_address, u16 new_address);
     u16 ZeroPageX();