Sync push

extra/config/testMachine.dvm

@@ -7,7 +7,7 @@ fixed_clock = false
 clock_rate_sec = 5000
 memory_extension_pages = 16
 
-screen_redraw_rate_per_second = 20
+screen_redraw_rate_per_second = 10
 
 SingleColor_foreground = #009900FF
 SingleColor_background = #111111FF

extra/dss/bios/data.dss

@@ -66,6 +66,8 @@
 	TEXT_SIGNLE_INVERT						{ MemoryAddresses.VGA + 0x0005 }
 	TEXT_SIGNLE_STR							{ MemoryAddresses.VGA + 0x0006 }
 
+	FLAGS									{ MemoryAddresses.VGA + 0x007E }
+
 	MEMORY_CONTROLLER_X						{ MemoryAddresses.VGA + 0x0080 }
 	MEMORY_CONTROLLER_X_BYTE				{ MemoryAddresses.VGA + 0x0080 + 1 }
 	MEMORY_CONTROLLER_Y						{ MemoryAddresses.VGA + 0x0082 }
@@ -116,6 +118,7 @@
 
 	REFRESH_SCREEN 		0xE0
 	CLEAR_SCREEN 		0xE1
+	REDRAW_SCREEN 		0xE2
 @end
 @raw_export_end
 @export_comment BIOS_API " --\n"
@@ -127,10 +130,12 @@
 @group Sig_VGA_Text_16_Color
 	CONTINUE 					0x00
 
+	SWAP_BUFFERS				0x10
 	WRITE_VRAM					0x11
 
 	FORCE_REFRESH_SCREEN 		0xE0
 	FORCE_CLEAR_SCREEN 			0xE1
+	FORCE_REDRAW_SCREEN 		0xE2
 @end
 @raw_export_end
 @export_comment BIOS_API " --\n"

extra/dss/bios_api.dss

@@ -1,5 +1,5 @@
 ## --
-## -- This file is automatically generated by the DragonAssembler (version 0.4.1618) 
+## -- This file is automatically generated by the DragonAssembler (version 0.4.1617) 
 ## -- Please do not modify this file in any way. 
 ## --
 
@@ -47,6 +47,7 @@
     TEXT_SINGLE_CHAR                        { MemoryAddresses.VGA + 0x0004 }
     TEXT_SIGNLE_INVERT                        { MemoryAddresses.VGA + 0x0005 }
     TEXT_SIGNLE_STR                            { MemoryAddresses.VGA + 0x0006 }
+    FLAGS                                    { MemoryAddresses.VGA + 0x007E }
     MEMORY_CONTROLLER_X                        { MemoryAddresses.VGA + 0x0080 }
     MEMORY_CONTROLLER_X_BYTE                { MemoryAddresses.VGA + 0x0080 + 1 }
     MEMORY_CONTROLLER_Y                        { MemoryAddresses.VGA + 0x0082 }
@@ -83,15 +84,18 @@
     PRINT_STRING        0x07
     REFRESH_SCREEN         0xE0
     CLEAR_SCREEN         0xE1
+    REDRAW_SCREEN         0xE2
 @end
 ## --
 
 ## These are signals used to comunicate with the video card's interface, when in TEXT16_COLOR mode.
 @group Sig_VGA_Text_16_Color
     CONTINUE                     0x00
+    SWAP_BUFFERS                0x10
     WRITE_VRAM                    0x11
     FORCE_REFRESH_SCREEN         0xE0
     FORCE_CLEAR_SCREEN             0xE1
+    FORCE_REDRAW_SCREEN         0xE2
 @end
 ## --
 

extra/dss/drake/bootsector.dss

@@ -39,45 +39,55 @@ _drake_bootsector_entry_point:
 	## Enable Text16 Video Mode
 	movb [VGA_Registers.VIDEO_MODE], VGA_VideoModes.TEXT_16_COLORS
 
-	## Clear screen
-	push DefaultPalette.DarkBlue
-	push 1
-	call $_clear_screen
-
 	## Validate DPT Block
 	mov ACC, [$dpt_block]
 	jne $_invalid_dpt_block, 0xF1CA
 
-	## Print system info
-	push 0
-	call $_print_system_info
-
 	## Init Keyboard driver
 	push $_key_pressed		## KeyPressed handler address passed to the _init_keyboard subroutine
 	push 1
 	call $_init_keyboard
 
+	## Enable Double buffering
+	## mov R2, [VGA_Registers.FLAGS]
+	## or R2, 0b0000000000000001
+	## mov [VGA_Registers.FLAGS], ACC
+
 	## @call(_clear_screen, DefaultPalette.DarkBlue)
 	## @_clear_screen(DefaultPalette.DarkBlue)
 
-
 	## mov R10, 0x22
 	## mov R8, { $dpt_block + DPTStructure.ENTRIES_START + (2 * DPTStructure.ENTRY_SIZE_B) + DPTStructure.ENTRY_PART_LBL }
 	## mov R9, $textCell
 	## int 0x30
 
 	jmp $_endless_loop
-_invalid_dpt_block:
+_invalid_dpt_block: ## TODO: Fix screen drawing on error
 	push $invalid_dpt_block_str
 	push 1
 	call $_print_error_msg
+	jmp $_main_end
 _endless_loop:
 
+	## Clear screen
+	push DefaultPalette.DarkBlue
+	push 1
+	call $_clear_screen
+
+	## Print system info
+	push 0
+	call $_print_system_info
+
 	## Draw main box
 	push 0
 	call $_print_main_box
 
+	## Swap the buffers
+	push 0
+	call $_swap_buffers
+
 	jmp $_endless_loop
+_main_end:
 	hlt
 ## =========================================================================================================================
 
@@ -134,6 +144,24 @@ _clear_screen:  ## _clear_screen(int8_t color)
 
 
 
+## =========================================================================================================================
+_redraw_screen:
+	movb [VGA_Registers.SIGNAL], Sig_VGA_Text_16_Color.FORCE_REDRAW_SCREEN
+	ret
+## =========================================================================================================================
+
+
+
+
+## =========================================================================================================================
+_swap_buffers:
+	movb [VGA_Registers.SIGNAL], Sig_VGA_Text_16_Color.SWAP_BUFFERS
+	ret
+## =========================================================================================================================
+
+
+
+
 ## =========================================================================================================================
 _print_main_box:
 	movb [$textCell.CoordX], 5

extra/info/info

@@ -99,10 +99,14 @@
 
             0xE0: Refresh Screen
             0xE1: Clear Screen
+            0xE2: Redraw Screen
         0x04: Text Single Color Character (1 Byte)
         0x05: Text Single Color Inverted colors (1 Byte)
         0x06: (2 bytes) Text Single Color Buffered String Address
         
+        0x7E: Flags (2 Bytes)
+            0b00000000.00000001: Double Buffering Enabled
+            0b00000000.00000010: Disable Screen Redraw
         0x80: Memory Controller
             0x80: XCoordinate (2 Bytes)
             0x84: YCoordinate (2 Bytes)

extra/info/todo.txt

@@ -1,3 +1,7 @@
+Runtime:
+	Add in place logic operators (and, or...) to ExtAlu CPU Extension
+	Implement native flags operators (set, zero, toggle)
+
 Assembler:
 	Add subroutine address export functionality
 

src/hardware/VirtualDisplay.cpp

@@ -70,11 +70,10 @@ namespace dragon
 				}
 			}
 			
+			m_redrawScreen = m_redrawScreen && !DragonRuntime::vGraphicsInterface.readFlag(hw::interface::Graphics::tFlags::ScreenRedrawDisabled);
 			if (m_redrawScreen)
 			{
-				m_renderer.updateBuffer();
+				__redraw_screen();
-				DragonRuntime::cpu.handleInterrupt(data::InterruptCodes::Text16ModeScreenRefreshed, true);
-				m_redrawScreen = false;
 			}
 			m_renderer.displayBuffer();
 		}
@@ -170,6 +169,15 @@ namespace dragon
 					m_redrawScreen = true;
 					m_refreshScreen = true;
 				}
+				else if (signal == tSignalValues::RedrawScreen)
+				{
+					__redraw_screen();
+				}
+				else if (signal == tSignalValues::Text16Color_SwapBuffers)
+				{
+					DragonRuntime::vGraphicsInterface.swapBuffers_16Colors();
+					__redraw_screen();
+				}
 			}
 			else return;
 			mem.write8(vga_addr + tRegisters::Signal, tSignalValues::Continue);
@@ -197,6 +205,14 @@ namespace dragon
 
 		void VirtualDisplay::onSlowUpdate(void) {  }
 
+		void VirtualDisplay::__redraw_screen(void)
+		{
+			m_renderer.updateBuffer();
+			DragonRuntime::cpu.handleInterrupt(data::InterruptCodes::Text16ModeScreenRefreshed, true);
+			m_redrawScreen = false;
+			m_refreshScreen = true;
+		}
+
 		void VirtualDisplay::single_text_add_char_to_line(char c)
 		{
 			auto& config = DragonRuntime::machine_config;

src/hardware/VirtualDisplay.hpp

@@ -21,6 +21,8 @@ namespace dragon
 				inline static constexpr uint8_t TextSingleInvertColors = 0x05;
 				inline static constexpr uint8_t TextSingleString = 0x06;
 
+				inline static constexpr uint8_t Flags = 0x7E;
+
 				inline static constexpr uint8_t MemControllerX = 0x80;
 				inline static constexpr uint8_t MemControllerY = 0x82;
 				inline static constexpr uint8_t MemControllerChar = 0x84;
@@ -43,10 +45,12 @@ namespace dragon
 				inline static constexpr uint8_t TextSingleColor_DirectPrintBuffNoFlush = 0x06;	
 				inline static constexpr uint8_t TextSingleColor_DirectPrintString = 0x07;
 
+				inline static constexpr uint8_t Text16Color_SwapBuffers = 0x10;
 				inline static constexpr uint8_t Text16Color_WriteMemory = 0x11;
 
 				inline static constexpr uint8_t RefreshScreen = 0xE0;	
 				inline static constexpr uint8_t ClearSCreen = 0xE1;	
+				inline static constexpr uint8_t RedrawScreen = 0xE2;	
 			};
 			public:
 				void onInitialize(void) override;
@@ -59,6 +63,8 @@ namespace dragon
 				inline void redrawScreen(void) { m_redrawScreen = true; }
 
 			private:
+				void __redraw_screen(void);
+
 				void single_text_add_char_to_line(char c);
 				void single_text_add_char_to_buffer(char c);
 				void single_text_flush_buffer(void);

src/hardware/VirtualIODevices.cpp

@@ -662,6 +662,9 @@ namespace dragon
 			{
 				m_videoMemory.init(0xFFFF);
 				m_vramStart = data::MemoryMapAddresses::VideoCardInterface_End - data::MemoryMapAddresses::VideoCardInterface_Start;
+				m_16Color_frameSize = RawTextRenderer::CONSOLE_CHARS_H * RawTextRenderer::CONSOLE_CHARS_V * m_16Color_cellSize;
+				m_16Color_currentFrameAddr = m_vramStart;
+				m_16Color_secondFrameAddr = m_vramStart + m_16Color_frameSize;
 			}
 
 			int8_t Graphics::read8(uint16_t addr)
@@ -706,6 +709,28 @@ namespace dragon
 				return value;
 			}
 
+			bool Graphics::readFlag(uint8_t flg)
+			{
+				if (flg >= 16) return false;
+				int16_t outValue = 0;
+				if (!m_videoMemory.r_Word(VirtualDisplay::tRegisters::Flags, outValue))
+					return false; //TODO: Error
+				m_tempFlags.value = outValue;
+				return ostd::Bits::get(m_tempFlags, flg);
+			}
+
+			void Graphics::setFlag(uint8_t flg, bool val)
+			{
+				if (flg >= 16) return;
+				int16_t outValue = 0;
+				if (!m_videoMemory.r_Word(VirtualDisplay::tRegisters::Flags, outValue))
+					return; //TODO: Error
+				m_tempFlags.value = outValue;
+				ostd::Bits::val(m_tempFlags, flg, val);
+				if (!m_videoMemory.w_Word(VirtualDisplay::tRegisters::Flags, m_tempFlags.value))
+					return; //TODO: Error
+			}
+
 			ostd::ByteStream* Graphics::getByteStream(void)
 			{
 				return &m_videoMemory.getData();
@@ -714,7 +739,7 @@ namespace dragon
 			bool Graphics::readVRAM_16Colors(uint8_t x, uint8_t y, Graphics::tText16_Cell& outTextCell)
 			{
 				uint16_t cellOffset = static_cast<uint16_t>(CONVERT_2D_1D(x, y, RawTextRenderer::CONSOLE_CHARS_H)) * 4;
-				cellOffset += m_vramStart;
+				cellOffset += m_16Color_currentFrameAddr;
 				int8_t outVal = 0;
 				if (!m_videoMemory.r_Byte(cellOffset + tText16_CellStructure::character, outVal))
 					return false; //TODO: Error
@@ -731,7 +756,10 @@ namespace dragon
 			bool Graphics::writeVRAM_16Colors(uint8_t x, uint8_t y, uint8_t character, uint8_t background, uint8_t foreground)
 			{
 				uint16_t cellOffset = static_cast<uint16_t>(CONVERT_2D_1D(x, y, RawTextRenderer::CONSOLE_CHARS_H)) * 4;
-				cellOffset += m_vramStart;
+				if (!readFlag(tFlags::DoubleBufferingEnabled))
+					cellOffset += m_16Color_currentFrameAddr;
+				else
+					cellOffset += m_16Color_secondFrameAddr;
 				if (!m_videoMemory.w_Byte(cellOffset + tText16_CellStructure::character, character))
 					return false; //TODO: Error
 				if (!m_videoMemory.w_Byte(cellOffset + tText16_CellStructure::background, background))
@@ -743,7 +771,7 @@ namespace dragon
 
 			bool Graphics::clearVRAM_16Colors(uint8_t character, uint8_t background, uint8_t foreground)
 			{
-				for (int32_t i = m_vramStart; i < m_vramStart + (RawTextRenderer::CONSOLE_CHARS_H * RawTextRenderer::CONSOLE_CHARS_V) * 4; i += 4)
+				for (int32_t i = m_16Color_currentFrameAddr; i < m_16Color_currentFrameAddr + m_16Color_frameSize; i += 4)
 				{
 					m_videoMemory.w_Byte(i + tText16_CellStructure::character, character);
 					m_videoMemory.w_Byte(i + tText16_CellStructure::background, background);
@@ -752,6 +780,25 @@ namespace dragon
 				return true;
 			}
 
+			void Graphics::swapBuffers_16Colors(void)
+			{
+				if (!readFlag(tFlags::DoubleBufferingEnabled))
+					return;
+				for (int32_t i = m_16Color_currentFrameAddr, j = 0; i < m_16Color_currentFrameAddr + m_16Color_frameSize; i += 4, j += 4)
+				{
+					int8_t outByte = 0;
+					m_videoMemory.r_Byte(m_16Color_secondFrameAddr + j, outByte);
+					m_videoMemory.w_Byte(i + tText16_CellStructure::character, outByte);
+					m_videoMemory.r_Byte(m_16Color_secondFrameAddr + j + 1, outByte);
+					m_videoMemory.w_Byte(i + tText16_CellStructure::background, outByte);
+					m_videoMemory.r_Byte(m_16Color_secondFrameAddr + j + 2, outByte);
+					m_videoMemory.w_Byte(i + tText16_CellStructure::foreground, outByte);
+				}
+				uint16_t tmp = m_16Color_currentFrameAddr;
+				m_16Color_currentFrameAddr = m_16Color_secondFrameAddr;
+				m_16Color_secondFrameAddr = tmp;
+			}
+
 
 
 

src/hardware/VirtualIODevices.hpp

@@ -358,6 +358,11 @@ namespace dragon
 					inline static constexpr uint8_t background	=			0x02;
 					inline static constexpr uint8_t reserved	=			0x03;
 				};
+				public: struct tFlags
+				{
+					inline static constexpr uint8_t DoubleBufferingEnabled 	=		0;
+					inline static constexpr uint8_t ScreenRedrawDisabled 	=		1;
+				};
 				public:
 					Graphics(void);
 					int8_t read8(uint16_t addr) override;
@@ -365,18 +370,28 @@ namespace dragon
 					int8_t write8(uint16_t addr, int8_t value) override;
 					int16_t write16(uint16_t addr, int16_t value) override;
 
+					bool readFlag(uint8_t flg);
+					void setFlag(uint8_t flg, bool val = true);
+
 					ostd::ByteStream* getByteStream(void) override;
 
 					inline uint16_t getVRAMStart(void) { return m_vramStart; }
 					bool readVRAM_16Colors(uint8_t x, uint8_t y, tText16_Cell& outTextCell);
 					bool writeVRAM_16Colors(uint8_t x, uint8_t y, uint8_t character = 0, uint8_t background = 0xFF, uint8_t foreground = 0xFF);
 					bool clearVRAM_16Colors(uint8_t character = 0, uint8_t background = 0x00, uint8_t foreground = 0xFF);
+					void swapBuffers_16Colors(void);
 
 				private:
 					ostd::serial::SerialIO m_videoMemory;
 
 					uint16_t m_vramStart { 0 };
 					uint8_t m_16Color_cellSize { 4 };
+					uint16_t m_16Color_frameSize { 0 };
+					uint16_t m_16Color_secondFrameAddr { 0 };
+					uint16_t m_16Color_currentFrameAddr { 0 };
+					bool m_16Color_doubleBufferingEnabled { false };
+
+					ostd::BitField_16 m_tempFlags;
 			};
 			class SerialPort : public IMemoryDevice
 			{