ADD: Tweaks and improvements on the Operating System.

Signed-off-by: Amlal El Mahrouss <amlal.elmahrouss@icloud.com>

14 files changed, 279 insertions, 70 deletions

diff --git a/ReadMe.md b/ReadMe.md
index 222e5522..7e0cd72f 100644
--- a/ReadMe.md
+++ b/ReadMe.md
@@ -14,9 +14,10 @@ A Microkernel written in C++ 20, with a System Call Interface Library, and custo
 ## Requirements:
 
 - MinGW/GCC
+- LibCompiler
 - Netwide Assembler
 - Git
-- BTB
+- BTB/OpenBTB
 
 ## Installation:
 
diff --git a/debug_ata.sh b/debug_ata.sh
index c32304d3..7699ec05 100755
--- a/debug_ata.sh
+++ b/debug_ata.sh
@@ -1,11 +1,11 @@
 #!/bin/sh
 
 export ATA_PIO_SUPPORT=1
-export ATA_DMA_SUPPORT=
+unset ATA_DMA_SUPPORT
 export DEBUG_SUPPORT=1
 
-cd dev/Kernel
+cd kernel
 make -f amd64-desktop.make all
-cd ../Boot
+cd ../boot
 make -f amd64-desktop.make all
-make -f amd64-desktop.make run-efi-amd64-ata
+make -f amd64-desktop.make run-efi-amd64-ata-pio
diff --git a/dev/Boot/amd64-desktop.make b/dev/Boot/amd64-desktop.make
index e2b73c99..46eb8fc2 100644
--- a/dev/Boot/amd64-desktop.make
+++ b/dev/Boot/amd64-desktop.make
@@ -84,10 +84,17 @@ compile-amd64:
 run-efi-amd64-ahci:
 	$(EMU) $(EMU_FLAGS) -M q35 -hda $(IMG) -s -S
 
-.PHONY: run-efi-amd64-ata
-run-efi-amd64-ata:
+.PHONY: run-efi-amd64-ata-pio
+run-efi-amd64-ata-pio:
+	$(EMU) $(EMU_FLAGS) -M q35 -device piix3-ide,id=ide -drive id=disk,file=$(IMG),format=raw,if=none -device ide-hd,drive=disk,bus=ide.0 -s -S
+
+.PHONY: run-efi-amd64-ata-dma
+run-efi-amd64-ata-dma:
 	$(EMU) $(EMU_FLAGS) -M q35 -device piix4-ide,id=ide -drive id=disk,file=$(IMG),format=raw,if=none -device ide-hd,drive=disk,bus=ide.0 -s -S
 
+.PHONY: run-efi-amd64-ata
+run-efi-amd64-ata: run-efi-amd64-ata-dma
+
 # img_2 is the rescue disk. img is the bootable disk, as provided by the Zeta specs.
 .PHONY: epm-img
 epm-img:
diff --git a/dev/Kernel/HALKit/AMD64/Storage/ATA.cc b/dev/Kernel/HALKit/AMD64/Storage/DMA.cc
index 25143a6d..6fa98a24 100644
--- a/dev/Kernel/HALKit/AMD64/Storage/ATA.cc
+++ b/dev/Kernel/HALKit/AMD64/Storage/DMA.cc
@@ -18,7 +18,7 @@
 #include <Mod/ATA/ATA.h>
 #include <ArchKit/ArchKit.h>
 
-#if defined(__ATA_PIO__) || defined(__ATA_DMA__)
+#if defined(__ATA_DMA__)
 
 #define kATADataLen 256
 
@@ -37,18 +37,18 @@ Boolean drv_std_wait_io(UInt16 IO)
 		rt_in8(IO + ATA_REG_STATUS);
 
 ATAWaitForIO_Retry:
-	auto rdy = rt_in8(IO + ATA_REG_STATUS);
+	auto statRdy = rt_in8(IO + ATA_REG_STATUS);
 
-	if ((rdy & ATA_SR_BSY))
+	if ((statRdy & ATA_SR_BSY))
 		goto ATAWaitForIO_Retry;
 
 ATAWaitForIO_Retry2:
-	rdy = rt_in8(IO + ATA_REG_STATUS);
+	statRdy = rt_in8(IO + ATA_REG_STATUS);
 
-	if (rdy & ATA_SR_ERR)
+	if (statRdy & ATA_SR_ERR)
 		return false;
 
-	if (!(rdy & ATA_SR_DRDY))
+	if (!(statRdy & ATA_SR_DRDY))
 		goto ATAWaitForIO_Retry2;
 
 	return true;
@@ -64,45 +64,44 @@ Void drv_std_select(UInt16 Bus)
 
 Boolean drv_std_init(UInt16 Bus, UInt8 Drive, UInt16& OutBus, UInt8& OutMaster)
 {
+	if (drv_std_detected())
+		return true;
+
 	UInt16 IO = Bus;
+
 	drv_std_select(IO);
 
+	// Bus init, NEIN bit.
 	rt_out8(IO + ATA_REG_NEIN, 1);
 
-	// Step 1: Wait until drive is not busy
-	int timeout = 100000;
-	while ((rt_in8(IO + ATA_REG_STATUS) & ATA_SR_BSY) && --timeout)
-		;
-	if (!timeout)
+	// identify until it's good.
+ATAInit_Retry:
+	auto statRdy = rt_in8(IO + ATA_REG_STATUS);
+
+	if (statRdy & ATA_SR_ERR)
 	{
-		kout << "Timeout waiting for drive to become ready...\r";
 		return false;
 	}
 
-	// Step 2: Send IDENTIFY command
+	if ((statRdy & ATA_SR_BSY))
+		goto ATAInit_Retry;
+
 	rt_out8(IO + ATA_REG_COMMAND, ATA_CMD_IDENTIFY);
 
-	// Step 3: Wait for the drive to be ready (not busy)
-	drv_std_wait_io(IO);
+	/// fetch serial info
+	/// model, speed, number of sectors...
 
-	// Step 4: Check for errors
-	UInt8 status = rt_in8(IO + ATA_REG_STATUS);
-	if (status & ATA_SR_ERR)
-	{
-		kout << "ATA Error, aborting...\r";
-		return false;
-	}
+	drv_std_wait_io(IO);
 
-	// Step 5: Read IDENTIFY DEVICE response
-	for (SizeT indexData = 0UL; indexData < kATADataLen; ++indexData)
+	for (SizeT indexData = 0ul; indexData < kATADataLen; ++indexData)
 	{
-		kATAData[indexData] = rt_in16(IO + ATA_REG_DATA);
+		kATAData[indexData] = Kernel::HAL::rt_in16(IO + ATA_REG_DATA);
 	}
 
-	// Step 6: Set OutBus & OutMaster correctly
 	OutBus	  = (Bus == ATA_PRIMARY_IO) ? ATA_PRIMARY_IO : ATA_SECONDARY_IO;
-	OutMaster = (Drive == ATA_MASTER) ? ATA_MASTER : ATA_SLAVE;
+	OutMaster = (Bus == ATA_PRIMARY_IO) ? ATA_MASTER : ATA_SLAVE;
 
+	return true;
 #ifdef __ATA_DMA__
 	// Step 7: Check if the drive supports DMA
 	if (!(kATAData[63] & (1 << 8)) || !(kATAData[88] & 0xFF))
@@ -162,20 +161,10 @@ Void drv_std_read(UInt64 Lba, UInt16 IO, UInt8 Master, Char* Buf, SizeT SectorSz
 	rt_out8(IO + ATA_REG_LBA2, (Lba) >> 16);
 	rt_out8(IO + ATA_REG_LBA3, (Lba) >> 24);
 
-#ifdef __ATA_PIO__
-	rt_out8(ATA_REG_COMMAND, ATA_CMD_READ_PIO);
-
-	for (SizeT IndexOff = 0; IndexOff < Size; ++IndexOff)
-	{
-		drv_std_wait_io(IO);
-		rt_out16(IO + ATA_REG_DATA, Buf[IndexOff]);
-		drv_std_wait_io(IO);
-	}
-#else
 	if (Size > kib_cast(64))
 		ke_panic(RUNTIME_CHECK_FAILED, "ATA-DMA only supports < 64kb DMA transfers.");
 
-	Details::PRD* prd = (Details::PRD*)mib_cast(4);
+	Details::PRD* prd = new Details::PRD();
 	prd->mAddress	  = (UInt32)(UIntPtr)Buf;
 	prd->mByteCount	  = Size;
 	prd->mFlags		  = 0x8000;
@@ -187,8 +176,10 @@ Void drv_std_read(UInt64 Lba, UInt16 IO, UInt8 Master, Char* Buf, SizeT SectorSz
 
 	while (rt_in8(ATA_REG_STATUS) & 0x01)
 		;
-	rt_out8(IO + 0x00, 0x00); // Start DMA engine
-#endif // __ATA_PIO__
+	rt_out8(IO + 0x00, 0x00); // Stop DMA engine
+
+	delete prd;
+	prd = nullptr;
 }
 
 Void drv_std_write(UInt64 Lba, UInt16 IO, UInt8 Master, Char* Buf, SizeT SectorSz, SizeT Size)
@@ -208,20 +199,10 @@ Void drv_std_write(UInt64 Lba, UInt16 IO, UInt8 Master, Char* Buf, SizeT SectorS
 	rt_out8(IO + ATA_REG_LBA2, (Lba) >> 16);
 	rt_out8(IO + ATA_REG_LBA3, (Lba) >> 24);
 
-#ifdef __ATA_PIO__
-	rt_out8(ATA_REG_COMMAND, ATA_CMD_WRITE_PIO);
-
-	for (SizeT IndexOff = 0; IndexOff < Size; ++IndexOff)
-	{
-		drv_std_wait_io(IO);
-		rt_out16(IO + ATA_REG_DATA, Buf[IndexOff]);
-		drv_std_wait_io(IO);
-	}
-#else
 	if (Size > kib_cast(64))
 		ke_panic(RUNTIME_CHECK_FAILED, "ATA-DMA only supports < 64kb DMA transfers.");
 
-	Details::PRD* prd = (Details::PRD*)mib_cast(4);
+	Details::PRD* prd = new Details::PRD();
 	prd->mAddress	  = (UInt32)(UIntPtr)Buf;
 	prd->mByteCount	  = Size;
 	prd->mFlags		  = 0x8000;
@@ -234,8 +215,10 @@ Void drv_std_write(UInt64 Lba, UInt16 IO, UInt8 Master, Char* Buf, SizeT SectorS
 	while (rt_in8(ATA_REG_STATUS) & 0x01)
 		;
 
-	rt_out8(IO + 0x00, 0x00); // Start DMA engine
-#endif // __ATA_PIO__
+	rt_out8(IO + 0x00, 0x00); // Stop DMA engine
+
+	delete prd;
+	prd = nullptr;
 }
 
 /// @brief is ATA detected?
@@ -258,4 +241,4 @@ Kernel::SizeT drv_get_size()
 	return (drv_get_sector_count()) * kATASectorSize;
 }
 
-#endif /* ifdef __ATA_PIO__ */
+#endif /* ifdef __ATA_DMA__ */
diff --git a/dev/Kernel/HALKit/AMD64/Storage/PIO.cc b/dev/Kernel/HALKit/AMD64/Storage/PIO.cc
new file mode 100644
index 00000000..3f1286b6
--- /dev/null
+++ b/dev/Kernel/HALKit/AMD64/Storage/PIO.cc
@@ -0,0 +1,189 @@
+/* -------------------------------------------
+
+	Copyright (C) 2024-2025, Amlal EL Mahrouss, all rights reserved.
+
+------------------------------------------- */
+
+/**
+ * @file ATA-PIO.cc
+ * @author Amlal EL Mahrouss (amlalelmahrouss@icloud.com)
+ * @brief ATA driver (PIO mode).
+ * @version 0.1
+ * @date 2024-02-02
+ *
+ * @copyright Copyright (c) Amlal EL Mahrouss
+ *
+ */
+
+#include <Mod/ATA/ATA.h>
+#include <ArchKit/ArchKit.h>
+
+#ifdef __ATA_PIO__
+
+using namespace Kernel;
+using namespace Kernel::HAL;
+
+/// bugs: 0
+
+#define kATADataLen 256
+
+STATIC Boolean kATADetected			 = false;
+STATIC Int32   kATADeviceType		 = kATADeviceCount;
+STATIC Char	   kATAData[kATADataLen] = {0};
+
+Boolean drv_std_wait_io(UInt16 IO)
+{
+	for (int i = 0; i < 400; i++)
+		rt_in8(IO + ATA_REG_STATUS);
+
+ATAWaitForIO_Retry:
+	auto statRdy = rt_in8(IO + ATA_REG_STATUS);
+
+	if ((statRdy & ATA_SR_BSY))
+		goto ATAWaitForIO_Retry;
+
+ATAWaitForIO_Retry2:
+	statRdy = rt_in8(IO + ATA_REG_STATUS);
+
+	if (statRdy & ATA_SR_ERR)
+		return false;
+
+	if (!(statRdy & ATA_SR_DRDY))
+		goto ATAWaitForIO_Retry2;
+
+	return true;
+}
+
+Void drv_std_select(UInt16 Bus)
+{
+	if (Bus == ATA_PRIMARY_IO)
+		rt_out8(Bus + ATA_REG_HDDEVSEL, ATA_PRIMARY_SEL);
+	else
+		rt_out8(Bus + ATA_REG_HDDEVSEL, ATA_SECONDARY_SEL);
+}
+
+Boolean drv_std_init(UInt16 Bus, UInt8 Drive, UInt16& OutBus, UInt8& OutMaster)
+{
+	if (drv_std_detected())
+		return true;
+
+	UInt16 IO = Bus;
+
+	drv_std_select(IO);
+
+	// Bus init, NEIN bit.
+	rt_out8(IO + ATA_REG_NEIN, 1);
+
+	// identify until it's good.
+ATAInit_Retry:
+	auto statRdy = rt_in8(IO + ATA_REG_STATUS);
+
+	if (statRdy & ATA_SR_ERR)
+	{
+		return false;
+	}
+
+	if ((statRdy & ATA_SR_BSY))
+		goto ATAInit_Retry;
+
+	rt_out8(IO + ATA_REG_COMMAND, ATA_CMD_IDENTIFY);
+
+	/// fetch serial info
+	/// model, speed, number of sectors...
+
+	drv_std_wait_io(IO);
+
+	for (SizeT indexData = 0ul; indexData < kATADataLen; ++indexData)
+	{
+		kATAData[indexData] = Kernel::HAL::rt_in16(IO + ATA_REG_DATA);
+	}
+
+	OutBus	  = (Bus == ATA_PRIMARY_IO) ? ATA_PRIMARY_IO : ATA_SECONDARY_IO;
+	OutMaster = (Bus == ATA_PRIMARY_IO) ? ATA_MASTER : ATA_SLAVE;
+
+	return true;
+}
+
+Void drv_std_read(UInt64 Lba, UInt16 IO, UInt8 Master, Char* Buf, SizeT SectorSz, SizeT Size)
+{
+	Lba /= SectorSz;
+
+	UInt8 Command = ((!Master) ? 0xE0 : 0xF0);
+
+	drv_std_wait_io(IO);
+	drv_std_select(IO);
+
+	rt_out8(IO + ATA_REG_HDDEVSEL, (Command) | (((Lba) >> 24) & 0x0F));
+
+	rt_out8(IO + ATA_REG_SEC_COUNT0, ((Size + SectorSz) / SectorSz));
+
+	rt_out8(IO + ATA_REG_LBA0, (Lba)&0xFF);
+	rt_out8(IO + ATA_REG_LBA1, (Lba) >> 8);
+	rt_out8(IO + ATA_REG_LBA2, (Lba) >> 16);
+	rt_out8(IO + ATA_REG_LBA3, (Lba) >> 24);
+
+	rt_out8(IO + ATA_REG_COMMAND, ATA_CMD_READ_PIO);
+
+	drv_std_wait_io(IO);
+
+	for (SizeT IndexOff = 0; IndexOff < Size; ++IndexOff)
+	{
+		drv_std_wait_io(IO);
+		Buf[IndexOff] = Kernel::HAL::rt_in16(IO + ATA_REG_DATA);
+		drv_std_wait_io(IO);
+	}
+}
+
+Void drv_std_write(UInt64 Lba, UInt16 IO, UInt8 Master, Char* Buf, SizeT SectorSz, SizeT Size)
+{
+	Lba /= SectorSz;
+
+	UInt8 Command = ((!Master) ? 0xE0 : 0xF0);
+
+	drv_std_wait_io(IO);
+	drv_std_select(IO);
+
+	rt_out8(IO + ATA_REG_HDDEVSEL, (Command) | (((Lba) >> 24) & 0x0F));
+
+	rt_out8(IO + ATA_REG_SEC_COUNT0, ((Size + (SectorSz)) / SectorSz));
+
+	rt_out8(IO + ATA_REG_LBA0, (Lba)&0xFF);
+	rt_out8(IO + ATA_REG_LBA1, (Lba) >> 8);
+	rt_out8(IO + ATA_REG_LBA2, (Lba) >> 16);
+	rt_out8(IO + ATA_REG_LBA3, (Lba) >> 24);
+
+	rt_out8(IO + ATA_REG_COMMAND, ATA_CMD_WRITE_PIO);
+
+	drv_std_wait_io(IO);
+
+	for (SizeT IndexOff = 0; IndexOff < Size; ++IndexOff)
+	{
+		drv_std_wait_io(IO);
+		rt_out16(IO + ATA_REG_DATA, Buf[IndexOff]);
+		drv_std_wait_io(IO);
+	}
+
+	drv_std_wait_io(IO);
+}
+
+/// @brief is ATA detected?
+Boolean drv_std_detected(Void)
+{
+	return kATADetected;
+}
+
+/***
+     @brief Getter, gets the number of sectors inside the drive.
+ */
+Kernel::SizeT drv_get_sector_count()
+{
+	return (kATAData[61] << 16) | kATAData[60];
+}
+
+/// @brief Get the drive size.
+Kernel::SizeT drv_get_size()
+{
+	return (drv_get_sector_count()) * kATASectorSize;
+}
+
+#endif /* ifdef __ATA_PIO__ */
diff --git a/dev/Kernel/HALKit/AMD64/Storage/SATA.cc b/dev/Kernel/HALKit/AMD64/Storage/SATA.cc
index 26391340..00ef8767 100644
--- a/dev/Kernel/HALKit/AMD64/Storage/SATA.cc
+++ b/dev/Kernel/HALKit/AMD64/Storage/SATA.cc
@@ -184,8 +184,13 @@ static Kernel::Void drv_std_input_output(Kernel::UInt64 lba, Kernel::UInt8* buff
 	if (slot == -1)
 		return;
 
+	if (size_buffer > mib_cast(4))
+		Kernel::ke_panic(RUNTIME_CHECK_FAILED, "AHCI only supports < 4mb DMA transfers.");
+
 	HbaCmdHeader* command_header = ((HbaCmdHeader*)((Kernel::UInt64)kSATAPort->Ports[kSATAPortIdx].Clb + kSATAPort->Ports[kSATAPortIdx].Clbu));
 
+	command_header += slot;
+
 	Kernel::rt_set_memory(reinterpret_cast<Kernel::VoidPtr>(command_header), 0, sizeof(HbaCmdHeader));
 
 	MUST_PASS(command_header);
@@ -200,10 +205,10 @@ static Kernel::Void drv_std_input_output(Kernel::UInt64 lba, Kernel::UInt8* buff
 
 	MUST_PASS(command_table);
 
-	command_table->Prdt[0].Dba			= ((Kernel::UInt32)(Kernel::UInt64)Kernel::HAL::hal_get_phys_address(buffer));
-	command_table->Prdt[0].Dbau			= (((Kernel::UInt64)Kernel::HAL::hal_get_phys_address(buffer) >> 32));
-	command_table->Prdt[0].Dbc			= ((size_buffer)-1);
-	command_table->Prdt[0].InterruptBit = 1;
+	command_table->Prdt[0].Dba	= ((Kernel::UInt32)(Kernel::UInt64)Kernel::HAL::hal_get_phys_address(buffer));
+	command_table->Prdt[0].Dbau = (((Kernel::UInt64)Kernel::HAL::hal_get_phys_address(buffer) >> 32));
+	command_table->Prdt[0].Dbc	= ((size_buffer)-1);
+	command_table->Prdt[0].IE	= 1;
 
 	command_header->Ctba  = ((Kernel::UInt32)(Kernel::UInt64)command_table);
 	command_header->Ctbau = ((Kernel::UInt32)((Kernel::UInt64)command_table >> 32));
diff --git a/dev/Kernel/src/DriveMgr.cc b/dev/Kernel/src/DriveMgr.cc
index 7230f112..f7215346 100644
--- a/dev/Kernel/src/DriveMgr.cc
+++ b/dev/Kernel/src/DriveMgr.cc
@@ -162,6 +162,8 @@ namespace Kernel
 
 			trait.fInit(trait.fPacket);
 
+			kout << "Reading EPM block...\r";
+
 			trait.fInput(trait.fPacket);
 
 			if (rt_string_cmp(((BOOT_BLOCK_STRUCT*)trait.fPacket.fPacketContent)->Magic, kEPMMagic, kEPMMagicLength) == 0)
diff --git a/dev/Mod/AHCI/AHCI.h b/dev/Mod/AHCI/AHCI.h
index 43fe4f0b..05f75391 100644
--- a/dev/Mod/AHCI/AHCI.h
+++ b/dev/Mod/AHCI/AHCI.h
@@ -91,7 +91,7 @@ typedef struct FisRegD2H final
 
 	Kernel::UInt8 PortMul : 4;		// Port multiplier
 	Kernel::UInt8 Reserved0 : 2;	// Reserved
-	Kernel::UInt8 InterruptBit : 1; // Interrupt bit
+	Kernel::UInt8 IE : 1; // Interrupt bit
 	Kernel::UInt8 Reserved1 : 1;	// Reserved
 
 	Kernel::UInt8 Status; // Status register
@@ -140,7 +140,7 @@ typedef struct FisPioSetup final
 	Kernel::UInt8 PortMul : 4;		// Port multiplier
 	Kernel::UInt8 Reserved0 : 1;	// Reserved
 	Kernel::UInt8 DTD : 1;			// Data transfer direction, 1 - device to host
-	Kernel::UInt8 InterruptBit : 1; // Interrupt bit
+	Kernel::UInt8 IE : 1; // Interrupt bit
 	Kernel::UInt8 Reserved1 : 1;
 
 	Kernel::UInt8 Status; // Status register
@@ -177,7 +177,7 @@ typedef struct FisDmaSetup final
 	Kernel::UInt8 PortMul : 4;		// Port multiplier
 	Kernel::UInt8 Reserved0 : 1;	// Reserved
 	Kernel::UInt8 DTD : 1;			// Data transfer direction, 1 - device to host
-	Kernel::UInt8 InterruptBit : 1; // Interrupt bit
+	Kernel::UInt8 IE : 1; // Interrupt bit
 	Kernel::UInt8 AutoEnable : 1;	// Auto-activate. Specifies if DMA Activate FIS is needed
 
 	Kernel::UInt8 Reserved1[2]; // Reserved
@@ -207,7 +207,7 @@ typedef struct FisDevBits final
 
 	Kernel::UInt8 Reserved0 : 5; // Reserved
 	Kernel::UInt8 R0 : 1;
-	Kernel::UInt8 InterruptBit : 1;
+	Kernel::UInt8 IE : 1;
 	Kernel::UInt8 N : 1;
 
 	Kernel::UInt8 StatusLow : 3;
@@ -320,7 +320,7 @@ typedef struct HbaPrdtEntry final
 	// DW3
 	Kernel::UInt32 Dbc : 22;		 // Byte count, 4M max
 	Kernel::UInt32 Reserved1 : 9;	 // Reserved
-	Kernel::UInt32 InterruptBit : 1; // Interrupt on completion
+	Kernel::UInt32 IE : 1; // Interrupt on completion
 } HbaPrdtEntry;
 
 typedef struct HbaCmdTbl final
diff --git a/doc/AHCI.drawio b/doc/AHCI.drawio
new file mode 100644
index 00000000..191f04aa
--- /dev/null
+++ b/doc/AHCI.drawio
@@ -0,0 +1,22 @@
+<mxfile host="65bd71144e">
+    <diagram id="n4yoMa775TB45TuBg3XL" name="Page-1">
+        <mxGraphModel dx="1144" dy="698" grid="1" gridSize="10" guides="1" tooltips="1" connect="1" arrows="1" fold="1" page="1" pageScale="1" pageWidth="850" pageHeight="1100" math="0" shadow="0">
+            <root>
+                <mxCell id="0"/>
+                <mxCell id="1" parent="0"/>
+                <mxCell id="4" style="edgeStyle=none;html=1;" edge="1" parent="1" source="2" target="3">
+                    <mxGeometry relative="1" as="geometry"/>
+                </mxCell>
+                <mxCell id="2" value="DEV" style="rounded=1;whiteSpace=wrap;html=1;" vertex="1" parent="1">
+                    <mxGeometry x="490" y="310" width="120" height="170" as="geometry"/>
+                </mxCell>
+                <mxCell id="5" style="edgeStyle=none;html=1;exitX=1;exitY=0.25;exitDx=0;exitDy=0;entryX=0;entryY=0.25;entryDx=0;entryDy=0;" edge="1" parent="1" source="3" target="2">
+                    <mxGeometry relative="1" as="geometry"/>
+                </mxCell>
+                <mxCell id="3" value="HOST" style="rounded=1;whiteSpace=wrap;html=1;" vertex="1" parent="1">
+                    <mxGeometry x="170" y="310" width="120" height="170" as="geometry"/>
+                </mxCell>
+            </root>
+        </mxGraphModel>
+    </diagram>
+</mxfile>
\ No newline at end of file
diff --git a/doc/GUI-System.drawio b/doc/GUI_DESIGN.drawio
index bd31ac14..bd31ac14 100644
--- a/doc/GUI-System.drawio
+++ b/doc/GUI_DESIGN.drawio
diff --git a/doc/OS-Design.drawio b/doc/OS_DESIGN.drawio
index 118a9add..118a9add 100644
--- a/doc/OS-Design.drawio
+++ b/doc/OS_DESIGN.drawio
diff --git a/doc/OS-Scheduler-Design.drawio b/doc/ROUND_ROBIN.drawio
index 46c6304b..46c6304b 100644
--- a/doc/OS-Scheduler-Design.drawio
+++ b/doc/ROUND_ROBIN.drawio
diff --git a/doc/SCHED-DESIGN.drawio b/doc/SCHED_DESIGN.drawio
index ab75d000..ab75d000 100644
--- a/doc/SCHED-DESIGN.drawio
+++ b/doc/SCHED_DESIGN.drawio
diff --git a/doc/OS-Timer-Design.drawio b/doc/TIMER_DESIGN.drawio
index ca081fd3..ca081fd3 100644
--- a/doc/OS-Timer-Design.drawio
+++ b/doc/TIMER_DESIGN.drawio