Kernel Update 1

Makefile

@@ -0,0 +1,42 @@
+CC = gcc
+LD = ld
+OBJCOPY = objcopy
+NASM = nasm
+
+CFLAGS = -m32 -ffreestanding -O2 -Wall -Wextra -I. -std=gnu99 -MMD
+# Use -f win32 for MinGW, -f elf32 for Linux/Cross-Compiler
+NASMFLAGS = -f win32
+LDFLAGS = -T linker.ld
+
+# Auto-detect all .c files in the current folder
+C_SOURCES = $(wildcard *.c)
+# Exclude spinlock.c if it exists (replaced by sync.h implementation)
+C_SOURCES := $(filter-out spinlock.c, $(C_SOURCES))
+# Create a list of .o files to build
+OBJ = $(C_SOURCES:.c=.o)
+
+# Default target
+all: os.img
+
+os.img: boot.bin kernel.bin
+	cat boot.bin kernel.bin > os.img
+
+boot.bin: boot.asm
+	$(NASM) -f bin boot.asm -o boot.bin
+
+kernel.bin: kernel.tmp
+	$(OBJCOPY) -O binary kernel.tmp kernel.bin
+
+kernel.tmp: $(OBJ) interrupt.o
+	$(LD) $(LDFLAGS) -o kernel.tmp $(OBJ) interrupt.o
+
+interrupt.o: interrupt.asm
+	$(NASM) $(NASMFLAGS) interrupt.asm -o interrupt.o
+
+%.o: %.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+-include $(OBJ:.o=.d)
+
+clean:
+	rm -f *.o *.d *.bin *.tmp os.img

NIC.C

@@ -37,7 +37,7 @@ void rtl8139_handler(registers_t *r) {
 void rtl8139_init(void) {
     vga_print_string("Initializing RTL8139... ");
 
-    // --- Find the card (same as before) ---
+    // --- Find the card ---
     uint8_t found = 0;
     for (uint16_t bus = 0; bus < 256; bus++) {
         for (uint8_t device = 0; device < 32; device++) {
@@ -65,9 +65,8 @@ void rtl8139_init(void) {
     // 2. Software Reset
     outb(rtl8139_io_base + REG_COMMAND, 0x10);
     while((inb(rtl8139_io_base + REG_COMMAND) & 0x10) != 0) { /* wait */ }
-
-    // 3. Allocate Receive Buffer (8K + 16 bytes)
-    rx_buffer = (uint8_t*)pmm_alloc(8192 + 16);
+    // 3. Allocate an 16KB block, ie 4 blocks (order 1) for the receive buffer.
+    rx_buffer = (uint8_t*)pmm_alloc_blocks(4);
     outl(rtl8139_io_base + REG_RX_BUF, (uint32_t)rx_buffer);
 
     // 4. Set Interrupt Mask (Enable Receive OK interrupt)

README.md

@@ -1,2 +1,192 @@
-Operating System still under development
-This is a lightweight, Machine Learning based (under the hood for memory management, process allocation etc ) based operating system
+# SimpleOS - A Lightweight x86 Operating System
+
+SimpleOS is a lightweight, robust operating system for the x86 architecture, written in C and Assembly. It provides a foundational set of OS features, including protected mode, memory segmentation, and a full interrupt handling system, making it ideal for embedded applications, legacy system revival, or as a base for custom OS development.
+
+## Features
+
+- **Bootloader**: Custom 16-bit bootloader that transitions to protected mode
+- **GDT (Global Descriptor Table)**: Memory segmentation with kernel/user segments
+- **IDT (Interrupt Descriptor Table)**: Complete interrupt handling system with exception messages
+- **VGA Text Driver**: Full-featured text output with scrolling, colors, and formatting
+- **Keyboard Driver**: PS/2 keyboard support with scan code translation
+- **Interactive Shell**: Command-line interface with built-in commands
+- **Memory Management**: Basic protected mode memory setup
+- **Interrupt Handling**: Proper CPU exception and hardware interrupt handling
+
+## Architecture
+
+### Boot Process
+1. **Real Mode Boot**: 16-bit bootloader loads from sector 0
+2. **A20 Line**: Enable extended memory access
+3. **Protected Mode**: Switch to 32-bit protected mode
+4. **Kernel Entry**: Jump to kernel main function
+
+### Kernel Components
+
+#### VGA Driver (`vga.c`, `vga.h`)
+- Text mode output at 0xB8000
+- 80x25 character display
+- 16-color palette support
+- Automatic scrolling
+- Hex/decimal number formatting
+
+#### GDT Manager (`gdt.c`, `gdt.h`)  
+- 5-entry descriptor table (null, kernel code/data, user code/data)
+- Proper segment reloading
+- 4GB flat memory model
+
+#### IDT Manager (`idt.c`, `idt.h`)
+- 256 interrupt descriptors
+- Exception handlers with descriptive messages
+- Hardware interrupt support (PIC reprogramming)
+- Assembly interrupt stubs (`interrupt.asm`)
+
+#### Keyboard Driver (`keyboard.c`, `keyboard.h`)
+- PS/2 keyboard interrupt handler (IRQ1)
+- Scan code to ASCII translation
+- Shift and Caps Lock support
+- Key buffer for input queuing
+- Integration with shell interface
+
+#### Interactive Shell (`shell.c`, `shell.h`)
+- Command-line interface
+- Built-in commands: help, clear, about, reboot, halt
+- Command history and input processing
+- Backspace support and line editing
+
+#### Kernel Main (`kernel.c`)
+- System initialization sequence  
+- Colorized boot messages
+- Shell initialization and main loop
+
+## Building
+
+### Prerequisites
+
+You need a cross-compilation toolchain for i686-elf:
+- `i686-elf-gcc` (C compiler)
+- `i686-elf-ld` (Linker) 
+- `nasm` (Netwide Assembler)
+
+### Installation on Ubuntu/Debian:
+```bash
+sudo apt-get install build-essential nasm qemu-system-x86
+# For the cross-compiler, you can build it from source.
+# A good guide can be found here: https://wiki.osdev.org/GCC_Cross-Compiler
+# Alternatively, some package managers might have pre-built toolchains.
+```
+
+### Installation on Windows:
+1. Install MSYS2
+2. Install cross-compilation tools:
+```bash
+pacman -S mingw-w64-i686-gcc nasm
+```
+
+### Compilation
+```bash
+make all        # Build OS image
+make clean      # Remove build files
+make qemu       # Run with QEMU (if installed)
+make bochs      # Run with Bochs (if installed)
+make help       # Show available targets
+```
+
+## Running
+
+### QEMU (Recommended)
+```bash
+qemu-system-i386 -fda build/os.img
+```
+
+### Bochs
+```bash
+bochs -f bochsrc.txt
+```
+
+### VirtualBox/VMware
+1. Create new VM with floppy disk
+2. Mount `build/os.img` as floppy image
+3. Boot from floppy
+
+## Using the Shell
+
+Once the system boots, you'll see the SimpleOS shell prompt:
+
+```
+SimpleOS> 
+```
+
+The agent will process your request and respond accordingly.
+
+### Example Interactions
+- `> what time is it?`
+- `> create a new file named notes.txt`
+- `> tell me about the CPU`
+- `> reboot the machine in 5 minutes`
+
+## File Structure
+
+```
+SimpleOS/
+├── boot/
+│   └── boot.asm          # 16-bit bootloader
+├── kernel/
+│   ├── kernel.c          # Kernel main and initialization
+│   ├── gdt.c/.h          # Global Descriptor Table
+│   ├── idt.c/.h          # Interrupt Descriptor Table  
+│   ├── vga.c/.h          # VGA text driver
+│   ├── keyboard.c/.h     # PS/2 keyboard driver
+│   ├── agent.c/.h        # The core AI agent logic
+│   └── interrupt.asm     # Assembly interrupt handlers
+├── build/                # Build output (auto-generated)
+├── Makefile             # Build configuration
+├── linker.ld            # Linker script
+└── README.md            # This file
+```
+
+## Technical Details
+
+### Memory Layout
+- **0x00007C00**: Bootloader load address
+- **0x00100000**: Kernel load address (1MB)
+- **0x000B8000**: VGA text buffer
+- **0x00090000**: Stack pointer
+
+### Interrupts
+- **ISR 0-31**: CPU exceptions (division error, page fault, etc.)
+- **IRQ 0-15**: Hardware interrupts (timer, keyboard, etc.)
+- **PIC Remapping**: Master PIC (0x20-0x27), Slave PIC (0x28-0x2F)
+
+### Color Codes (VGA)
+- 0=Black, 1=Blue, 2=Green, 3=Cyan, 4=Red, 5=Magenta
+- 6=Brown, 7=Light Grey, 8=Dark Grey, 9=Light Blue
+- 10=Light Green, 11=Light Cyan, 12=Light Red
+- 13=Light Magenta, 14=Light Brown, 15=White
+
+## Roadmap
+
+Future development is focused on expanding the kernel's capabilities. Key areas on our roadmap include:
+
+- **Agent Tooling**: Expanding the set of kernel functions (tools) the LLM agent can use.
+- **Long-Term Memory**: Implementing a file system to give the agent persistent memory.
+- **Multitasking**: Allowing the agent to manage and execute multiple background processes.
+
+### Debugging
+- Connect GDB: `gdb -ex "target remote :1234"`
+- Enable QEMU monitor: Add `-monitor stdio`
+
+## Contributing
+
+SimpleOS is an open-source product and we welcome contributions from the community. If you are interested in contributing, please feel free to fork the repository, make your changes, and submit a pull request. We are actively looking for improvements in drivers, memory management, and performance optimizations.
+
+## License
+
+This product is released under the MIT License. See the LICENSE file for details.
+
+## References
+
+- [OSDev Wiki](https://wiki.osdev.org/) - Comprehensive OS development resource
+- [Intel 80386 Manual](https://www.intel.com/content/www/us/en/architecture-and-technology/64-ia-32-architectures-software-developer-vol-3a-part-1-manual.html)
+- [Bran's Kernel Development Tutorial](http://www.osdever.net/bkerndev/Docs/title.htm)
+- [JamesM's Kernel Development Tutorials](https://web.archive.org/web/20160412174753/http://www.jamesmolloy.co.uk/tutorial_html/index.html)