ATmega128 Firmware

Rust-based firmware for the MikroElektronika BigAVR2 development board featuring the ATmega128 microcontroller.

🔧 Hardware Requirements

• MikroElektronika BigAVR2 board
• ATmega128 running at 16MHz
• USB-UART adapter for programming
• Debian 12 (or compatible) development system

📦 Dependencies

• Rust nightly toolchain
• AVR-GCC toolchain
• AVRDUDE for flashing

🚀 Quick Start

1. Install system dependencies:

sudo apt update
sudo apt install avr-gcc gcc-avr avr-libc avrdude

2. Setup Rust:

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
rustup default nightly
rustup target add avr-atmega128

3. Build the project:

cargo build --release --target avr-atmega128.json

4. Flash to board (assuming USB-UART on /dev/ttyUSB0):

avrdude -p m128 -c arduino -P /dev/ttyUSB0 -b 115200 -U flash:w:target/avr-atmega128/release/atmega128_firmware.elf

🏗️ Project Structure

/src
  /drivers         → Board-specific drivers
  /hal             → Hardware abstraction layer
  /application     → Application logic
  /rtos            → Real-time task scheduler
  /config          → Build configuration
/tests             → Hardware-in-loop tests
/hw               → Hardware documentation
/scripts          → Build and flash utilities

🛡️ Safety Considerations

This project uses unsafe Rust in the following contexts:

• Direct hardware register access in HAL layer
• Interrupt handlers
• Critical sections for atomic operations

All unsafe blocks are carefully documented and encapsulated behind safe abstractions.

🔋 Power Management

The firmware implements several power-saving features:

• Sleep modes (Idle, Power-Down)
• Peripheral power control
• Clock gating

📝 Development Notes

• Uses zero-cost abstractions for HAL implementation
• Implements cycle-accurate timing using direct register access
• Defensive programming with Result types for error handling
• Static memory allocation only (#![no_std])

🐛 Debugging

1. Connect JTAG debugger
2. Use OpenOCD for debugging session:

openocd -f interface/jtagkey.cfg -f target/atmega128.cfg

📜 License

MIT License - See LICENSE file for details

⚠️ Known Issues

• ISR latency needs optimization in timer-based operations
• Power consumption in sleep mode higher than expected
• UART baud rate drift at high speeds

🤝 Contributing

1. Fork the repository
2. Create feature branch
3. Commit changes
4. Open pull request

Please follow Rust style guidelines and document unsafe blocks.