inital dump

README.md

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 # lezyne-rear-light-firmware
 
-Open firmware for Lezyne bike rear lights based on ATTINY202
+Open firmware for Lezyne bike rear lights based on ATTINY202
+
+This repository contains a minimal firmware as a **C project** for the ATtiny202 microcontroller using **GCC**, **CMake**, and **VS Code**. It also includes instructions for programming the chip using an **FT232 USB-UART adapter** via the UPDI interface with `pymcuprog`.  
+
+---
+
+## Table of Contents
+
+- [Dependencies](#dependencies)
+- [Setup Build Environment](#setup-build-environment)
+- [Building the Project](#building-the-project)
+- [Flashing the Firmware](#flashing-the-firmware)
+- [Reading Flash Content](#reading-flash-content)
+- [Hardware Setup](#hardware-setup)
+- [License](#license)
+
+---
+
+## Dependencies
+
+Ensure the following tools are installed on your system:
+
+- **GCC AVR toolchain** (supports ATtiny 0/1-series)  
+  ```bash
+  sudo zypper install avr-gcc avr-libc
+    ```
+- **CMake**
+  ```bash
+    sudo zypper install cmake
+    ```
+- **Python 3, pip and venv**
+  ```bash
+    sudo zypper install python3 python3-pip python3-venv
+    ```
+- **VS Code** (optional but recommended)
+- **CMake Tools extension** for VS Code
+
+## Setup Build Environment
+1. Clone the repository:
+   ```bash
+    git clone https://git.mosad.xyz/localhorst/lezyne-rear-light-firmware
+    cd lezyne-rear-light-firmware
+    ```
+2. Configure the CMake project:
+    - Open the folder in VS Code.
+    - Select the AVR-GCC kit in the bottom blue bar.
+    - Run CMake: Configure (from command palette) if it doesn't auto-run.
+
+## Building the Project
+1. Press F7 or Ctrl+Shift+B to build.
+2. Output files are generated in the 'build/' folder:
+- main.elf → ELF executable
+- main.hex → HEX file (flashable)
+- main.bin → BIN file
+
+## Flashing the Firmware
+Hardware: FT232 USB-UART adapter connected to UPDI with a 4.7 kΩ resistor.
+1. Create and activate a Python virtual environment:
+   ```bash
+    python3 -m venv pyupdi-env
+    source pyupdi-env/bin/activate
+    ```
+2. Install pymcuprog inside the environment:
+   ```bash
+    pip install pymcuprog
+   ```
+3. Verify installation:
+   ```bash
+    pymcuprog --version
+   ```
+4. Flash using pymcuprog:
+   ```bash
+    pymcuprog -t uart -u /dev/ttyUSB0 -d attiny202 write -f build/main.hex
+   ```
+## Hardware Setup (FT232 → ATtiny202 UPDI)
+   ```bash
+    FT232 TX ----[4.7kΩ]---- UPDI (pin 6)
+    FT232 GND --------------- GND
+    VCC -------------------- VCC (3.3V or 5V, must match FT232 logic)
+   ```
+
+## License
+
+This project is licensed under the MIT License. See [LICENSE](./LICENSE) for details.