# Gemini Chat Gadget for ESP32-C6-LCD-1.69

This project builds a minimal ESP-IDF application that turns an ESP32-C6-LCD-1.69 board into a Gemini chat gadget. It features on-screen state indicators, speaker beeps, Wi-Fi connectivity, and integration with the Gemini API.

## Hardware

*   **MCU/Board:** ESP32-C6 DevKitC-1
*   **Display:** 1.69" ST7789V2, 240x280 resolution, SPI interface
*   **Default Pins (configurable via Kconfig):**
    *   MOSI: GPIO7
    *   SCLK: GPIO6
    *   CS: GPIO5
    *   DC: GPIO2
    *   RST: GPIO4
    *   BL (Backlight): GPIO15
    *   BUTTON: GPIO0
    *   LED: GPIO8
    *   SPEAKER: GPIO25
    *   BAT_EN (Battery Enable): GPIO15 (drive HIGH on battery)

## Features

*   **Display Auto-Probe:** Automatically detects and configures the ST7789V2 display by trying common rotations, offsets, and SPI clock frequencies.
*   **UI State Machine:** Visual feedback on the LCD for different states: BOOT, CONNECTING, READY, LISTENING, THINKING, SPEAKING, and ERROR.
*   **Wi-Fi Connectivity:** Connects to a specified Wi-Fi network in STA mode.
*   **Gemini API Integration:** Communicates with the Google Gemini API (gemini-1.5-flash model) to generate text responses.
*   **Audio Feedback:** Uses LEDC to generate tones for listening and speaking states, and a short beep for thinking.
*   **Button Input:** A button on GPIO0 triggers a chat cycle.
*   **Battery Management:** Sets `BAT_EN` (GPIO15) HIGH to enable battery power.

## Project Structure

*   `CMakeLists.txt`: Main project CMake file.
*   `main/CMakeLists.txt`: Component CMake file for the `main` component.
*   `main/main.c`: Main application source code.
*   `main/Kconfig.projbuild`: Defines Kconfig options for Wi-Fi credentials, Gemini API key, and LCD pin overrides.
*   `sdkconfig.defaults`: Default configuration settings, including UART console, FreeRTOS tick rate, and placeholders for Wi-Fi and Gemini API key.

## Build and Flash Instructions

1.  **Set the ESP-IDF Target:**
    ```bash
    idf.py set-target esp32c6
    ```

2.  **Configure Project Settings:**
    Run `menuconfig` to set your Wi-Fi SSID, Wi-Fi Password, and Gemini API Key. You can also override default LCD pin assignments here if needed.
    ```bash
    idf.py menuconfig
    ```
    Navigate to "Application Configuration" to find the Wi-Fi and Gemini API key settings.
    Navigate to "Application Configuration" -> "LCD Pin Configuration" to adjust pin assignments.

3.  **Build, Flash, and Monitor:**
    This command will build the project, flash it to your ESP32-C6 board, and open a serial monitor to view logs.
    ```bash
    idf.py build flash monitor
    ```

## Acceptance Criteria

*   Upon boot, the LCD should display a color-sweep during the auto-probe routine, followed by the BOOT, CONNECTING, and READY states.
*   Pressing the button should initiate the LISTENING state (with a tone), transition to THINKING (with a beep), perform an HTTP POST to the Gemini API, move to SPEAKING (with a tone) while logging the reply, and finally return to the READY state.
*   The console logs should clearly show auto-probe attempts and results, Wi-Fi connection status, HTTP status codes, and the extracted Gemini text response.
*   The application should handle Wi-Fi or HTTP failures gracefully, transitioning to an ERROR state with appropriate logging.

## Dependencies

The project is designed to be lightweight and uses the following ESP-IDF components:

*   `esp_lcd`
*   `esp_http_client`
*   `cJSON`
*   `esp_wifi`
*   `driver` (for GPIO and LEDC)
*   `esp_timer`