AI-Enhanced TI-84 Plus Calculator Build

TI-84 PLUS + ESP32-S3 + OV5640 AI CALCULATOR BUILDER SPECIFICATION 1. PROJECT OVERVIEW Build a modified TI-84 Plus non-CE calculator with an internally installed Seeed Studio XIAO ESP32-S3 Sense, OV5640 5MP autofocus camera, Wi-Fi, OpenAI API connectivity, TI-84 to ESP32 communication, and a calculator-side AI interface. System architecture: OV5640 camera -> ESP32-S3 -> Wi-Fi -> OpenAI API -> ESP32-S3 -> TI-84 -> Display The ESP32-S3 handles camera control, image processing, networking, and AI communication. The TI-84 provides the keyboard, display, user interface, and commands. Use the existing TI84-AI GitHub project by ivan-grebe as the primary software and architecture reference: https://github.com/ivan-grebe/ti84-ai Do not simply adapt an ESP32-C3 tutorial. This build specifically uses an ESP32-S3, OV5640, and TI-84 Plus. 2. HARDWARE Required hardware: * TI-84 Plus non-CE, fully functioning before modification * Seeed Studio XIAO ESP32-S3 Sense, preferably with sufficient PSRAM * OV5640 5MP autofocus camera compatible with the XIAO ESP32-S3 Sense * Thin insulated hookup wire * Appropriate soldering equipment * Heat-shrink and insulation * Mechanical mounting materials * USB-C cable * Computer for firmware development and flashing Do not permanently close the calculator until all electronics and software have been tested. 3. SYSTEM RESPONSIBILITIES ESP32-S3 responsibilities: * Camera control and image capture * JPEG compression * Base64 encoding * Wi-Fi connection * HTTPS communication * OpenAI API communication * AI request and response handling TI-84 responsibilities: * Keyboard input * Basic user interface * Sending commands to the ESP32 * Displaying AI responses * Scrolling through long responses Preferred image pipeline: OV5640 -> frame buffer -> JPEG -> Base64 -> HTTPS/OpenAI Optimize image resolution, JPEG quality, PSRAM usage, RAM usage, and upload speed. Use a balanced image-quality setting by default, with higher resolution available when small text or equations need to be recognized. 4. TI-84 TO ESP32 COMMUNICATION Use the TI-84's existing 2.5 mm link-port interface for communication, following the established TI84-AI implementation. Reference signal mapping: Tip -> ESP32-S3 D0 Ring -> ESP32-S3 D1 Verify the exact TI-84 board revision, electrical characteristics, voltage levels, and pin functions before soldering. Do not connect unknown signals without verifying their voltage levels and functions. Communication must support: * TI-84 to ESP32 commands * Text transmission * Camera commands * ESP32 to TI-84 responses * Status and error messages * Long responses 5. ESP32-S3 FIRMWARE Use the TI84-AI project as the initial software foundation. Development should use the project's documented environment, including Python, Git, VS Code, and PlatformIO. Compile firmware specifically for the ESP32-S3, not ESP32-C3. Firmware requirements: Wi-Fi Manager: * Configure Wi-Fi SSID * Configure Wi-Fi password * Automatically reconnect after temporary Wi-Fi loss OpenAI Configuration: * Configure the user's OpenAI API credentials * Never hard-code API keys into publicly distributed source code * Make the AI model configurable Camera Configuration: * Allow supported image resolution and quality settings to be changed AI Communication: 1. Capture the camera image. 2. Compress the image to JPEG. 3. Encode the image appropriately. 4. Send the request over HTTPS to the OpenAI API. 5. Receive the response. 6. Parse the response. 7. Send the answer back to the TI-84. Handle Wi-Fi failures, API timeouts, authentication failures, invalid API responses, oversized images, network failures, and empty responses. 6. CAMERA Use the OV5640 5MP autofocus camera. Mount the camera securely inside the calculator with a clear forward-facing view. Test: * Autofocus * Image orientation * Field of view * Lighting * Image sharpness * Text readability * Equation readability The camera must not move during normal handling. If necessary, create a small optical opening or window in the calculator shell. Finalize the camera position only after testing the live image. 7. CALCULATOR-SIDE AI PROGRAM Base the calculator-side program on the existing TI84-AI TI-84 software. Text questions: The user enters a question using the TI-84 keyboard. The calculator sends it to the ESP32. The ESP32 sends it to OpenAI. The response is returned and displayed on the TI-84. Camera questions: The calculator sends a camera command. The ESP32 captures an image with the OV5640. The image is sent to the AI model. The response is returned to the TI-84. Long responses must be scrollable using the TI-84 keypad. Display understandable error messages such as: * Wi-Fi unavailable * API error * Camera error * No response * Configuration required 8. REQUIRED CUSTOM LAUNCHER SEQUENCE The calculator must support this exact launcher sequence. Step 1: 5 -> STOP -> ALPHA -> C -> ENTER Step 2: 2nd -> CATALOG -> LN Step 3: Scroll down to: Send( Press ENTER. Step 4: ALPHA -> C -> ENTER Result: After completing this sequence, the AI application should be accessible through the calculator's normal PRGM menu. Implement this using an appropriate TI-84 program or assembly launcher mechanism. This exact sequence must be tested on the actual TI-84 Plus hardware. Do not assume that Send( will work simply because it appears in the calculator's catalog. The launcher must not interfere with: * Normal calculator operation * Existing programs * Calculator resets * Normal PRGM operation * Keypad functionality 9. RESET AND RAM BEHAVIOR A normal TI-84 RAM reset should return the calculator to a clean normal calculator state while the ESP32-S3 hardware and firmware remain installed. The system must not depend on temporary calculator RAM contents remaining intact. Test: * RAM reset * Calculator power cycle * Battery removal and reinstallation * ESP32 reboot * Wi-Fi loss and reconnection After restarting, the user must be able to invoke the designated launcher again and use the AI