A professional-grade SD card testing tool built with ESP32, featuring OLED display, battery monitoring, and comprehensive card diagnostics.

Features

• SD Card Validation
  • Read/write functionality test
  • Full card capacity verification
  • File system integrity check
• Advanced Diagnostics
  • Card type detection (SD/SDHC/MMC)
  • Storage capacity measurement
  • Used/free space analysis
• Safety Features
  • Format confirmation dialog
  • Recursive directory formatting
  • Battery level monitoring (3.2V-4.2V range)
• User Interface
  • OLED display menu system
  • Progress bar animations
  • Audible feedback via buzzer
  • Two-button navigation

Check out the device on YouTube:

https://www.youtube.com/shorts/YD2RQvFlCi8

Hardware Requirements

Component	Specification
Microcontroller	ESP32 Dev Board
SD Card Module	SPI Interface (3.3V logic)
Display	128x64 OLED (SSD1306, I2C)
Battery Monitor	Voltage divider (10kΩ + 20kΩ)
Buttons	2x Tactile switches
Buzzer	Passive piezo buzzer

Installation

Software Requirements

1. Arduino IDE 1.8.19+
2. Required Libraries:
   • SD (Built-in)
   • SPI (Built-in)
   • SSD1306Wire (OLED display)

Hardware Connections

ESP32	SD Card Module	OLED Display	Other
GPIO5	CS
GPIO23	MOSI
GPIO18	CLK
GPIO19	MISO
GPIO21		SDA
GPIO22		SCL
GPIO25			Buzzer
GPIO12			Button A
GPIO14			Button B
GPIO34			Battery ADC

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Usage

Workflow

Initialization Insert SD card Hold Button A to begin System performs automatic detection Testing Phase Write verification (test file creation) Read verification (file contents check) Capacity validation Menu System Button A: Show card info Card type Total capacity Used/free space Button B: Format card Confirmation dialog Full recursive format Visual progress indicator Battery Monitoring

Real-time voltage measurement Percentage estimation (3.2V-4.2V range) Low battery warning system Troubleshooting

Issue Solution SD Card Not Detected Check SPI connections Formatting Fails Verify card physical switch Inaccurate Battery % Confirm resistor values Display Not Working Verify I2C address (0x3C) False Test Failures Try different SD card License

This project is licensed under the MIT License - see LICENSE for details.