ESP32-WROOM-DA is a powerful Wi-Fi + Bluetooth + Bluetooth LE MCU module, with two complementary PCB antennas in different directions. I customized the 16MB memory version and designed this development board around it. With two antennas design on one single module, ESP32-WROOM-DA can be used to develop IoT applications that need stable connectivity over a broad spectrum, or to deploy Wi-Fi in challenging and hazardous environments, or to overcome communication problems in Wi-Fi-dead spots. This module is an ideal choice for indoor and outdoor devices for smart home, industrial control, consumer electronics, etc. Equipped with a 128x64 dual OLED screen, data monitoring and interactive interface are displayed simultaneously. Equipped with a built-in DS3231 chip (with 2ppm accuracy) and a MicroSD card slot, it ensures precise data recording and massive storage (supporting FAT32/exFAT formats). Integrated 5V/1A Type-C fast charging and lithium battery management (charge and discharge efficiency 85%), power module supports 5-12V wide voltage input, ensuring no power interruption for outdoor projects. The 17 GPIO pins can be connected to sensors, and it is compatible with for the /PlatformIO ecosystem. There are schematic diagrams, test source codes, etc. in the SD card. Please back up the contents of the SD card in advance. GPIOs and hardware Diplay: SH1106 1.3 OLED (0x3D,0x3C) Display SDA: GPIO21 Display SCL: GPIO22 Rotary switch LEFT: GPIO 15 Rotary switch : GPIO 13 Rotary switch RIGHT: GPIO 0 button: GPIO 32 SD :GPIO5 SD MOSI:GPIO23 SD :GPIO19 SD SCLK:GPIO18 DS3231 RTC chip Power/Programming Switch 2 LEDs to indicate battery charging status (Red:Charging,Green:Full) Color: Blue Material: PCB+Components Package Contents: 1 * module 1 * data cable (Data line color is random, specified color is not accepted) 1 * SD card Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.