The BT12 is a compact dual-mode Bluetooth module based on the JDY chipset, supporting both Bluetooth 2.0 (SPP) and Bluetooth Low Energy (BLE 4.0). It enables seamless wireless serial communication with mobile devices and embedded systems, making it ideal for IoT, automation, and remote control applications.

Specifications

• Bluetooth Version: Dual-mode (Classic 2.0 + BLE 4.0)
• Chipset: JDY-12 or JDY-10 variant (BT12 label)
• Operating Voltage: 3.3 V DC
• Logic Level: 3.3 V (requires level shifting for 5 V MCUs)
• Communication Interface: UART (TXD, RXD)
• Default Baud Rate: 9600 (configurable via AT commands)
• Supported Profiles:
  - SPP (Serial Port Profile) for Android and PC
  - BLE GATT for iOS and BLE hosts
• Role: Slave only (cannot initiate connections)
• Range: ~10–20 m (open space)
• Antenna: Onboard PCB antenna
• Dimensions: ~27 mm × 13 mm
• Pinout:
  - VCC, GND
  - TXD, RXD
  - STATE (connection status)
  - EN (key pin for AT mode)
• Packaging: Bare module (no adapter board or regulator)

Features

• Dual-mode Bluetooth for compatibility with both Android (SPP) and iOS (BLE)
• AT command support for name, baud rate, and UUID configuration
• Compact and lightweight for embedded PCB designs
• Ideal for wireless serial communication in IoT and automation systems
• Common use cases:
  - BLE sensor nodes and wearable electronics
  - Smartphone-controlled Arduino projects
  - Wireless UART bridges and automation systems
  - DIY BLE beacons and remote controls