BLEMDL-2 is a BLE data transmission module, based on (ARM Cortex-M0 32-bit processor, up to 64MHz working frequency) with 256KB Flash and 48KB RAM, features a high performance 2.4GHz transceiver, equipped with an on-board PCB antenna and the external antenna is optional with connector. The module communicates with an external MCU via UART to quickly set up wireless connection and data transfer between BLE peripheral devices and BLE central devices (such as mobile phones and tablets). The external MCU has a low resource occupation and makes it easy for the developer to solve complex wireless communication challenges and accelerate time to market.