Description: Integrates sensor expansion board with HM - 10 4.0. It is fully compatible with keyestudio UNO R3 control board, which can work only through stacking the expansion board on the UNO R3 control board, easy and convenient. It extends all digital ports and analog ports of UNO R3 control board in the form of steering gear sequence. A sensor only needs a universal 3P sensor cable, which is very simple and fast. Expansion board with HM - 10 4.0 can be used for the communication, and toggle switch control the power supply for . There is a jumper cap set on the board, and the default jumper wire achieves the direct communications between module and UNO R3 control board serial port. If the jumper cap connect another two jumper wires, achieving a serial port communication needs the UNO R3 control board to set up the virtual serial port, which needs that the digital port 2 is set to RX, and digital port 3 is set to the TX. Specification: protocol: Specification V4.0 BLE No byte limit in serial port Transceiving In open environment, realize 100m ultra-distance communication USB protocol: USB V2.0 Working frequency: 2.4GHz ISM band Modulation method: GFSK(Gaussian Frequency Shift Keying) Transmission power: -23dbm, -6dbm, 0dbm, 6dbm, can be modified by AT command. Sensitivity: -84dBm at 0.1% BER Transmission rate: Asynchronous: 6K bytes; Synchronous: 6k Bytes Security feature: Authentication and encryption Supporting service: Central & Peripheral UUID FFE0, FFE1 Power consumption: Auto sleep mode, stand by current 400uA~800uA, 8.5mA during transmission. Power supply: 5V DC Working temperature: 5 ~ +65 Centigrade Size: Approx. 12x 8x 4cm/ 4.72x 3.15x 1.57inch Package Includes: 1 Piece Expansion Shield Board