HM-12 4.0 Dual mode bluetooth module , BLE SPP LE serial port , V4.0 EDR + BLE dual mode HM-12 is Bluetooth V4.0 BLE version. Use TI Chip. BT Version: Bluetooth Specification V4.0 EDR and BLE Send and receive maximum byte count is 90 bytes. Working frequency: 2.4GHz ISM band Modulation method: GFSK(Gaussian Frequency Shift Read more about HM-12 4.0 Dual mode bluetooth module , BLE SPP LE serial port , V4.0 EDR + BLE dual mode[…]