Ble advanced-Link Layer

The link layer of BLE consists of one or more state machines, which are in the middle of five states: standby (standby), advertise (broadcast), scan (SCAN ), init (initialization), connect (connection ).

1.

The upper layer of the link layer is the ble host (host), and the lower layer is the physical layer (modulation and demodulation, RF, etc ).

2.

From the air channels, ble channels are divided into two types: broadcast channels and data channels.

The Broadcast Channel has three frequencies and the data channel has 37.

Note: ble has 40 channels, spanning MHz ~ 2480 MHz, with a bandwidth of 2 MHz for each channel.