The Bluetooth® Low Energy (BLE) link layer on the BM71 operates in a variety of states which are analogous to those described in the standard. This page provides an overview of these connection states, which will help you to understand the device datasheet electrical specifications.
BLE Connection Phases
In a BLE connection establishment, both hosts run through a sequence of basic connection phases, as shown in the diagram:
| Connection Phase | Overview |
|---|---|
| Standby/Idle | No connection |
| Discovery | Slave (Advertiser) sends ADV packets and is discoverable |
| Connecting | Master (Initiator) selects a device to connect to |
| Connected | Master/Slave exchange data packets at regular intervals |
BLE Link Layer States
These connection phases correspond to link layer states as defined in the Bluetooth standard:
BM71 Link Layer States
BM71 defines its own link layer operating states that are analogous to those defined above:
| BM71 LL State | Corresponds To | Connection Phase |
|---|---|---|
| Shutdown | - | Lowest Power mode (BM71 is Shutdown) |
| Idle | Standby | No connection |
| Standby | Advertising | Discovery |
| Scanning | Scanning | Discovery |
| Connecting | Initiating | Connecting |
| Connected | Connected | Connected |
BM71 defines different labels for some of the basic BLE link layer states. This page outlines these differences, and will help you better understand the electrical specifications in the device datasheet.