Design

Communication

Lenovo HW01 smart watch uses Bluetooth LE for communication. It is done through write/notification mecanism.

  • RX

Bluetooth characteristic 00000003-0000-1000-8000-00805f9b34fb is used to emit command from host to device. You will use this channel to write commands.

  • TX

Device answers to host requests by sending back response in form of notification on Bluetooth characteristic 00000004-0000-1000-8000-00805f9b34fb, thus no explicit read is needed.

Note: Notifications for its Client Characteristic Configuration descriptor need to be enabled in order to receive responses.

Authentication

No authentication, nor authorization is requested to establish communication beetween host and device.

Binding is not permitted when device is already bond to another host.

Commands

Lenovo HW01 smart watch answers to a set of commands. Each command starts with AT+ [1] and is followed by ASCII strings representing:
  • Command name
  • Optional parameters (separated by commas)

Example:

AT+command
Commands can be used to :
  • Request data.
  • Configure the device (In this case “=” sign is used to specifiy arguments).

Example:

AT+command=param1,param2...

Refer to API for detail.

[1]https://en.wikipedia.org/wiki/Hayes_command_set