NINA-B31 series - Getting Started
UBX-18022394 - R02
Configuration
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Example
•
sps://0012f3000001
A peer can be set up using either the default remote peer command
AT+UDDRP
or dynamically created
using the connect peer command
AT+UDCP
. A connection is closed using
AT+UDCPC
.
☞
The Bluetooth low energy SPS service is enabled by default in NINA-B31 and it accepts incoming
connections by default.
2.3
Client and server
A client initiates a connection and the server accepts an incoming connection.
Figure 2: NINA-B31 as a client connecting to the NINA-B31 server
To configure a client to automatically set up a connection to a server, configure the correct Bluetooth
service and the remote peer. The Bluetooth service controls the type of connection that is requested
(see section 2.4) and the preferred server to connect is defined by the remote peer.
•
Default Remote Peer:
AT+UDDRP
configures server (profile and address) to connect and when to
initiate the connection. Peer is enumerated starting with id 0.
•
Server Configuration:
AT+UDSC
only accepts incoming connection attempts for the configured
server profile. NINA-B31 has the SPS enabled by default.
2.4
2 Mbps physical layer (PHY)
In Bluetooth 5, a new physical layer has been introduced. This physical layer doubles the modulation
rate as compared to Bluetooth 4.2. The change from 1 Mbps to 2 Mbps is done by doubling the symbol
rate; because of this, the bandwidth becomes twice as wide. The Bluetooth low energy already has 2
MHz channel centers so the increased bandwidth does not reduce the number of channels.
•
Preferred Transmitter/Receiver PHY:
AT+UBTLECFG=27/28
sets the preferred PHYs to be used as
response for peer-initiated PHY update requests.
•
Low Energy PHY Request:
AT+UBTLEPHYR
requests a change of PHY for the specified connection.
2.5
Bluetooth services
The Generic Attributes (GATT) is used when Bluetooth LE devices exchange data. There are two roles
defined in GATT – the client and server. For more information about GATT, see [8].
The GATT server stores data received from the GATT client. The GATT server sends responses to
requests and sends indications and notifications to the GATT client when specified events occur on
the GATT server.
Official as well as user-defined GATT Services can be set up with AT commands. The Serial Port
Service (SPS) is a u-blox proprietary serial cable emulation service, which is enabled by default.
