10.3. How to use the peripheral only mode
The peripheral only mode is enabled, when a high signal is present on the
pin
during device start-up or reset.
No configuration of the module is needed for this operating mode. The module shall be set
to factory settings if reconfigured before so it uses the default user settings. In this case, the
UART uses 115200 Baud 8n1 and static passkey pairing is used as authentication method.
If a configuration of the module is still needed (e.g. when another UART baud rate needs
to be chosen), the module has to be started in normal mode and the
may be
used to update the user settings.
It is permitted to modify any user setting to change the behavior of the peripheral only mode.
Nevertheless, we recommend to update only the following parameters to run the device in
factory state with minimal adaptions:
•
(change the UART baud rate, default value "115200")
•
(change the default static passkey, default value "123123")
•
and
(determine the content of the advertising
packet)
10.4. More information
10.4.1. Radio
In factory state the following holds.
• In peripheral only mode a new 8-digit device name is automatically generated by
the
. In case of the
equals 0x0018DA123456 the device name is
"A-123456". This is a workaround for iOS, which does not allow access to the BTMAC
for received Bluetooth
®
frames.
• The content of the advertising packet was changed in peripheral only mode. The TX
power information block was removed, as the device name was extended to 8 digits.
See also the user setting
to adapt the content of the advertising pack-
et.
10.4.2. UART
• The data sent to the UART is buffered in the Proteus-III up to a maximum payload of
1015 Bytes. When no new Byte was received for 20ms, the data will be transmitted
by radio to the connected Bluetooth
®
LE device. If the data is larger than the MTU
of the connection, the data is sent via radio in several packets, with one packet per
connection interval.
• To enable a fast transmission of data packets a large MTU of the Bluetooth
®
LE connec-
tion is helpful. The Proteus-III supports up to 243 Bytes Bluetooth
®
LE packet payload
(corresponding to a MTU of 247 Bytes), which may be negotiated by the central device
(using a MTU request). If no MTU request is requested by the connecting central de-
vice the value of 19 Bytes payload per Bluetooth
®
LE packet and connection interval
Proteus-III reference manual version 1.3
© August 2020
www.we-online.com/wireless-connectivity
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