WIRELESS CONNECTIVITY & SENSORS
User manual Proteus-II
10. Peripheral only mode
The Proteus-II implements a new feature that allows the easy integration of the Proteus-II
Bluetooth
®
LE module to an already existing host. The peripheral only mode offers a plug and
play installation without previous configuration of the Proteus-II. It is tailored for easy commu-
nication with mobile Bluetooth
®
LE devices like smart phones.
The peripheral only mode is a special operation mode, that uses the user settings and the pe-
ripheral functions of the normal mode described in the previous chapters. It has to be enabled
during the module start-up and contains the following key features:
• Peripheral only functions: The Proteus-II only contains the functions of a peripheral. Thus,
it is advertising until another Bluetooth
®
LE device connects to it. In this case, the UART of
the Proteus-II is enabled, the
pin shows that the channel is open and bidirectional
data transmission can start. As soon as the connection is closed, the UART is disabled
again to save power. Since all central functions are no longer valid, the module cannot
initiate any connection or run scans.
• Transparent UART interface: The serial interface of the Proteus-II is no longer driven by
commands. This means, when the UART of the module is enabled (i.e. only when a
channel is open, indicated by both LEDs active), data sent to the UART is transmitted by
the Proteus-II to the connected Bluetooth
®
LE device. On the other hand, all data received
by RF is sent from the Proteus-II to the connected host without additional header Bytes.
The UART is only running, when a channel is open. Thus, power is saved during the
advertising period. Depending on the configured connection interval, only one packet per
interval is allowed to be transmitted. Since the commands of the command interface are
no longer valid, a Proteus-II cannot be configured when running in peripheral only mode.
• Pairing: The default security mode is the static passkey pairing method (see
), with the default key "123123". The bonding feature is enabled by
default.
10.1. Reasons to use the peripheral only mode
The Proteus-II peripheral only mode equips custom applications with a Bluetooth
®
LE interface
(to be accessible by other Bluetooth
®
LE devices) without installation effort.
To setup a connection to the Proteus-II in peripheral only mode the central device has to insert
the Proteus-II’s static passkey. As soon as the channel to a connected Bluetooth
®
LE central
device is open, the
pin switches on to signalize that data can be exchanged now. When
the connection was shut down by the Bluetooth
®
LE central device, the
pin switches off
again.
Due to the transparent UART interface, data can be exchanged without additional headers.
Furthermore, the peripheral only mode allows an energy efficient operation of the Bluetooth
®
LE
interface, since the UART is only enabled when it is really used.
10.2. How to use the peripheral only mode
The peripheral only mode is enabled, when a high signal is present on the
pin dur-
ing device start-up or reset.
Order code 2608011x24010
138
Version 1.11 , July 2022