Wurth Elektronik ANR004 Proteus User manual

ANR004 PROTEUS
HOW TO USE THE PERIPHERAL ONLY MODE
VERSION 2.4
FEBRUARY 16, 2021

Revision history
Manual
version Notes Date
1.0 • Initial version February 2017
1.1 • Updated MTU size to 247 bytes July 2017
2.0 • New corporate design June 2018
2.1 • Updated product name from AMB2621 to Proteus-I November 2018
2.2
• Updated file name to new AppNote name structure.
Updated important notes, legal notice & license terms
chapters. June 2019
2.3
• Added Proteus-II and Proteus-III description
• Updated address of Division Wireless Connectivity &
Sensors location
January 2020
2.4
• Restructured app note
• Added new chapter Quickstart with new connection setup
examples
• Added information on the Proteus-III mini evaluation board
February 2021
ANR004 Proteus version 2.4 © February 2021
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Abbreviations and abstract
Abbreviation Name Description
BTMAC Bluetooth®conform MAC address of the module used
on the RF-interface.
CS Checksum Byte wise XOR combination of the preceding fields.
DTM Direct test mode Mode to test Bluetooth®specific RF settings.
GAP Generic Access
Profile
The GAP provides a basic level of functionality that all
Bluetooth®devices must implement.
I/O Input/output Pinout description.
LPM Low power mode Mode for efficient power consumption.
LSB Least significant
bit
MAC MAC address of the module.
MSB Most significant bit
MTU Maximum
transmission unit Maximum packet size of the Bluetooth®connection.
Payload The intended message in a frame / package.
RF Radio frequency Describes wireless transmission.
RSSI Receive Signal
Strength Indicator
The RSSI indicates the strength of the RF signal. Its
value is always printed in two’s complement notation.
Soft device Operating system used by the nRF52 chip.
UART
Universal
Asynchronous
Receiver
Transmitter
Allows the serial communication with the module.
[HEX] 0xhh Hexadecimal
All numbers beginning with 0x are hexadecimal
numbers. All other numbers are decimal, unless
stated otherwise.
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Contents
1 Introduction 4
2 Prerequisites 5
3 Peripheral only mode: General information 6
3.1 How to set the Proteus radio module to peripheral only mode? . . . . . . . 6
3.2 General connection setup information . . . . . . . . . . . . . . . . . . . . . 9
3.3 Preconfiguring of the module . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4 Quickstart 12
4.1 Smart phone using nRFConnect app as central device . . . . . . . . . . . . 12
4.2 Smart phone using Proteus Connect app as central device . . . . . . . . . 22
4.2.1 Background service on iOS . . . . . . . . . . . . . . . . . . . . . . 30
4.3 Proteus module or plug as central device . . . . . . . . . . . . . . . . . . . 31
5 References 34
6 Important notes 35
6.1 General customer responsibility . . . . . . . . . . . . . . . . . . . . . . . . . 35
6.2 Customer responsibility related to specific, in particular safety-relevant ap-
plications ..................................... 35
6.3 Best care and attention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
6.4 Customer support for product specifications . . . . . . . . . . . . . . . . . . 35
6.5 Productimprovements.............................. 36
6.6 Productlifecycle ................................. 36
6.7 Propertyrights .................................. 36
6.8 General terms and conditions . . . . . . . . . . . . . . . . . . . . . . . . . . 36
7 Legal notice 37
7.1 Exclusionofliability................................ 37
7.2 Suitability in customer applications . . . . . . . . . . . . . . . . . . . . . . . 37
7.3 Trademarks .................................... 37
7.4 Usagerestriction ................................. 37
8 License terms 39
8.1 Limitedlicense .................................. 39
8.2 Usageandobligations .............................. 39
8.3 Ownership..................................... 40
8.4 Firmwareupdate(s)................................ 40
8.5 Disclaimerofwarranty .............................. 40
8.6 Limitationofliability................................ 40
8.7 Applicable law and jurisdiction . . . . . . . . . . . . . . . . . . . . . . . . . . 41
8.8 Severabilityclause ................................ 41
8.9 Miscellaneous................................... 41
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1 Introduction
The Proteus is a Bluetooth®module based on the nRF52 Nordic Semiconductors SoC which
provides various Bluetooth®LE and low power features.
In addition to the standard command mode, that uses predefined commands to run and
configure the radio module, Würth Elektronik eiSos launches the "peripheral only mode" on
the Proteus to use the module as Bluetooth®LE bridge in a simple way.
In this mode, a Bluetooth®LE interface using the static passkey authentication method (with
bonding) and a transparent UART interface is provided, such that no configuration of the
module is required to equip a custom application with it.
In case the user needs a non-standard configuration, it can be configured in advance using
the command mode, or upon request Würth Elektronik eiSos can apply customer specific
configurations during the production process.
The following chapters describe how to set the module into peripheral only mode and which
steps have to be applied to establish a connection to the radio module.
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2 Prerequisites
• A Proteus evaluation board in factory state, for example
–the Proteus-I evaluation board with firmware version 3.0.0 or newer.
–the Proteus-II evaluation board.
–the Proteus-III evaluation board or mini evaluation board.
• A central device, that initiates the connetion setup. For example
–a smart phone with Bluetooth®LE function and the Nordic Semiconductor nRF
Connect App.
–another Proteus evaluation board or mini evaluation board.
–a Proteus Plug (radio stick containing a Proteus radio module).
Figure 1: Proteus-III evaluation board
To be sure that the Proteus radio module or Proteus Plug is in factory state,
please run a factory reset before doing any other action.
Please check whether the most recent firmware is installed on any Proteus
radio module, EV board or Proteus Plug.
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3 Peripheral only mode: General information
For a better understanding of the content of this chapter, basic knowledge of the Bluetooth®
standard as well as that of the SPP-like profile is of advantage. Please find more details on
that in the respective advanced developer guide:
• ANR002 Proteus-I advanced developer guide
• ANR005 Proteus-II advanced developer guide
• ANR009 Proteus-III advanced developer guide
3.1 How to set the Proteus radio module to peripheral only mode?
The Proteus starts in peripheral only mode, when a HIGH level is applied at the OPERA-
TION_MODE pin and a reset is done via the /RESET pin. If the OPERATION_MODE pin is
LOW during the reset, the module starts in normal operation mode with command interface.
A pull-down is applied to the OPERATION_MODE pin during start-up. Thus
increased currents can occur for a period ≤1 ms.
After the start-up procedure has been finished, the OPERATION_MODE pin
and thus the applied signal level has no function.
For Proteus-III, the OPERATION_MODE pin has been renamed to MODE_1,
while maintaining the same function. Throughout this app note we will use
OPERATION_MODE as a term for this pin.
In case of the evaluation board for Proteus, simply connect the OPERATION_MODE pin to
VCC by setting the respective jumper (see figure 2 , 3 and 4 ). Then press the reset button to
start the module in peripheral only mode.
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Figure 2: On Proteus-I and Proteus-II evaluation board, set these jumpers to start the pe-
ripheral only mode after reset.
Figure 3: On Proteus-III evaluation board, set these jumpers to start the peripheral only mod-
e after reset.
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Figure 4: On Proteus-III mini evaluation board, set these jumpers to start the peripheral only
mode after reset.
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3.2 General connection setup information
In factory state, the peripheral only mode uses the static passkey pairing with bonding au-
thentication method, which requests a static passkey from the connecting device. Figure 5
shows the steps that have to be performed successively during connection setup using the
static passkey pairing method:
1. Physical connection establishment
A physical connection has to be established first. Therefore, a central device (usually
smart phone) has to connect to the Proteus which runs as peripheral.
2. Pairing process
The authentication and exchange of encryption information is part of the pairing pro-
cess. The central device must request at least the same security level to access the
characteristics of the Proteus. The peripheral only mode uses static passkey bonding
by default. The Proteus waits for the bonding request of the central device to perform
this step.
In case the central device goes on with the next steps without placing this bond-
ing request, the peripheral device disconnects immediately as the required
security level is not achieved. The same holds, if the central device places a
bonding request with lower security level than required by the peripheral device
(static passkey with bonding).
3. Exchange of the maximum transmission unit (MTU)
The maximum transmission unit can be increased to allow the transmission of larger
data packets. The Proteus allows an MTU of up to 247 bytes, which results in a payload
of up to 243 bytes. This step is optional. Not selecting a higher MTU will use the
Bluetooth®LE 4.0 default MTU which results in 19 bytes payload for the user but will
be compatible to pre Bluetooth®LE 4.2 devices.
4. Discover the characteristics of the Proteus SPP-like profile
The characteristics offered by the Proteus have to be discovered by the central.
5. Notification enable
The peripheral must let the central know, when there is new data. Therefore, notifica-
tions have to be enabled. After this step, the channel is open and data transmission
can start.
For the description, we assume that a smart phone is the initiator of the connection. Thus, it
acts as central and the Proteus acts as peripheral in figure 5 .
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