ST NUCLEO-WB55RG STM32WB User manual

UM2819
User manual
STM32WB Nucleo-64 board (MB1355)
Introduction
The NUCLEO-WB55RG STM32WB Nucleo-64 board based on the MB1355 board is a Bluetooth® Low Energy wireless
and ultra-low-power device embedding a powerful and ultra-low-power radio compliant with the Bluetooth® Low Energy SIG
specification v5.2 and IEEE802.15.4-2011 PHY and MAC is supported.
The ARDUINO® Uno V3 connectivity support and the ST morpho headers provide an easy means of expanding the functionality
of the STM32WB Nucleo open development platform with a wide choice of specialized shields.
Figure 1. NUCLEO-WB55RG top view
Picture is not contractual.
UM2819 - Rev 1 –March 2022
For further information contact your local STMicroelectronics sales office.
www.st.com

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Features
1 Features
•STM32WB55RG (1-Mbytes Flash memory, 256-Kbyte SRAM, in VFQFPN68 package) ultra‑low‑power
wireless microcontroller featuring:
–Dual-core 32‑bit (Arm® Cortex®-M4 and dedicated M0+ CPU for real-time radio layer)
–2.4 GHz RF transceiver supporting Bluetooth® specification v5.2
•Three user LEDs
•One reset and three user push-buttons
•Board connectors:
–ARDUINO® Uno V3 expansion connector
–ST morpho extension pin headers for full access to all STM32WB I/Os
•Integrated PCB antenna and SMA connector footprint
•Flexible power-supply options: ST-LINK, USB VBUS, or external sources
•On-board footprint to mount a CR2032 battery socket
•On-board ST-LINK/V2-1 debugger/programmer with USB re-enumeration capability: mass storage, Virtual
COM port, and debug port
•Comprehensive free software libraries and examples available with the STM32CubeWB MCU Package
•Support of a wide choice of Integrated Development Environments (IDEs) including IAR Embedded
Workbench®, MDK-ARM, STM32CubeIDE
Note: Arm is a registered trademark of Arm Limited (or its subsidiaries) in the US and/or elsewhere.
vd

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Ordering information
2 Ordering information
To order the NUCLEO-WB55RG Nucleo-64 board, refer to Table 1. Additional information is available from the
datasheet and reference manual of the target STM32.
Table 1. Ordering information
Order code
Board reference
Target STM32
NUCLEO-WB55RG
MB1355
STM32WB55RG
2.1 Codification
The meaning of the codification is explained in Table 2.
Table 2. Codification explanation
NUCLEO-XXRYTZ
Description
Example: NUCLEO-WB55RG
XX
MCU series in STM32 32-bit Arm Cortex MCUs
Wireless Bluetooth® STM32WB Series
Y
Product line in the Series
STM32WBx5 product line
R
Product‑specific in the product line:
•1: Die 1, full set of features
STM32WB55 MCU family
T
STM32 package pin count:
•R for 68 pins
68‑pin package
Z
STM32 Flash memory size:
•G for 1 Mbytes
1‑Mbyte Flash memory

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Development environment
3
Development environment
3.1
System requirements
•Multi‑OS support: Windows® 10, Linux® 64-bit, or macOS®
•USB Type-A or USB Type-C® to Micro-B cable
Note:
macOS® is a trademark of Apple Inc. registered in the U.S. and other countries.
Linux® is a registered trademark of Linus Torvalds.
All other trademarks are the property of their respective owners.
3.2
Development toolchains
•IAR Systems® - IAR Embedded Workbench®(1)
•Keil® - MDK-ARM(1)
•STMicroelectronics - STM32CubeIDE
1. On Windows® only.
3.3 Demonstration software
The demonstration software, included in the STM32Cube MCU Package corresponding to the on-board
microcontroller, is preloaded in the STM32 Flash memory for easy demonstration of the device peripherals in
standalone mode. The latest versions of the demonstration source code and associated documentation can be
downloaded from www.st.com.

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Conventions
4 Conventions
Table 3 provides the conventions used for the ON and OFF settings in the present document.
Table 3. ON/OFF convention
Convention
Definition
Jumper JPx ON
Jumper fitted
Jumper JPx OFF
Jumper not fitted
Jumper JPx [1-2]
Jumper fitted between Pin 1 and Pin 2
Solder bridge SBx ON
SBx connections closed by 0 Ω resistor
Solder bridge SBx OFF
SBx connections left open
Resistor Rx ON
Resistor soldered
Resistor Rx OFF
Resistor not soldered

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Safety recommendations
5 Safety recommendations
5.1 Targeted audience
This product targets users with at least basic electronics or embedded software development knowledge such as
engineers, technicians, or students. This board is not a toy and is not suited for use by children.
5.2 Handling the board
This product contains a bare printed circuit board and like all products of this type, the user must be careful about
the following points:
•The connection pins on the board may be sharp, be careful when handling the board to avoid hurting
yourself
•This board contains static sensitive devices. To avoid damaging it, handle the board in an ESD‑proof
environment.
•While powered, do not touch the electric connections on the board with your fingers or anything conductive.
The board operates at a voltage level that is not dangerous, but components may be damaged when
shorted.
•Do not put any liquid on the board and avoid operating the board close to water or at a high humidity level.
•Do not operate the board if dirty or dusty.

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Quick start
6 Quick start
This section describes how to quickly start development using NUCLEO-WB55RG.
To use the product, the user must accept the Evaluation Product License Agreement from the www.st.com/
epla webpage. For more information on the STM32WB Nucleo-64 board and demonstration software, visit the
www.st.com/stm32nucleo webpage.
Before the first use, make sure that no damage has occurred to the board during shipment:
•All socketed components must be firmly secured in their sockets.
•Nothing must be loose in the board blister.
The Nucleo board is an easy-to-use development kit to quickly evaluate and start development with an STM32
microcontroller in a QFN48 package.
6.1 Getting started
Follow the sequence below to configure the STM32WB Nucleo-64 board and launch the demonstration
application (Refer to Figure 3 for component location):
1. Check jumper positions on board: JP2, JP3, JP4, and JP6 ON, JP1 (Power source) on USB_STL, all JP5
jumpers ON except for GND.
2. Install the STMicroelectronics Bluetooth® Low Energy sensor mobile application on a Bluetooth® Low
Energy compatible mobile device from App Store® or Google Play™.
3. Connect the Nucleo board to a PC with a USB Type-A or USB Type-C® to Micro-B cable through CN15 USB
ST-LINK connector. Once powered on, the LD2 green LED blinks for each advertising interval –timeout after
one minute.
4. Use the STMicroelectronics Bluetooth® Low Energy sensor mobile application to detect the STM32WB P2P
server (P2PSRV1) and connect it. Once connected, the LD2 green LED blinks for each connection interval.
The smartphone application displays the device's service and characteristics.
5. Pushing the B1 button on the board toggles the alarm on the smartphone display. Pushing the B2 button
changes the connection interval (50 ms, 1 s). The effect is visible directly on the LD2 green LED of the
Nucleo board. On the smartphone, push the lamp to switch ON or OFF the Nucleo board LD1 blue LED. For
more details, refer to the user manual STM32CubeWB Nucleo demonstration firmware (UM2551).
6. The demonstration software and several software examples showing how to use the STM32 Nucleo features
are available from the NUCLEO-WB55RG product location.

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Hardware layout and configuration
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7 Hardware layout and configuration
The NUCLEO-WB55RG Nucleo-64 board is designed around the STM32WB55RG microcontroller. The hardware
block diagram in Figure 2 illustrates the connection between NUCLEO-WB55RG and its peripherals (ARDUINO®
Uno V3 connector, ST morpho connector, and embedded ST-LINK).
Figure 3 to Figure 5 help the user to locate these features on the NUCLEO-WB55RG board. The mechanical
dimensions of the NUCLEO-WB55RG product are shown in Figure 6.
Figure 2. Hardware block diagram
PCB
Antenna
STLink V2.1
USB
STLink
LDO
5V to 3V
Level Shifter
ESD
Protection
USB
User
ESD
protection
3x LEDs
3x Push Button
Arduino Extension
Connectors
32MHz
Crystal
Morphos Extension Connectors
LDO
5V to 3V
CR2032 Li
Battery
Power Selector
STM32WB55 Filter
Matching
32kHz768
Crystal
LDO
12V to 5V
Board Power
External
Power
Supply
(Optional)
Reset
Push
Button
External
Power
Supply
(Optional)
STM32WB55
Debug
RF Path
GPIOs
Power Managment
MB1355

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Hardware layout and configuration
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Figure 3. NUCLEO-WB55RG PCB top side
Figure 4. NUCLEO-WB55RG PCB with details of the main part (SoC and RF)
ST Restricted
View of STM32WB55RG
after removing the shield,
HSE Crystal (32MHz)
LSE Crystal (32.768KHz)
External Components of SMPS
MLPF-WB55-01E3
(Matching Network & Filter)
U1 STM32WB55RG
ST Restricted
Footprint for
SMA connector
(optional)
PCB Antenna
L1/C37 Matching network
CN5 digital 8-15 ARDUINO®
CN9 digital 0-7 ARDUINO®
CN8 analog 0-5 ARDUINO®
CN6 power ARDUINO®
CN10 MORPHO
CN7 MORPHO
CN15 USB_STLINK
U8 STLINK MCU
LD6 STLINK Status
LD1, LD2, LD3 user LEDs
B1, B2, B3 user push-buttons
B4 Reset push-button
Connector Footprint for
external battery (optional)
LD4 STLink power fault LED
LD5 5V-enable LED
JP1 5V-source selector
JP2 VDD jumper
JP4 VDDRF jumper
JP6 VDDSMPS jumper
JP3 VDD_MCU jumper
JP5 STLINK jumpers
CN1 USB_MCU

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Hardware layout and configuration
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Figure 5. NUCLEO-WB55RG PCB bottom side
ST Restricted
CN15 USB_STLINK SW5 Switch for external power supply
Footprint for CR2032 battery socket
(optional: not assembly by default)
CN1 USB_MCU

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Hardware layout and configuration
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Figure 6. NUCLEO-WB55RG mechanical dimensions (in millimeters)

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Power supply
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7.1 Power supply
7.1.1 General description
By default, the STM32WB55RG microcontroller embedded on this Nucleo board is supplied by 3V3 but the board
proposes a lot of possibilities to supply the device. The 3.3 V can first come from the ST-LINK USB, ARDUINO®,
or ST morpho connectors. Moreover, the STM32WB55RG can be supplied by an external source, between 1.8
and 3.3 V. Thanks to the level shifter, the debug by embedded ST-LINK is always possible even if the supply
voltage of the target is different from 3V3 (ST-LINK supply). Figure 7 shows the power tree. Moreover, this figure
also shows the default state of the jumpers and the solder bridges.
Figure 7. NUCLEO-WB55RG power tree
ST Restricted
USB STLNK (CN15)
Arduino VIN (CN6-8)
MORPHO VIN (CN7-24) LDO 5V STM32WB55RG
LDO 3V3
LDO 3V3
JP1(3-4)
JP1(7-8)
Open
Close
Close VDD
VDDA/VREF+
VDDSMPS
Arduino AVDD (CN5-8)
SB14
SB13
SB17
SB16
Open
Open
Open
STM32F103
(STLINK MCU)
NUCLEO-WB15CC
Ext (CN4-1)
Close
JP2
JP1(1-2)
Open
VBAT
MORPHO 5V_EXT(CN7-6)
U2
Optional CR2032 Socket (CN2) SB19
Open
Close
SB20
JP3
5V
3V3 VDD
SW5
U4
VDD_MCU
Close
Close
Open
Open
SB25
SB27
SB26
SB24
Close
JP6
Close
U3
U5
JP1(5-6)
USB MCU (CN1)
7.1.2 7 to 12 V power supply
NUCLEO-WB55RG can be powered with a 7 to 12 V DC power source. There are three accesses for this type of
DC levels:
1. VIN CN6 pin 8 of the ARDUINO® connector. It is possible to apply until +12 V on this pin or use an
ARDUINO® shield which can deliver this type of voltage on the VIN pin.
2. VIN CN7 pin 24 of the ST morpho connector. It is possible to apply until +12 V on this pin like for the
ARDUINO® connection.
3. CN4 external input. In this case, pay attention to the setting of the jumpers and solder bridges which is very
important. Refer to Table 4.
These sources are connected to the U2 linear low drop voltage regulator. The 5 V output of this regulator is a
potential source of 5V. Refer to Section 7.1.3 for further details.

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7.1.3 5 V power supply
NUCLEO-WB55RG can be powered with a 5 V DC power source. The 5 V can come from several connectors:
1. 5V_USB_STLK connected to CN11 (default configuration for the supply of the board). This connector is
dedicated to the access of ST-LINK/V2 and Virtual COM port and therefore can get supply from the host
computer. It is also possible to connect a USB charger to this connector. In this case, the ST-LINK and the
VCP cannot be accessible.
2. CN4 external input. In this case, pay attention to the setting of the jumpers and solder bridges which is very
important. Refer to Section 7.1.2 for more details.
3. 5V_EXT CN7 pin 6 of ST morpho connector.
4. 7-12V input through the U2 voltage regulator. Refer to Section 7.1.2 for further details.
The JP1 jumper selects the 5V source. Table 4 shows the configuration versus the selected source.
Depending on the current needed by the devices connected to the USB port, and the board itself, power
limitations can prevent the system from working as expected. The user must ensure that the NUCLEO-WB55RG
is supplied with the correct power source depending on the current needed.
Table 4. JP2 power supply selector description
Jumper /
Solder bridge
Setting
Configuration
JP1
5V supply source
selector
NUCLEO-WB55RG is supplied
through CN7pin 6 directly.
NUCLEO-WB55RG is supplied
through the CN6 pin 8 (ARDUINO®) or CN7 pin
24 (ST morpho) orCN4 (Refer to configuration
details in the presentpower supply section).
NUCLEO-WB55RG is supplied
through the CN1 Micro-B USB receptacle
(USB_USER)
Default setting :
NUCLEO-WB55RG is supplied through the CN15
Micro-B USB receptacle (USB ST-LINK)
When 5V_USB_STLINK is used, JP1 is set on [7-8]. The sequence is specific. In the beginning, only STM32F103
is supplied. If the USB enumeration succeeds, the 5V_USB_STLNK power is enabled by asserting the PWR_ENn
signal from STM32F103CBT6. This pin is connected to a TPS2041C power switch which supplies the rest of the
board. This power switch also features a current limitation to protect the host PC in case of currents exceeding
300 mA.

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Power supply
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7.1.4 Current measurement
As the device has low power features, it can be interesting to measure the current consumed by NUCLEO-
WB55RG. To easily do this measurement, there are two possibilities:
1. Measure the supply current of the SoC using an ammeter in place of the JP1 jumper. In this case, all
supply sources can be used except the AVDD coming from the ARDUINO® connector. Figure 8 shows the
configuration.
Figure 8. Current measurement with an ammeter
ST Restricted
USB STLNK (CN15)
Arduino VIN (CN6-8)
MORPHO VIN (CN7-24) LDO 5V STM32WB55RG
LDO 3V3
LDO 3V3
JP1(3-4)
JP1(7-8)
Open
Close
Close VDD
VDDA/VREF+
VDDSMPS
Arduino AVDD (CN5-8)
SB14
SB13
SB17
SB16
Open
Open
Open
STM32F103
(STLINK MCU)
NUCLEO-WB15CC
Ext (CN4-1)
JP2
JP1(1-2)
Open
VBAT
MORPHO 5V_EXT(CN7-6)
U2
Optional CR2032 Socket (CN2) SB19
Open
Close
SB20
JP3
SW5
U4
Close
Close
Open
Open
SB25
SB27
SB26
SB24
Close
JP6
Close
U3
U5
A
+
JP1(5-6)
USB MCU (CN1)

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Clock sources
2. Use an external power supply with current measurement capabilities. In this case, the JP2 jumper must be
removed, and the supply connected to JP2 pin 2, as shown in Figure 9. The supply voltage must be between
1.8 and 3.3 V. AVDD input (CN1 pin 8) must not be used during this measurement.
Figure 9. Current measurement with an external power supply
ST Restricted
USB STLNK (CN15)
Arduino VIN (CN6-8)
MORPHO VIN (CN7-24) LDO 5V STM32WB55RG
LDO 3V3
LDO 3V3
JP1(3-4)
JP1(7-8)
Open
Close
Close VDD
VDDA/VREF+
VDDSMPS
Arduino AVDD (CN5-8)
SB14
SB13
SB17
SB16
Open
Open
Open
STM32F103
(STLINK MCU)
NUCLEO-WB15CC
Ext (CN4-1)
JP2
JP1(1-2)
Open
VBAT
MORPHO 5V_EXT(CN7-6)
U2
Optional CR2032 Socket (CN2) SB19
Open
Close
SB20
JP3
SW5
U4
Close
Close
Open
Open
SB25
SB27
SB26
SB24
Close
JP6
Close
U3
U5
External
Power Supply
1V8 to 3V3
+
-
JP1(5-6)
USB MCU (CN1)
7.2 Clock sources
7.2.1 HSE clock reference
The accuracy of the HSE high‑speed clock of the SoC is committed to a 32 MHz crystal oscillator. The HSE
oscillator is trimmed during board manufacturing.
7.2.2 LSE clock reference
The accuracy of the LSE low‑speed clock of the SoC is committed to a 32.768 kHz crystal oscillator.
7.3 Reset sources
The NUCLEO-WB55RG reset signal is active LOW. The internal pull-up resistor forces the RST signal to a high
level.
The sources of reset are:
•B4 reset push button
•Embedded ST-LINK/V2-1
•CN2 ARDUINO® connector pin 3 (ARDUINO® board reset).
•CN7 ST morpho connector pin 14

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Embedded ST-LINK/V2-1
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7.4 Embedded ST-LINK/V2-1
The ST-LINK/V2-1 programming and debugging tool is integrated into the NUCLEO-WB55RG Nucleo-64 board.
For information about debugging and programming features, refer to the user manual ST-LINK/V2 in-circuit
debugger/programmer for STM8 and STM32 (UM1075), which describes in detail all the ST-LINK/V2 features.
The additional features supported on the ST-LINK/V2-1 are:
•USB software re-enumeration
•Virtual COM port interface on USB
•Mass storage interface on USB
•USB power management request for more than 100 mA power on USB (limited to 300 mA for this board)
The following features are no more supported on the ST-LINK/V2-1:
•Application voltage lower than 3 V
7.4.1 Drivers
The ST-LINK/V2-1 requires a dedicated USB driver, which, for Windows 7®and Windows 8®, is found at
www.st.com. For Windows 10®, it is not necessary to install the driver, as the ST-LINK is automatically identified.
In case the NUCLEO-WB55RG Nucleo-64 board is connected to the PC before the driver is installed, some
board interfaces may be declared as “Unknown” in the PC device manager. In this case, the user must install
the dedicated driver files, and update the driver of the connected device from the device manager as shown in
Figure 10.
Note: Prefer using the “USB Composite Device” handle for a full recovery.
Figure 10. USB composite device
7.4.2 ST-LINK/V2-1 firmware upgrade
The ST-LINK/V2-1 embeds a firmware upgrade mechanism for the in-situ upgrade through the USB port. As the
firmware may evolve during the lifetime of the ST-LINK/V2-1 product (for example new functionalities, bug fixes,
support for new microcontroller families), it is recommended to visit the www.st.com website before starting to use
the NUCLEO-WB55RG Nucleo-64 board and periodically, to stay up-to-date with the latest firmware version.
7.4.3 CN15 ST-LINK/V2-1 USB connector
The main function of this connector is the access to ST-LINK/V2-1 embedded on NUCLEO-WB55RG for
programming and debugging purposes as explained above. It can supply the board (Refer to Section 7.1 Power
supply).

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Embedded ST-LINK/V2-1
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The connector is a standard USB Micro-B connector.
Table 5. USB Micro-B connector CN15 (front view)
Pin
number
Pin name
Signal name
Functions
1
VBUS
5V_USB_ST_LINK
VBUS Power
2
DM
USB_STLK_N
DM
3
DP
USB_STLK_P
DP
4
ID
-
-
5
GND
GND
GND
7.4.4 Virtual COM port: USART1
The STM32WB55RG handles a USB Full Speed peripheral, available on the CN1 USB Micro-B connector.
It can communicate with a USB host as a USB device and can supply the board.
The related pinout of the CN1 USB Micro-B connector is listed in Table 5.
Table 5. USB Micro-B connector CN1(front view)
Pin
number
Pin name
Signal name
Functions
1
VBUS
5V_USB_ST_LINK
VBUS Power
2
DM
USB_STLK_N
DM
3
DP
USB_STLK_P
DP
4
ID
-
-
5
GND
GND
GND
7.4.5 Virtual COM port: USART1
ST-LINK/V2-1 offers a USB Virtual COM port bridge. This feature gives access to the USART1 of the
STM32WB55RG by the CN15 USB ST-LINK connector.
By default, this USART1 interface of STM32WB55RG is connected to the UART2 port of the ST-LINK/V2-1 MCU
(STM32F103).
This VCP can be used differently with an intermediate connection. On the CN14 connector both TX and RX
signals are available and two solder bridges can disconnect the UART coming from SoC.
Table 6. UART interface pinout description
Name
I/O
Wake-up available
USART1 RX (PA10/pin 36)
Pin 1
STLINK_TX: UART2 TX (PA2/pin 12)
USART1 TX (PA9/pin 18)
Pin 2
STLINK_RX: UART2 RX (PA3/pin 13)
7.4.6 Level shifter
NUCLEO-WB55RG has a system to supply STM32WB55RG with a different voltage than ST-LINK. The ST-LINK
is always supplied by 3.3 V sources. By default, STM32WB55RG is supplied by the same voltage value as
ST-LINK, but it is possible to supply the SoC with another value. It accepts a voltage between 1.8 and 3.3 V trust
to a level shifter. This specific component assures the voltage conversion between the ST-LINK and the SoC. It
drives SWD and UART signals connected to VCP on ST-LINK.

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Embedded ST-LINK/V2-1
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7.4.7 JP5 multi‑function jumper
The JP5 multi‑function jumper can connect ST-LINK/V2-1 to STM32WB55RG. It is located between the level
shifter and the SoC. It is referenced to the VDD domain (STM32WB55RG supply voltage domain).
Figure 11. Interconnection bloc diagram between STM32WB55RG and ST-LINK/V2-1
ST Restricted
JP5
Level Shifter
SWD/NRST/UART
(VDD domain)
SWD/NRST/UART
(VDD domain)
SWD/NRST/UART
(3V3_STLINK
domain) STLINK V2.1
STM32WB55RG
U7
VDD 3V3_STLINK
1V8<VDD<3V3
Table 7. Multi-function jumper pinout description
STM32WB55RG
JP5
STM32F103 (ST-LINK)
GND
1-2
GND
NRST (pin 7)
3-4
T_NRST (PB0/pin 18)
SWDIO (PA13/pin 39)
5.6
T_SWDIO (PB12-PB14/pin 25-pin 27)
SWCLK (PA14/pin 41)
7-8
T_SWCLK (PA5-PB13/pin 15-pin 26)
SWO (PB3/pin 43)
9-10
T_SWO (PA10/pin 31)
VDD
11-12
T_VDD
USART1 TX (PA9/pin 18)
13-14
STLINK_RX: UART2 RX (PA3/pin 13)
USART1 RX (PA10/pin 36)
15-16
STLINK_TX: UART2 TX (PA2/pin 12)

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LEDs
7.5 LEDs
Six LEDs on the top side of the Nucleo board help the user during the application development.
Figure 12. LEDs location
ST Restricted
LD6 STLINK Status
LD1, user LED
LD4 STLink power fault LED
LD5 5V-enable LED
LD2, user LED
LD3, user LED
1. LD1: this blue LED is available for user application.
2. LD2: this green LED is available for user application.
3. LD3: this red LED is available for user application.
4. LD4: this LED turns red to indicate that the current distribution cannot be performed as expected when the
board is supplied by USB_STLINK.
5. LD5: this LED turns green when the 5V is available. To select the 5 V source, refer to Section 7.1.3 for
further details.
6. LD6 is a bi-color LED, which default status is red. It turns to green to indicate that communication is in
progress between the host PC and ST-LINK/V2-1 with the following steps:
–Slow blinking red and OFF: at power-on, before USB initialization
–Fast blinking red and OFF: after the first correct communication between the host PC and ST-LINK/
V2-1 (enumeration)
–Red ON: when initialization between the host PC and ST-LINK/V2-1 is successfully finished.
–Green ON: after successful target communication initialization
–Blinking red and green: during communication with the target
–Green ON: communication is successfully finished and OK.
–Orange ON: communication failure.

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Push-buttons
7.6 Push-buttons
7.6.1 Description
NUCLEO-WB55RG provides two types of buttons:
•B1 USER1 pushbutton
•B2 USER2 pushbutton
•B3 USER3 pushbutton
•B4 reset pushbutton to reset the NUCLEO-WB55RG board.
Figure 13. Push-buttons location
ST Restricted
B1, user Pushbutton
B2, user Pushbutton
B3, user Pushbutton
B4, reset Pushbutton
7.6.2 Reset push-button
B4 is dedicated to the hardware reset of the NUCLEO-WB55RG board.
7.6.3 User push-buttons
There are three push‑buttons available for the user application. They are connected to PC4, PD0, and PD1. It is
possible to use them for GPIO reading or to wake up the device (only B1).