ST STM32G4 Nucleo-32 User manual

Introduction
The STM32G4 Nucleo-32 board (NUCLEO-G431KB) provides an affordable and flexible way for users to try out new concepts
and build prototypes, by choosing from the various combinations of performance, power consumption and features provided by
the STM32G4 Series microcontroller. The ARDUINO® Nano V3 connectivity provides easy means of expanding the functionality
of the Nucleo open development platform with a wide choice of specialized shields. The STM32G4 Nucleo-32 board does not
require any separate probe as it integrates the STLINK-V3E debugger/programmer. The STM32G4 Nucleo-32 board comes
with the comprehensive free software libraries and examples available with the STM32CubeG4 MCU Package.
Figure 1. NUCLEO-G431KB top view Figure 2. NUCLEO-G431KB bottom view
Pictures are not contractual.
STM32G4 Nucleo-32 board (MB1430)
UM2397
User manual
UM2397 - Rev 2 - September 2019
For further information contact your local STMicroelectronics sales office.
www.st.com

1Features
• STM32G4 microcontroller (Arm® Cortex®-M4 at 170 MHz) in UFQFPN32 package, featuring 128 Kbytes of
Flash memory and 32 Kbytes of SRAM for STM32G431KBT6
• 1 user LED
• 1 RESET push button
• 24 MHz HSE crystal oscillator
• Board connectors:
– USB with Micro-B
–ARDUINO® Nano V3 expansion connector
• Flexible power-supply options: ST-LINK USB VBUS or external sources
• On-board STLINK-V3E debugger/programmer with SWD connector:
– USB re-enumeration capability: virtual COM port, mass storage, debug port
• Comprehensive free software libraries and examples available with the STM32Cube package
Note: Arm is a registered trademark of Arm Limited (or its subsidiaries) in the US and/or elsewhere.
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Features
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2Ordering information
To order the STM32G4 Nucleo-32 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-G431KB MB1430 STM32G431KBT6U
2.1 Product marking
Evaluation tools marked as “ES” or “E” are not yet qualified and therefore not ready to be used as reference
design or in production. Any consequences deriving from such usage will not be at ST charge. In no event, ST will
be liable for any customer usage of these engineering sample tools as reference design or in production.
“E” or “ES” marking examples of location:
• On the targeted STM32 that is soldered on the board (for illustration of STM32 marking, refer to the STM32
datasheet “Package information” paragraph at the www.st.com website).
• Next to the evaluation tool ordering part number that is stuck or silk-screen printed on the board.
This board features a specific STM32 device version, which allows the operation of any bundled commercial
stack/library available. This STM32 device shows a "U" marking option at the end of the standard part number
and is not available for sales.
In order to use the same commercial stack in his application, a developer may need to purchase a part number
specific to this stack/library. The price of those part numbers includes the stack/library royalties.
2.2 Codification
The meaning of the codification is explained in Table 2.
Table 2. Codification explanation
NUCLEO-XXYYKT Description Example: NUCLEO-G431KB
XX MCU series in STM32 Arm Cortex MCUs STM32G4 Series
YY MCU product line in the series STM32G431
K STM32 package pin count 32 pins
BSTM32 Flash memory size:
• B for 128 Kbytes 128 Kbytes
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Ordering information
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3Development environment
3.1 System requirements
• Windows® OS (7, 8 and 10), Linux® 64-bit, or macOS®
• USB Type-A to Micro-B cable
Note: macOS® is a trademark of Apple Inc. registered in the U.S. and other countries.
All other trademarks are the property of their respective owners.
3.2 Development toolchains
• Keil® MDK-ARM (see note)
• IAR™ EWARM (see note)
• GCC-based IDEs
Note: 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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Development environment
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4Conventions
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 should be 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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Conventions
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5Quick start
The STM32G4 Nucleo-32 board is a low-cost and easy-to-use development kit, used to evaluate and start a
development quickly with an STM32G4 Series microcontroller in LFQFPN 32-pin package. Before installing and
using the product, accept the Evaluation Product License Agreement from the www.st.com/epla webpage. For
more information on the STM32G4 Nucleo-32 and for demonstration software, visit the www.st.com/stm32nucleo
webpage.
5.1 Getting started
Follow the sequence below to configure the STM32G4 Nucleo-32 board and launch the demonstration application
(refer to Figure 4 for component location):
1. Check the jumper position on the board (refer to Table 4).
2. For the correct identification of the device interfaces from the host PC and before connecting the board,
install the Nucleo USB driver available on the www.st.com/stm32nucleo website.
3. To power the board, connect the STM32G4 Nucleo-32 board to a PC with a USB cable (Type-A to Micro-B)
through the USB connector CN1 of the board.
4. Then, LED LD1 (COM) and green LED LD4 (5V_PWR) light up, green LED LD2 blinks.
5. Remove the jumper placed between D2 (CN4 pin 5) and GND (CN4 pin 4).
6. Observe how the blinking of the green LED LD2 changes, when the jumper is in place or removed.
7. Download the software demonstration software and several software examples that help to use the STM32
Nucleo features. These are available on the NUCLEO-G431KB webpage
8. Develop your own application using the available examples
Table 4. Jumper configuration
Jumper Definition Position(1) Comment(1)
JP1 IDD ON For STM32G4 current
measurements
1. Default jumper state is in bold.
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Quick start
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6Hardware layout and configuration
The STM32G4 Nucleo-32 board is designed around the STM32 microcontrollers in a 32-pin UFQFPN package.
Figure 3 shows the connections between the STM32 and its peripherals (STLINK-V3E, push button, LEDs, USB
and Arduino Nano). Figure 4 and Figure 5 show the location of these features on the STM32G4 Nucleo-32 board.
The mechanical dimensions of the board are shown in Figure 6.
Figure 3. Hardware block diagram
Connector
or jumper
STLINK-V3E Part
STM32G431KB
SWD VCP
UART
GPIOs
GPIOGPIO
B1
button
RESET
ARDUINO® NANO
GPIO
ARDUINO® NANO
IDD
Bicolor
LED
LD1
(COM)
OSC
24 MHz
Crystal
Red LED
LD3 (OC)
Green LED
LD2 (USER)
Green LED
LD4
(5V_PWR)
USB
Micro-B
connector
(CN1)
25 MHz
Crystal
STLK
MCO
Embedded
STLINK-V3E
SWD VCP
UART
XXX
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Hardware layout and configuration
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6.1 PCB layout
Figure 4. Top layout
U1 Main CPU
(STM32G431KBT6)
CN1
STLINK-V3E Micro-B
USB connector
CN2
SWD connector (not fitted)
LD2 green LED (USER)
LD4 green LED (5V_PWR)
B1 green RESET button
LD1 bicolor LED (COM)
X1 25 MHz oscillator
X2 24 MHz HSE crystal
LD3 red LED (Overcurrent)
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PCB layout
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Figure 5. Bottom layout
CN1
STLINK-V3E Micro-B
USB connector
U4 Common mode
filter with ESD
protection for USB
HW1 (2.54 mm
jumper) on CN4 [4-5]
U7
5V_USB_STLK regulator
STMPS2151STR
CN4
ARDUINO® Nano
connector
JP1 (1.27 mm jumper) for
IDD measurement
HW2 (1.27 mm jumper)
fitted on JP1 [1-2]
CN3
ARDUINO® Nano
connector
U6 3V3_STLK regulator
LD3985M33R
U8 5V_VIN regulator
LD1117S50TR
U9 3V3 regulator
LD39050PU33R
U5 STM32F723IEK6
(STLINK-V3E MCU)
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PCB layout
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6.2 Mechanical drawing
Figure 6. STM32G4 Nucleo 32 board mechanical drawing (in millimeter)
18.542 mm
50.292 mm
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Mechanical drawing
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6.3 Embedded STLINK-V3E
The way to program and debug the onboard STM32 MCU is by using the embedded STLINK-V3E.
The STM32G4 Nucleo-32 integrates the STLINK-V3E programming and debugging tool.
The embedded STLINK-V3E supports only SWD and VCP for STM32 devices. For information about debugging
and programming features, refer to the STLINK-V3SET debugger/programmer for STM8 and STM32 user manual
(UM2448), which describes in details all the STLINK-V3E features.
Features supported on STLINK-V3E:
• 5V power supplied by USB connector (CN1)
• USB 2.0 high-speed-compatible interface
• Serial wire debugging (SWD) specific features:
– 3 V to 3.6 V application voltage on the SWD interface and 5 V tolerant inputs
– Serial viewer (SWV) communication
• Status LD1 LED (COM), blinking during communication with the PC
• Fault red LED LD3 (OC), alerting on USB overcurrent request
• 5 V / 300 mA output power supply capability (U4), with current limitation and LED
• 5 V power green LED LD4 (5V_PWR)
6.3.1 Drivers
Before connecting the STM32G4 Nucleo-32 board to a Windows PC via USB, the user must install a driver for the
STLINK-V3E (not required for Windows 10). It is available at the www.st.com website.
In case the STM32G4 Nucleo-32 board is connected to the PC before the driver is installed, some STM32G4
Nucleo-32 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 7.
Note: Prefer using the USB Composite Device handle for a full recovery.
Figure 7. USB composite device
Note: 37xx:
• 374E for STLINK-V3E without bridges functions
• 374F for STLINK-V3E with bridges functions
6.3.2 STLINK-V3E firmware upgrade
The STLINK-V3E embeds a firmware upgrade mechanism for in-situ upgrade through the USB port. As the
firmware may evolve during the lifetime of the STLINK-V3E 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 STM32G4 Nucleo-32 board and periodically, to stay up-to-date with the latest firmware version.
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Embedded STLINK-V3E
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6.4 Power supply
Five different sources can provide the power supply:
•A host PC connected to CN1 through a USB cable (default setting)
• An external 5 V USB charger (5V_USB_CHGR) connected to CN1
• An external 7 V - 12 V (VIN) power supply connected to CN3 pin 1
• An external 3.3 V power supply (3V3) connected to CN3 pin 14
• An external 5 V power supply (5V) connected to CN3 pin 4
Figure 8. STM32G4 Nucleo-32 board power tree
STLINK-V3E USB connector (CN1)
ARDUINO®
Nano
Connector
STM32F723IEK
(STLINK-V3E)
and
bicolor LED LD1 (COM)
DFU connector (CN2)
MCU STM32G4
LDO
LD39050PU33R
3V3
5V
U9
U7
LDO
LD3985M33R
U6
5V_USB_STLK
5V_VIN
LDO
LD1117S50TR
U8
VIN
5V
5V_VIN
3V3
5V_VIN
5V_USB_CHGR
3V3_STLK
AVDD
VDD
3V3
5V
Power switch 5V/0.5A
STMPS2151STR
5V_USB_CHGR
5V_VIN
(VDD)
VDD
SB5 (ON)
JP1
ON
AVDD
(AVDD)
CN4
1
CN3
1
1515
In case VIN, 5V or 3V3 is used to power the STM32G4 Nucleo-32 board, this power source must comply with the
EN-60950-1: 2006+A11/2009 standard and must be Safety Extra Low Voltage (SELV) with limited power
capability.
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Power supply
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If the power supply is 3V3 or 5V, the ST-LINK is not powered and cannot be used.
1) Power supply input from STLINK-V3E USB connector (default setting)
The STM32G4 Nucleo-32 board and shield can be powered from STLINK-V3E connector CN1 (5 V).
If the USB enumeration succeeds, the 5V_USB_STLK power is enabled, by asserting the T_PWR_EN signal from
STM32F723IEK6 "STLINK V3" (U5). This pin is connected to a power switch STMPS2151STR (U7), which
powers the board. The power switch STMPS2151STR (U7) features also a current limitation to protect the PC in
case of short-circuit on board. If an overcurrent (more than 500 mA) happens on board, the red LED LD3 (OC as
Over Current) is lit.
The Nucleo board and its shield can be powered from ST-LINK USB connector CN1, but only ST-LINK circuit gets
power before USB enumeration, because the host PC only provides 100 mA to the board at that time.
During the USB enumeration, the Nucleo board requires 500 mA power from the host PC.
• If the host is able to provide the required power, the enumeration finishes by a SetConfiguration command.
Then, the power switch STMPS2151STR is switched ON, the green LED LD4 (5V_PWR) is turned ON, thus
Nucleo board and its shield on it can consume 500 mA at the maximum.
• If the host is not able to provide the requested current, the enumeration fails. Therefore, the
STMPS2151STR power switch (U7) remains OFF and the MCU part including the extension board is not
powered. Therefore, the green LED LD4 remains turned OFF. In this case, it is mandatory to use an external
power supply.
Caution: If the maximum current consumption of the STM32G4 Nucleo-32 board and its shield boards exceeds 300 mA, it
is either mandatory to check the root cause of the overconsumption, and consequently (if needed) to power the
STM32G4 Nucleo-32 board with an external power supply connected to VIN, 5V or 3V3.
2) External power supply input from USB charger (5 V)
In case a USB charger powers the board, there is no USB enumeration. The target is powered anyway.
3) External power supply input from VIN (7 V - 12 V, 800 mA max)
The STM32G4 Nucleo-32 board and its shield boards can be powered in three different ways from an external
power supply, depending on the voltage used. The three cases are summarized in Table 5.
Table 5. External power sources: VIN (7 V - 12 V)
Input power
name
Connector
pins Voltage range Maximum current Limitation
VIN CN3 pin 1 7 V to 12 V 800 mA
From 7 V to 12 V only and input current capability is
linked to input voltage:
• 800 mA input current when VIN = 7 V
• 450 mA input current when 7 V < VIN < 9 V
• 250 mA input current when 9 V < VIN < 12 V
4) External power supply input from external 3.3 V
When a shield board provides the 3.3 V, it is interesting to use the 3V3 (CN3 pin 14) directly as power input (refer
to Table 4). In this case, the programming and debugging features are not available, since the ST-LINK is not
powered.
Table 6. External power sources: 3V3
Input power name Connector pins Voltage range Maximum current
3V3 CN3 pin 14 3 V to 3.6 V 1.3 A
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Power supply
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5) External power supply input from external 5 V
When a shield board provides the 5 V, it is interesting to use the 5V (CN3 pin 4) directly as power input (refer to
Table 7). In this case, the programming and debugging features are not available, since the ST-LINK is not
powered.
Table 7. External power sources: 5V
Input power name Connector pins Voltage range Maximum current
5V CN3 pin 4 4.75 V to 5.25 V 500 mA
6.4.1 Debugging while using VIN or EXT as an external power supply
When powered by VIN or 5V, it is still possible to use the ST-LINK for programming or debugging only, but it is
mandatory to power the board first using VIN or EXT (either 3V3 or 5V), then to connect the USB cable to the PC.
By acting this way, the enumeration succeeds, thanks to the external power source.
The user must respect the following power-sequence procedure:
1. Connect the external power source to VIN or 5V
2. Power on the external power supply 7 V< VIN < 12 V for VIN, or 5 V for 5V
3. Check that the green LED LD4 (5V_PWR) is turned ON
4. Connect the PC to the USB connector CN1
If this order is not respected, the board may be powered by USB first, then by VIN or 5V as the following risks
may occur:
1. If the board needs more than 300 mA current, the PC may be damaged or can limit the current supplied.
Consequently, the board is not powered correctly.
2. Enumeration requests 300 mA, so there is risk that the request is rejected and the enumeration does not
succeed if the PC cannot provide such current. Consequently, the board is not power supplied (LED LD3
remains OFF).
3V3 power supply
Using the 3V3 (CN3 pin 14) directly as power input, can be interesting, for instance, in case a shield provides the
3.3 V. In this case the STLINK-V3E is not powered, thus programming and debugging features are not available.
5V power supply
Using the 5V (CN3 pin 4) directly as power input, can be interesting, for instance, in case a shield provides the
5 V. In this case the STLINK-V3E is not powered, thus programming and debugging features are not available.
External power supply output
When powered by USB or VIN, the 5V (CN3 pin 4) can be used as output power supply for an ARDUINO® Nano
shield. In this case, the user must respect the maximum current of the power source specified in “External power
sources” table.
The 3V3 (CN3 pin 14) can be used also as power supply output. The maximum current capability of the
LD39050PU33R regulator U9 (500 mA max) limits the available current.
6.5 Clock sources
There are four ways to configure the high-speed clock to use.
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Clock sources
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Figure 9. STM32G431KB Nucleo-32 board clock configuration
•HSI configuration (default): In that case, no external clock is used. The clock is coming from the
STLM32G4 microcontroller. The configuration is:
– SB9 and SB10 OFF
– SB11 and SB8 OFF
– SB13 OFF
•HSE bypass configuration (from ST-LINK): The input clock is the ST-LINK MCO output. The frequency is
fixed to 25 MHz, and connected to the PF0-OSC_IN of the STM32G4 microcontroller. The configuration
must be:
– SB9 and SB10 OFF
– SB11 and SB8 OFF
–SB13 ON
•HSE bypass configuration (from ARDUINO® D7): The clock is coming from an external oscillator through
the pin PF0 (ARDUINO® D7 pin 10 of the CN4 connector). The configuration must be:
– SB9 and SB10 OFF
– SB11 OFF and SB8 ON
– SB13 OFF
•HSE oscillator configuration: The clock is provided by an external crystal (X2) available in the PCB. The
X2 crystal has the following characteristics: 24 MHz, 6 pF load capacitance, 20 ppm. The recommendation is
to use NX2016SA-24MHz-EXS00A-CS10820 manufactured by NDK. For typical frequencies and its
capacitors and resistors, refer to the STM32 microcontroller datasheet and to the Oscillator design guide for
STM8S, STM8A and STM32 microcontrollers Application note (AN2867) for the oscillator design guide. The
configuration must be:
–SB9 and SB10 ON
– SB11 and SB8 OFF
– SB13 OFF
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Clock sources
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6.6 Board functions
6.6.1 LEDs
LD1 STLINK-V3 COM LED
The bicolor LED LD1 (green, red) provides information about STLINK-V3E communication status. LD1 default
color is red. LD1 turns to green to indicate that communication is in progress between the PC and the STLINK-
V3E, with the following setup:
• Blinking red: the first USB enumeration with the PC is taking place
• Red LED ON: when the initialization between the PC and STLINK-V3E is complete
• Blinking red or green: during programming and debugging with target
• Orange ON: communication failure
LD2 USER
This green LED is connected to the following STM32G4 I/O:
• PB8, if the configuration is SB7 ON, and SB6 OFF (default configuration)
• PB3, if the configuration is SB7 OFF, and SB6 ON
It is also connected to the ARDUINO® D13 signal.
To light this LED, a high-logic state “1” must be written in the corresponding GPIO PB8 or PB3. A transistor drives
the LED, so its consumption does not affect the VDD STM32G4 power measurement.
LD4 5V_PWR
The green LED indicates that the STM32G4 part is powered, and the 5 V power is available on CN3 pin 4.
LD3 USB power fault (OC, overcurrent)
LD3 indicates that the board power consumption on USB ST-LINK exceeds 500 mA. Therefore, the user must
check the root cause of the overconsumption, and consequently (if needed) power the STM32G4 Nucleo-32
board with an external power supply.
6.6.2 Push button
B1 RESET (button)
This push button is connected to NRST (PG10-NRST) and is used to reset the STM32G4 microcontroller.
6.6.3 Current consumption measurement (IDD)
Jumper JP1, labeled IDD, is used to measure the STM32G4 microcontroller consumption by removing the jumper
and by connecting an ammeter.
• JP1 ON: STM32G4 is powered by 3V3 voltage (default)
• JP1 OFF: an ammeter must be connected to measure the STM32G4 current. If there is no ammeter, the
STM32G4 is not powered.
6.6.4 Virtual COM port (VCP): USART
The STM32G4 Nucleo-32 board offers the possibility to connect a USART interface to the STLINK-V3E.
Table 8. USART2 connection
Solder bridge configuration(1) Feature(1)
SB1, SB12: ON USART2 (PA2/PA3) connected to STLINK-V3E Virtual COM port.
1. The default configuration is in bold
The communication between the target and the MCU is enabled on USART2 to support the Virtual COM port.
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Board functions
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6.7 Solder bridges
All the 16 solder bridges are located on the bottom layer of the STM32G4 Nucleo-32 board.
Table 9. Solder bridge configuration
Solder bridge control Solder
bridge (SB) State(1) Description(1)
T_VCP_TX SB1
ON T_VCP_TX is connected to STM32G4 I/O PA2.
OFF T_VCP_TX is not connected to STM32G4 I/O PA2.
T_VCP_RX SB12
ON T_VCP_RX is connected to STM32G4 I/O PA3.
OFF T_VCP_RX is not connected to STM32G4 I/O PA3.
3.3 LDO output SB15
ON U9 LDO output provides 3.3V.
OFF U9 LDO does NOT provide 3.3V. The user must connect an
external 3.3V source.
SMD ferrite bead L1 SB5
ON SMD ferrite bead L1 shunted. VDDA connected on VDD
voltage supply
OFF SMD ferrite bead L1 on STM32G4 VDDA voltage supply
LD2
SB7
ON The green user LED LD2 is connected to STM32G4 I/O
PB8 (SB7 ON, and SB6 OFF).
OFF The green user LED LD2 is connected to STM32G4 I/O PB3
(SB7 OFF, and SB6 ON).
SB6
ON The green user LED LD2 is connected to STM32G4 I/O PB3
(SB6 ON, and SB7 OFF).
OFF The green user LED LD2 is connected to STM32G4 I/O
PB8 (SB6 OFF, and SB7 ON).
AGND SB16
ON AGND connected to GND. Reserved, do not modify.
OFF AGND not connected to GND.
SB3
ON
STM32 PA15 is connected to CN3 pin 7 for I2C SCL
support on ARDUINO® Nano A5. In such a case, STM32
PA15 does not support ARDUINO® Nano D5 and PA6
must be configured as floating input.
OFF
CN3 pin 7 is used as ARDUINO® Nano analog input A5
without I2C support and CN4 pin 8 is available as ARDUINO®
Nano D5.
SB2
ON
STM32 PB7 is connected to CN3 pin 8 for I2C SDA
support on ARDUINO® Nano A4. In such a case, STM32
PB7 does not support ARDUINO® Nano D4 and PA5 must
be configured as floating input.
OFF
CN3 pin 8 is used as ARDUINO® Nano analog input A4
without I2C support and CN4 pin 7 is available as ARDUINO®
Nano D4.
ARD_A2 SB14
ON ARDUINO® Nano A2 (CN3, pin 10) is connected to STM32G4
I/O PA3.
OFF ARDUINO® Nano A2 (CN3, pin 10) is disconnected to
STM32G4 I/O PA3.
T_SWO on PB3 SB4
ON T_SWO connected to PB3.
OFF T_SWO not connected to PB3.
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Solder bridges
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Solder bridge control Solder
bridge (SB) State(1) Description(1)
HSE CLK selection
SB9
and
SB10
ON HSE provided by external 24 MHz XTAL CLK X2
OFF HSE not provided by external 24 MHz XTAL CLK X2
SB11
ON PF1-OSC_OUT pin connected to PF1 (ARDUINO® Nano,
CN4, pin 11)
OFF PF1-OSC_OUT pin not connected to PF1 (ARDUINO®
Nano, CN4, pin 11)
SB8
ON PF0-OSC_IN pin connected to PF0 (ARDUINO® Nano, CN4,
pin 10)
OFF PF0-OSC_IN pin not connected to PF0 (ARDUINO® Nano,
CN4, pin 10)
SB13
ON PF0-OSC_IN provided by 25 MHz ST-LINK MCO
OFF PF0-OSC_IN not provided by 25 MHz ST-LINK MCO
1. The default SB state is in bold.
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Solder bridges
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7Board connectors
Several connectors are present on the STM32G4 Nucleo-32 board.
7.1 STLINK-V3E USB Micro-B connector CN1
The USB socket CN1 connects the embedded STLINK-V3E to the PC for the programming and debugging
purposes.
Figure 10. USB Micro-B connector CN1 (front view)
Table 10. USB Micro-B connector CN1 pinout
Connector Pin
number
Pin
name Signal name STLINK-V3E MCU pin Function
CN1
1VBUS 5V_USB_CHGR - 5 V power
2DM USB_DEV_HS_CN_N R14 USB diff pair N
3DP USB_DEV_HS_CN_P R15 USB diff pair P
4ID - - -
5GND - - GND
7.2 ARDUINO® Nano V3 connectors
The ARDUINO® connectors CN3 and CN4 are male connectors compatible with the ARDUINO® standard. Most
shields designed for ARDUINO® can fit with the STM32G4 Nucleo-32 board.
The ARDUINO® connectors on the STM32G4 Nucleo-32 board support the ARDUINO® Nano V3.
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Board connectors
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Figure 11. ARDUINO® connectors
CN4
ARDUINO® Nano
connector
CN3
ARDUINO® Nano
connector
The related pinout for ARDUINO® connector appears in Figure 12 and is listed in Table 11.
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ARDUINO® Nano V3 connectors
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