ST STM32U5 Nucleo-64 User manual

Introduction
The Nucleo-64 board based on the MB1841 reference board (NUCLEO-U545RE-Q) provides an affordable and flexible way
for users to try out new concepts and build prototypes by choosing from the various combinations of performance and power
consumption features, provided by the STM32U5 series microcontroller.
The ARDUINO® Uno V3 connectivity and the ST morpho headers provide easy expansion of the functionality of the STM32
Nucleo open development platform with a wide choice of specialized shields.
The STM32 Nucleo-64 board does not require any separate probe as it integrates the STLINK-V3EC debugger/programmer.
The STM32 Nucleo-64 board comes with the STM32 comprehensive free software libraries and examples available with the
STM32CubeU5 MCU Package.
Figure 1. Nucleo-64 board (top view)
Picture is not contractual.
STM32U5 Nucleo-64 board (MB1841)
UM3062
User manual
UM3062 - Rev 1 - April 2023
For further information contact your local STMicroelectronics sales office. www.st.com

1Features
• STM32 microcontroller in an LQFP 64‑pin package
• Internal SMPS(1) to generate Vcore logic supply, identified by '-Q' suffixed boards
• USB Type-C® sink device FS
• One user LED shared with ARDUINO® Uno V3
• RESET and USER push-buttons
• 32.768 kHz crystal oscillator
• Board connectors:
–USB Type-C®
–ARDUINO® Uno V3
– ST morpho extension pin headers for full access to all STM32 I/Os
• Flexible power-supply options: ST-LINK USB VBUS, user USB connector, or external sources
• On-board STLINK-V3EC debugger/programmer with USB re-enumeration capability: mass storage, Virtual
COM port, and debug port
• Comprehensive free software libraries and examples available with the STM32CubeU5 MCU Package
• Support of a wide choice of Integrated Development Environments (IDEs) including IAR Embedded
Workbench®, MDK-ARM, and STM32CubeIDE
1. SMPS significantly reduces power consumption in Run mode, by generating a Vcore logic supply from an internal DC/DC
converter.
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 Nucleo-64, 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 Differentiating feature
NUCLEO-U545RE-Q MB1841 STM32U545RET6Q
Microcontroller featuring
512 Kbytes of flash memory
and 274 Kbytes of SRAM
2.1 Products and codification
The meaning of the codification is explained in Table 1.
Table 2. Codification explanation
NUCLEO-XXYYZE-Q Description Example: NUCLEO-U545RE-Q
XX MCU series in STM32 Arm Cortex MCUs STM32U5 series
YY MCU product line in the series STM32U535/U545
ZSTM32 package pin count:
• R for 64 pins 64 pins
ESTM32 flash memory size:
• E for 512 Kbytes 512 Kbytes
-Q STM32 has an internal SMPS function SMPS
The order code is mentioned on a sticker placed on the top or bottom side of the board.
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3Development environment
3.1 System requirements
• Multi‑OS support: Windows® 10, Linux® 64-bit, or macOS®
• USB Type-A or USB Type-C® to USB Type-C® cable
Note: macOS® is a trademark of Apple Inc., registered in the U.S. and other countries and regions.
Linux® is a registered trademark of Linus Torvalds.
Windows is a trademark of the Microsoft group of companies.
3.2 Development toolchains
•IAR Systems® - IAR Embedded Workbench®(1)
•Keil® - MDK-ARM(1)
• STMicroelectronics - STM32CubeIDE
1. On Windows® only.
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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 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
Capacitor Cx ON Capacitor soldered
Capacitor Cx OFF Capacitor not soldered
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5Quick start
The STM32 Nucleo-64 board is a low-cost and easy-to-use development kit, to quickly evaluate and start
development with an STM32U5 series microcontroller in an LQFP 64‑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 STM32 Nucleo-64 board and for the software example, visit the www.st.com/stm32nucleo
webpage.
5.1 Getting started
Follow the sequence below to configure the Nucleo-64 board and launch the demonstration application (refer to
Figure 4 and Figure 5 for component location):
1. Check the jumper position on the board (refer to Default board configuration).
2. Connect the Nucleo-64 board to a PC with a USB cable (USB Type-A or USB Type-C® to USB Type-C®)
through the USB connector (CN1) to power the board.
3. The 5V_PWR green (LD3), COM (LD1), and PWR (LD4) LEDs light up, and the green LED (LD2) blinks.
4. Press the blue user button (B1).
5. Observe how the blinking of the LED (LD2) changes, according to the clicks on the button (B1).
6. Download the demonstration software and several software examples that help to use the STM32
Nucleo-64 features. These are available on the www.st.com website.
7. Develop your application using the available examples.
5.2 Default board configuration
By default, the Nucleo-64 board is configured with VDD_MCU at 3.3 V. It is possible to configure the board with
VDD_MCU at 1.8 V. Before switching to 1.8 V, ensure that the extension module and external shield connected to
the Nucleo-64 board are 1.8 V compatible.
The default jumper configuration and voltage setting are shown in Table 4.
Table 4. Default jumper configuration
Jumper Definition Default position Comment
JP1 Debugger selection OFF STLINK-V3EC is selected as the default
debugger.
JP2 STLK_NRST OFF STLINK-V3EC MCU is not under the
Reset mode.
JP3 5V power selection [1-2] 5V from STLINK-V3EC (STLK)
JP4 IDD measurement ON VDD_MCU current measurement
JP5 VDD [1-2] VDD voltage selection 3.3 V
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Figure 2. Default board configuration
JP3 [1-2]
JP5 [1-2]
3V3
JP4 [1-2]
STM32
microcontroller
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Table 5 explains the different jumper settings and configurations.
Table 5. Jumper configuration
Jumper Definition Setting(1) Comment
JP1 Debugger selection
[1-2]
An external debugger can be used on
the MIPI10 connector (CN4). The level
shifter (U2) is in high-Z. STLINK-V3EC
no longer drives the embedded STM32.
OFF STLINK-V3EC is selected as the
default debugger.
JP2 STLK_NRST
[1-2]
Can be used to reset the STLINK-V3EC
MCU when an external debug probe is
used. Thanks to the U2 level shifter and
JP1, it is not necessary to put STLINK-
V3EC in Reset mode when using an
external debug probe.
OFF Normal mode: Onboard STLINK-V3EC
debugger used
JP3 5V power selection(2)
[1-2] 5V source from STLINK-V3EC (CN1)
[3-4] 5V source from ARDUINO® VIN 7‑12 V
from CN6 or CN7
[5-6] 5V source from external 5V (E5V) from
CN6 or CN7
[7-8] 5V source from ST-LINK in USB charger
mode without USB negociation (CN1)
[9-10] 5V source from user USB Type-C®
(CN3)
OFF No 5V power source. Configuration
applied when external 3.3 V is used.
JP4 IDD measurement
ON VDD_MCU = VDD (3.3 or 1.8 V,
depending on JP5)
OFF
An ammeter is used to measure
VDD_MCU power consumption or a
3.3 or 1.8 V external source can
be connected on pin 2 (STLINK-PWR
tools with STM32CubeMonitor-Power or
ULPBench probe as examples)
JP5 VDD
[1-2] VDD voltage selection is 3V3 power
source.
[2-3] VDD voltage selection is 1V8 power
source
OFF No internal VDD power supply (3.3 or
1.8 V external voltage needed on pin 2)
1. The default configuration is in bold.
2. It is recommended to have only one jumper configuration.
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6Hardware layout and configuration
The STM32 Nucleo-64 board is designed around an STM32U5 microcontroller in an LQFP 64‑pin package.
Figure 3 shows the connections between the STM32 and its peripherals (STLINK-V3EC, push‑buttons, LEDs,
USB, ARDUINO® connectors, and ST morpho headers). Figure 4 and Figure 5 show the location of these
features on the STM32 Nucleo-64 board.
The mechanical dimensions of the board are shown in Figure 6.
Figure 3. Hardware block diagram
STLK-V3EC
STM32 MCU
OSC_32
SWD
32 KHz
crystal
VCP
UART
GPIOs
GPIO
LD2
GPIO
Embedded
STLK-V3EC
SWD
VCP
UART
USB-C®
connector
B1
User B2
RST
ARDUINO®
ST morpho
GPIO
ARDUINO®
ST morpho
5V
PWR SEL
LD3
5V
PWR
JP1 Debug
SEL
JP2 STLK
NRST
STDC14
MIPI10
COM
LS
LS
3V3 / JP5 / 1V8JP4 IDD
USB-C®
connector
ARDUINO®
ARDUINO®
Note: • LS: Level Shifter
• VCP: Virtual COM port
• SWD: Serial Wire Debug
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6.1 Nucleo-64 board layout
Figure 4. Nucleo-64 board top layout
STM32
microcontroller
STLK_NRST
(JP2)
USB STLINK-V3EC
(CN1)
Debugger selection
(JP1)
MIPI10
(CN14)
User button
(B1)
ST morpho connector
(CN7)
IDD jumper
(JP4)
STLK PWR LED
(LD4)
STLK COM LED
(LD1)
5V LED
(LD3)
5V jumper selection
(JP3)
Reset button
(B1)
ST morpho connector
(CN10)
VDD selection 3V3/1V8
(JP5)
ARDUINO® D[7-0]
(CN9)
USB-C® 5V LED
(LD6)
ARDUINO® D[15-8]
(CN5)
USB-C® connector
(CN3)
ARDUINO® ADC
(CN8)
ARDUINO® Power
(CN6)
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Figure 5. Nucleo-64 board bottom layout
SN sticker
CPN sticker
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6.2 Mechanical drawing
Figure 6. Nucleo-64 board mechanical drawing (in millimeters)
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6.3 Embedded STLINK-V3EC
The chapter below gives some information about the implementation of the STLINK-V3EC on this Nucleo-64
board. For details information about ST-LINK capabilities, LED management, driver, and firmware for this
STLINK-V3EC, refer to the technical note Overview of ST-LINK derivatives (TN1235).
For information about the debugging and programming features of STLINK-V3EC, refer to the user manual
STLINK-V3SET debugger/programmer for STM8 and STM32 (UM2448).
6.3.1 Description
There are two different ways to program and debug the onboard STM32 MCU:
• Using the embedded STLINK-V3EC
• Using an external debug tool connected to the STDC14/MIPI10 connector (CN4)
Refer to Table 5. Jumper configuration to switch between STLINK-V3EC and STDC14 configuration.
The STLINK-V3EC facility for debugging and flashing is integrated into the STM32 Nucleo-64.
Features supported in STLINK-V3EC:
•5 V/500m A power supplied by the USB Type-C® connector (CN1)
• USB 2.0 high-speed-compatible interface
• JTAG and Serial Wire Debug (SWD) with Serial Wire Viewer (SWV)
• Virtual COM port (VCP)
• 1.7 to 3.6 V application voltage
• COM status LED which blinks during communication with the PC
• Power status LED which gives information about STLINK-V3EC target power
• USB-C® over‑voltage protection (U5) with current limitation
Two tricolor LEDs (green, orange, and red) provide information about the STLINK-V3EC communication status
(LD1) and STLINK-V3EC power status (LD4). For details information about these LEDs, refer to the technical
note Overview of ST-LINK derivatives (TN1235).
Two level shifters are used on VCP and SWD interfaces to offer a debug capability with MCU powered by a 1.8 V
power source. The level shifters are used for signals from Target MCU (1.8/3.3 V) to STLINK-V3EC (3.3 V).
One of the level shifters is enabled with a jumper called debugger selection (JP1) to isolate the output I/Os from
STLINK-V3EC when an external debug probe is used.
The configuration of this jumper (JP1) to use an external debug probe is explained in Table 5. Jumper
configuration.
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6.3.2 Drivers
The driver installation is not mandatory since Windows® 10 but allocates an ST-specific name to the ST-LINK
COM port in the system device manager.
For details information on the ST-LINK USB driver, refer to the technical note Overview of ST-LINK derivatives
(TN1235).
6.3.3 STLINK-V3EC firmware upgrade
The STLINK-V3EC embeds a firmware upgrade (stsw_link007) mechanism through the USB port. As the
firmware might evolve during the lifetime of the STLINK-V3EC product, to add new functionalities, fix bugs, and
support new microcontroller families, it is recommended to visit the www.st.com website before starting to use the
STM32 Nucleo-64 board and periodically, to stay up-to-date with the latest firmware version.
For details information about firmware upgrades, refer to the technical note Overview of ST-LINK derivatives
(TN1235).
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6.3.4 Using an external debug tool to program and debug the on-board STM32
To support an external debug tool, set the jumper (JP1) to isolate the output I/O from STLINK-V3EC. Then
connect the external debug tool through the STDC14/MIPI10 debug connector (CN4).
When using the external debug connector (CN4), it is possible to use the STLINK-V3EC USB connector (CN1) to
supply the Nucleo-64 board or select another power supply source as described in Section 6.4 Power supply and
power selection.
Figure 7. Connecting an external debug tool to program the on-board STM32 microcontroller
STLK_NRST (JP2) USB STLINK-V3EC (CN1)
Debugger selection (JP1)
MIPI10 (CN4)
STLK PWR LED (LD4)
STLK COM LED (LD1)
STM32
microcontroller
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Figure 8 shows the STDC14/MIPI10 connector (CN4).
Figure 8. STDC14/MIPI10 debug connector (CN4)
STDC14/MIPI10
(CN4)
Table 6. STDC14/MIPI10 debug connector (CN4) pinout describes the STDC14/MIPI10 connector (CN4) pinout.
Table 6. STDC14/MIPI10 debug connector (CN4) pinout
MIPI10 pin STDC14 pin CN4 Function
- 1 NC Reserved(1)
- 2 NC Reserved(1)
1 3 VDD Target VDD(2)
2 4 T_SWDIO Target SWDIO using SWD protocol or target JTMS (T_JTMS) using
JTAG protocol
3 5 GND Ground
4 6 T_SWCLK Target SWCLK using SWD protocol or target JTCK (T_JTCK) using
JTAG protocol
5 7 GND Ground
6 8 T_SWO Target SWO using SWD protocol or target JTDO (T_JTDO) using JTAG
protocol (SB44 ON)(3)
7 9 NC T_JRCLK(4)/NC(5)
8 10 T_JTDI Not used by SWD protocol, target JTDI (T_JTDI) using JTAG protocol
9 11 GNDDetect GND detection for plug indicator(6)
10 12 T_NRST Target NRST using SWD protocol or target JTMS (T_JTMS) using
JTAG protocol
- 13 T_VCP_RX Target RX used for VCP (with UART supporting bootloader)(7)
- 14 T_VCP_TX Target TX used for VCP (with UART supporting bootloader)(2)
1. Not connected on the Nucleo-64 board
2. Output for the Nucleo-64 board
3. SWO is optional and required only for Serial Wire Viewer (SWV) trace.
4. Optional loopback of JTCK on the target side
5. NC means not required for the SWD connection, or not connected on the Nucleo-64 board
6. Tied to GND, it might be used by the external debugger.
7. Input for the Nucleo-64 board
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6.4 Power supply and power selection
6.4.1 External power supply input
It is possible to configure the Nucleo-64 board to use any of the following power sources:
• STLK: 5 V from STLINK-V3EC USB-C® connector (CN1)
• VIN: 7 to 12V from ARDUINO® (CN6) or ST morpho connector (CN7), with 5 V adaptation from LDO (U16)
• E5V: External 5 V power from ST morpho connector (CN7)
• CHGR: 5 V from STLINK-V3EC USB (CN1) without USB enumeration
• USB_USER: 5 V from user USB Type-C® connector (CN3)
•3V3 on ARDUINO® (CN6) or ST morpho connector (CN7).
If VIN, E5V, or 3V3 is used to power a Nucleo-64 board, this power source must comply with the standard
EN‑60950‑1: 2006+A11/2009 and must be safety extra‑low voltage (SELV) with limited power capability.
The power supply capabilities are summarized in Table 7.
Table 7. Power sources capability
Input power name Connector pins Voltage range Max.
current Limitation
STLK CN1
JP3[1-2] 4.75 to 5.5 V 500 mA
The maximum current depends on the presence or
absence of USB enumeration:
• 100 mA without enumeration
• 500 mA with enumeration OK.
VIN / VIN_5V
CN6 pin 8
CN7 pin 24
JP3[3-4]
7 to 12 V 800 mA
From 7V to 12V only and input current capability is
linked to input voltage:
• 800 mA input current when Vin=7V
• 450 mA input current when 7V<Vin<9V
250 mA input current when 9V<Vin<12V
E5V CN7 pin 6
JP3[5-6] 4.75 to 5.5 V 1 A
The maximum current depends on the power
source. 1 A maximum is recommended for this
Nucleo-64 board.
CHGR CN1 pin 1
JP3[7-8] 4.75 to 5.5 V 500 mA
The maximum current depends on the used wall
charger to power the Nucleo-64 board. No USB
enumeration.
USB_USER CN3
JP3[9-10] 4.75 to 5.5 V 1 A
The maximum current depends on the USB Host
used to power the Nucleo-64 board. 1 A maximum
is recommended for this Nucleo-64 board.
3V3 CN6 pin 4
CN7 pin 16 3.0 to 3.6 V -
The maximum current depends on the 3V3 source.
The 3V3 can be used when the STLINK-V3EC part
of the PCB is not used. SB8 might be OFF to
protect LDO (U15).
VDD JP5 pin 2 1.71 to 3.6 V -
It is possible to power only the MCU power
supplies pins by applying a voltage source on JP5
pin 2. In this case, only the MCU is power. External
functions like debug, LED, or expansion connector
are not powered. This option can be used for the
MCU power consumption measurement.
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STLK is a 5 V DC power with limitations from the STLINK-V3EC USB connector (CN1). In this case, the 5V
jumper selection (JP3) must be on pin [1-2] to select the STLK power source on the JP3 connector. This is
the default setting. If the USB enumeration succeeds, the STLK power is enabled, by asserting the T_PWR_EN
signal from STLINK-V3EC. This pin is connected to over‑voltage protection (U5) with the management of the
maximum current delivery.
The Nucleo-64 board and its shield can be powered from the STLINK-V3EC USB connector (CN1), but only the
STLINK-V3EC circuit is powered before USB enumeration because the host PC only provides 100 mA to the
board at that time. During the USB enumeration, the Nucleo-64 board requests 500 mA power from the host PC.
• If the host can provide the required power, the U5 power switch is enabled, the green LED (LD3) is turned
ON, and the Nucleo-64 board and its shield can consume up to 500 mA.
• If the host is not able to provide the requested current, the enumeration fails. the U5 power switch remains
OFF and the MCU part including the extension board is not powered. As a consequence, the green LED
(LD3) remains OFF. In this case, it is recommended to use an external 5 V power source.
STLK configuration: 5V jumper selection JP3[1-2] must be connected as shown in Figure 9.
Figure 9. 5V jumper selection JP3[1-2]: STLK power source
USB STLINK-V3EC
(CN1)
5V LED
(LD3)
5V_STLK selection
(JP3 [1-2])
STM32
microcontroller
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VIN (VIN_5V) is the 7 to 12 V DC power source from the ARDUINO® connector (CN6) pin 8 (VIN), or from
the ST morpho connector (CN7) pin 24. The 5V jumper selection (JP3) must be on pin [3‑4] to select VIN_5V
power source. In that case, the DC power can come from the ARDUINO® Uno V3 battery shield (compatible with
Adafruit PowerBoost 500 shield).
An LDO (U16) is used to provide a fixed 5 V from VIN (7-12V).
VIN_5V configuration: 5V jumper selection (JP3) [3-4] must be connected as shown in Figure 10.
Figure 10. 5V jumper selection JP3[3-4]: VIN_5V power source
ST morpho connector
(CN7 – Pin 24)
ARDUINO® Power connector
(CN6 – Pin 8)
5V LED
(LD3)
VIN/VIN_5V
selection
(JP3 [3-4])
STM32
microcontroller
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E5V is the DC power coming from an external 5 V dc power source from the ST morpho connector (CN7) pin 6.
The 5V jumper selection (JP3) must be on pin [5-6] to select the E5V power source on the JP3 connector and
must be connected as shown in Figure 11. 5V jumper selection JP3[5-6]: E5V power source.
Figure 11. 5V jumper selection JP3[5-6]: E5V power source
ST morpho connector
(CN7 – Pin 6)
5V LED (LD3)
E5V selection
(JP3 [5-6])
STM32
microcontroller
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