By default:
•
Communication between target MCU and ST-LINK MCU is enabled on LPUART1.
•
Communication between target MCU, ARDUINO
®
and ST morpho connectors is enabled on USART3, not to
interfere with the VCP interface.
The Virtual COM port settings are 115200 bps, 8-bit data, no parity, 1 stop bit and no flow control.
6.13
USB Type-C
™
FS
The STM32 Nucleo-144 board supports USB full-speed (FS) communication. The USB connector CN15 is a USB
Type-C
™
connector.
The STM32 Nucleo-144 board supports USB Type-C
™
SINK mode only.
A green LED LD7 lights up when V
BUS
is powered by a USB host and the NUCLEO-L552ZE-Q board works as a
USB device.
6.13.1
USB FS device
When a USB host connection to the CN15 USB Type-C
™
connector of STM32 Nucleo-144 is detected, the
STM32 Nucleo-144 board starts behaving as a USB device. Depending on the powering capability of the USB
host, the board can take power from the V
BUS
terminal of CN15. In the board schematic diagrams, the
corresponding power voltage line is called 5V_USB_C. The STM32 Nucleo-144 board supports USB voltage 5V:
4.75 V to 5.25 V. MCU VDD_USB supports the 3V3 voltage only.
provides information on how to use
powering options. The hardware configuration for the USB FS interface is shown in
.
Table 12.
HW configuration for the USB interface
IO
HW
Setting
Configuration
PA11
SB137
OFF
PA11 used as USB_FS_N diff pair interface
No other muxing
ON
PA11 can be used as an I/O on the morpho connector.
USB function can be used, but performances are low due to the track
length to the Zio connector: impedance mismatch.
PA12
SB138
OFF
PA12 used as USB_FS_P diff pair interface
No other muxing
ON
PA12 can be used as an I/O on the morpho connector.
USB function can be used, but performances are low due to the track
length to the Zio connector: impedance mismatch.
1. The default configuration is shown in bold.
6.13.2
UCPD
The USB Type-C
™
introduces the USB Power Delivery feature. The STM32 Nucleo-144 supports the dead
battery and the SINK mode.
In addition to the I/O DP/DM directly connected to the USB Type-C
™
connector, 5 I/Os are also used for UCPD
configuration: Configuration Channel (CCx), VBUS-SENSE, UCPD Dead Battery (DBn) and UCPD_FAULT (FLT)
feature.
To protect the STM32 Nucleo-144 from USB over-voltage, a USB Type-C
™
port protection, PPS compliant, is
used: TCPP01-M12 IC compliant with IEC6100-4-2 level 4.
•
Configuration Channel I/O: UCPD_CCx: These signals are connected to the associated CCx line of the USB
Type-C
™
connector through the STM USB port Protection TCPP01-M12. These lines are used for the
configuration channel lines (CCx) to select the USB Type-C
™
current mode. The STM32 Nucleo-144
supports only SINK current mode.
•
Dead Battery I/O: UCPD_DBn: This signal is connected to the associated DBn line of the TCPP01-M12. The
STM USB port Protection TCPP01-M12 managed internally the Dead Battery resistors.
UM2581
USB Type-C™ FS
UM2581
-
Rev 2
page 27/48