Clock Source; Reset Sources; Usb Device Fs; Quad-Spi Nor Flash Memory - STMicroelectronics B-L462E-CELL1 User Manual

7.3

Clock source

One clock source is described below:
• X1 8 MHz clock for the ST-LINK MCU.
The other clock source is the 32.768 KHz in the module which is used to be the RTC clock source for the
STM32L462RE microcontroller.
7.4

Reset sources

The reset signal of the B-L462E-CELL1 Discovery kit for IoT nodes is active LOW and the reset sources include:
• A reset button B1
• An embedded ST-LINK/V2-1
• A TAG10 connector reset pad
7.5

USB device FS

The B-L462E-CELL1 Discovery kit for IoT nodes supports USB device function via the CN8 USB Micro-B
connector.
7.6

Quad-SPI NOR Flash memory

64 Mbytes of onboard Quad-SPI Flash memory (MT25QU512ABB1EW9-0SIT from Micron) is connected to the
Quad-SPI interface of STM32L462RE in LBAD0ZZ1SE. The Flash shares the same QSPI IO as on‑module Flash
memory. So solder bridge is used to select the target Flash memory (SB43 is OFF and SB28 is ON). On‑module
Flash is used by default.
7.7

Virtual COM port

The serial interface USART1 is directly available as a Virtual COM port of the PC connected to the CN9 ST-LINK/
V2-1 USB connector. The Virtual COM port settings are configured with 115200 bps, 8‑bit data, no parity, one stop
bit, and no flow control.
7.8

STMicroelectronics sensors

Several STMicroelectronics sensors are available on the B-L462E-CELL1 Discovery kit for IoT nodes and are
listed below:
•

Ultra-low-power 3D accelerometer and 3D magnetometer (LSM303AGR)

• 260 hPa to 1260 hPa absolute digital output barometer (LPS22HH)
• Capacitive digital sensor for relative humidity and temperature (HTS221)
7.8.1 Ultra-low-power 3D accelerometer and 3D magnetometer (LSM303AGR)
LSM303AGR is an ultra-low-power high-performance system-in-package featuring a 3D digital linear acceleration
sensor and a 3D digital magnetic sensor.
LSM303AGR has linear acceleration full scales of ±2g/±4g/±8g/16g and a magnetic field dynamic range of
±50 gauss.
LSM303AGR includes an I
speed (100 kHz, 400 kHz, 1 MHz, and 3.4 MHz) and an SPI serial standard interface. On the B-L462E-CELL1
Discovery kit for IoT node the I2C1 bus from the STM32L462REY6TR is used.
The system can be configured to generate an interrupt signal for free-fall, motion detection, and magnetic field
detection.
The magnetic and accelerometer blocks can be enabled or put into power-down mode separately.
LSM303AGR is available in a plastic land grid array package (LGA) and is guaranteed to operate over an
extended temperature range from -40 °C to +85 °C.
• 3 magnetic field channels and 3 acceleration channels
UM2743 - Rev 1
2
C serial bus interface that supports standard, fast mode, fast mode plus, and high-
UM2743
Clock source
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