Board Functions; Leds; Push-Buttons; Rf Overview - ST STM32WL Series User Manual

6.4

Board functions

6.4.1

LEDs

User LED (LD1)
This blue LED is a user LED connected to STM32WL5MOC module I/O PB15. To light the LD1 LED, a HIGH logic
state must be written in the corresponding GPIO PB15.
User LED (LD2)
This green LED is a user LED connected to STM32WL5MOC module I/O PB9. To light the LD2 LED, a HIGH
logic state must be written in the corresponding GPIO PB9.
User LED (LD3)
This red LED is a user LED connected to STM32WL5MOC module I/O PB11. To light the LD3 LED, a HIGH logic
state must be written in the corresponding GPIO PB11.
5V_PWR LED (LD4)
This green LED indicates that the CEB MB1779 board is powered, and 5 V power is available at the input of the
3V3 regulator (U6) to provide the 3.3 V necessary to supply the STM32WL5MOC module.
6.4.2

Push-buttons

SW1 user button
This user button is connected to the STM32WL5MOC module I/O PA0.
SW2 reset button
This push-button is connected to NRST and is used to reset the STM32WL5MOC module.
6.4.3

RF overview

The CEB MB1779 board embeds an STM32WL5MOC module and DC switches to address with the same board
the three reception, High-power transmission, and Low-power transmission modes. The choice between the two
transmission modes can be done dynamically, thanks to two DC switches controlled by SW_RF (GPIO from the
STM32WL series MCU):
• The transmission high-output power amplifier (PA HP) is supplied from the PA regulator (REG PA) up to
3.1 V. For this, the REG PA must be supplied directly from VDDSMPS.
• The transmission default low-output power amplifier (PA LP) can be supplied from the PA regulator (REG
PA) up to 1.35 V. For this, the REG PA must be supplied from the regulated VFBSMPS supply at 1.55 V.
UM3127 - Rev 1
UM3127
Hardware layout and configuration
page 15/47