STMicroelectronics Nucleo Development Board for STM32 Microcontrollers NUCLEO-F103RB NUCLEO-F103RB Data Sheet

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All the other solder bridges present on the STM32 Nucleo board are used to configure 
several IOs and power supply pins for compatibility of features and pinout with STM32 MCU 
supported.

All STM32 Nucleo boards are delivered with the solder-bridges configured according to the 
target MCU supported. 

SB57 (VREF+)

ON

VREF+ on STM32 MCU is connected to VDD.

OFF

VREF+ on STM32 MCU is not connected to VDD and can be provided from pin 

7 of CN10

SB62, SB63 (USART)

ON

PA2 and PA3 on STM32 MCU are connected to D1 and D0 (pin 7 and pin 8) on 

Arduino connector CN9 and ST Morpho connector CN10 as USART signals. 

Thus SB13 and SB14 should be OFF.

OFF

PA2 and PA3 on STM32 MCU are disconnected to D1 and D0 (pin 7 and pin 8) 

on Arduino connector CN9 and ST Morpho connector CN10.

SB13, SB14 

(ST-LINK-USART) 

OFF

PA2 and PA3 on STM32F103CBT6 (ST-LINK MCU) are disconnected to PA3 

and PA2 on STM32 MCU.

ON

PA2 and PA3 on STM32F103CBT6 (ST-LINK MCU) are connected to PA3 and 

PA2 on STM32 MCU to have USART communication between them. Thus 

SB61,SB62 and SB63 should be OFF.

OFF

MCO on STM32F103CBT6 (ST-LINK MCU) are disconnected to PF0/PD0/PH0 

on STM32 MCU.

ON

MCO on STM32F103CBT6 (ST-LINK MCU) are connected to PF0/PD0/PH0 on 

STM32 MCU.

1. The default SBx state is shown in bold.
2. Default configuration depends on board version. Please refer to chapter 5.7.1 for details
3. Default configuration depends on board version. Please refer to chapter 5.7.2 for details.