STM32 LD1 Blinks and LD3 remains red

[jonathanmeyer]

Hello guys,

I have Nucleo F072RB, when I first bought it, it works fine when I plug it to PC. But today, When I plugged USB cable, LD1 blinks in approximately 1 HZ and LD3 remains red. I have searched it on the internet but I couldn't find a solution. I know there is a problem with LD1 because it should be remain red too.

If you help me, I will appreciate it.

[Imen.D]

Hello @Tuğrahan Karakadıoğlu​ and welcome to the Community 🙂

Check the jumper position on the board.

Is the jumper JP1 ON or OFF? JP1 should be OFF.

Did you connect the external power to the PIN 6 of CN7.

If you use VIN (Pin 24 of CN7 or Pin 8 of CN6)

The external power sources VIN and E5V are summarized in Table 7 in the UM1724.

When the board is power supplied by VIN or E5V, the jumpers configuration must be the following:

• Jumper on JP5 pin 2 and pin 3

• Jumper removed on JP1

If the host is not able to provide the required current, the targeted STM32 microcontroller and the MCU part including the extension board are not power supplied. As a consequence, the red LED LD3 remains turned OFF. In such a case it is mandatory to use an external power supply as explained in the next Section 6.3.2: External power supply inputs: VIN and E5V.  -UM1724-

In case the board is powered by a USB charger, there is no USB enumeration, so the led LD3 remains set to OFF permanently and the target STM32 is not powered. In this specific case, the jumper JP1 needs to be set to ON, to allow target STM32 to be powered anyway.

When your question is answered, please close this topic by choosing Select as Best. This will help other users find that answer faster.

Imen

[srinath]

Hello,

           I am working the nucleo board ,similarly my led is blinking at 1 Hz , I want to use power bank through the USB connector for my power supply, My power bank output is 5v ,2A . In the user manual it was mentioned as if you not want to use usb enumeration put the jumper j1 as ON , and also mentioned to  take care that input  should not exceed 100 mA. 

                 In my case jumper j1 is off and jumper 5 is on the usb power supply. what happen when I give 2 A power supply to the board by putting  j1 as ON . Is there any other way to do it.