Powering NUCLEO-H743ZI2 with User USB?

[JJ.5]

I'm currently working on a project involving a NUCLEO-H743ZI2 board.

I want to know if it's possible to power the board with User USB instead of ST-Link USB.

Or if it's possible to transfer data using ST-Link USB and use User USB for debugging.

Thank you in advance!

[Nikita91]

Have a look at the board schematics page 7: https://www.st.com/resource/en/schematic_pack/mb1364-h743zi-c01_schematic.pdf

There is no way to connect the VBUS from the user USB connector to the board power supply.

You can use the ST-LINK USB to transfer data using the VCP port (connected MCU USART3), not using USB protocol.

I don't thing you can use user USB to debug with ST-LINK...

[FLeon.4]

Yes, it is possible to power the NUCLEO-H743ZI2 board using the User USB instead of the ST-Link USB. You can connect the board to a power source through the User USB port. As for data transfer and debugging, you can use the ST-Link USB for both purposes simultaneously. This allows you to transfer data between the board and your computer while using the User USB for debugging operations.

[Rodo]

"Yes, it is possible to power the NUCLEO-H743ZI2 board using the User USB instead of the ST-Link USB" This statement does not agree with the schematic pointed out by Nikita91.

[S.Ma]

My understanding:

NUCLEO boards have 1 USB port for debugging (STLinkV2/3) the target MCU.

This can be the power source of the target MCU. If legacy micro-USB, the budget will be 500mA minus the debugger (if V3, 100-150mA left).

Most STLinks have built-in USB to Serial (UART) translators, connected to specific RX/TX of target MCU. You can use it if you implement code in the target MCU (to make printf, console, etc.... as you wish)

Now the target USB (the port connected to the target MCU USB-Pins) can power the target chip.

If plugged to a PC (and not a power bank), if the target MCU doesn't have USB SW, non-USB-C plugs will provide 100mA. With target USB SW, you can declare to be a high powered device (500mA).

Another way to provide power is through Arduino Vin source which goes to a 5V built-in regulator.

There should be jumpers to select the power source for the target.

With USB-C, max current ratings may be pushed up.

[Rodo]

"Now the target USB (the port connected to the target MCU USB-Pins) can power the target chip." This statement does not agree with the schematic pointed out by Nikita91.

[Pavel A.]

See UM2407 6.4.3: there is option for external 5V and 3.3V power. If you connect the ext. 5V supply pin to the USB power wire ...

[JJ.5]

I'm not sure it's safe to jump wire between USB power and Ext. 5v.

I can give a try.

Thank you for the information.

[Nikita91]

Yes JP2 allows to select among various 5V power inputs, but not from the user USB...

As @Pavel A.​  say you can solder a wire on the board!

[JJ.5]

Thanks for the replay.

Do you mean I should jump wire from VBUS to 5V power input?

Is it safe to do?

[Pavel A.]

Frankly I've never tried this)) A common ground is needed. But there's the 5V power.

[JJ.5]

@pavel A.​ @Nikita91​ @FLeon.4​ @Rodo​ 

I found the board NUCLEO-H743ZI2 can be powered by the user usb automatically.

First, I need to connect both ST-Link USB and User USB to two USB ports.

Then, I can just unplug the ST-Link USB and the board is still running.

Not sure why.

I also attached a image below. As you can see, the LED lights are on and ST-Link usb(black) is unplugged

 

The trick is let ST-Link USB power the board first then switch to User USB by unpluging the ST-Link USB.

I'm not sure this functionality is mentioned on the user manual.

Is there a way to make the board boot up from User USB?

Thanks!

[Pavel A.]

> Is there a way to make the board boot up from User USB?

Now we are back to square one.

[JJ.5]

Hello again,

What do you mean by "square one"?