Peripheral in conflicts with others

[SMusc.1]

Hello everyone, I have the following question: when, as in the attached image, you see a peripheral like the USART1 in yellow (in conflict with other peripherals), is it still possible to use it? I ask this information because I am looking for a NUCLEO card that best meets my specifications and I want to avoid buying a card for which I can not use the peripherals I need to the fullest.

[mƎALLEm]

From the schematic of the board:

You can use the USART1 in Asynchronous mode, so no conflicts with USB. I didn't check the pinouts but I suppose the conflicts resides in the USART synchronous mode and USB when used at the same time.

With that Nucleo board you can use USART1 with STLINK-Virtual comport where you can use it directly with HyperTerminal.

If you need to use USART1 externally you need to remove SB32 and SB34 solder bridges to remove the conflict with the STLINK.

Hope I answered your question.

[SMusc.1]

Hi, I am trying to find out if a card: F207ZGT is right for me. For this reason I have selected the peripherals I need. If I go to USART1 I see that it is the conflict with the USB, partially in asynchronous mode and totally in synchronous mode. My questions are the following:
1) by disabling the USB peripherals on the pins that are set to default, what can I run into? Can you provide some examples of applications that use the USB peripheral PINs?
2) if I leave the USB peripherals active and continue to use the USART1 in asynchronous mode (therefore partially), will I be able to establish communication with a serial terminal for example without problems or not at all?

Attached the screen shot of the board that I am interested in purchasing and that i am talking above regarding the USART1 conflict.

[mƎALLEm]

Sorry I didn't understand, you previously talked about NUCLEO-U575ZI now you are talking about F207!

Please stick on one MCU/board..

[Ozone]

Looking it up quickly, the F207ZGT has two options for the USART1 pins : PA9 + PA10, and PB6 + PB7.

> 2) if I leave the USB peripherals active and continue to use the USART1 in asynchronous mode (therefore partially), will I be able to establish communication with a serial terminal for example without problems or not at all?

I always used asynchronous UARTs for communication to external terminals, and never experienced problems.

[SMusc.1]

 F207!

[Andrew Neil]

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@SMusc.1 wrote:

2) if I leave the USB peripherals active and continue to use the USART1 in asynchronous mode (therefore partially), will I be able to establish communication with a serial terminal for example without problems or not at all?

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Of course - provided it's an asynchronous serial terminal.

Not that I've ever seen a synchronous serial terminal ...

[Andrew Neil · Accepted solution]

With any interface on any board, you need to check that things on that board won't interfere with what you intend to do.

Common things which could interfere:

• Switches (buttons)
• LEDs
• ST-Link VCOM (Virtual COM port)
• USB 
• Ethernet
• Displays
• etc, etc, ...

The way to check is in the board's User Manual and the Schematics - which can be found on the Product Page

The attraction of Nucleo boards is that they tend to have minimal "extras" - so you get maximum choice of what pins are free to use.

But, rather than just saying "I want to use USART1", a better approach may be to say "I want to use a USART" - and then look for which USART(s) is/are free ...

This is not specific to STM32 or even ST - the same arises with any microcontroller

[Andrew Neil]

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@Andrew Neil wrote:

rather than just saying "I want to use USART1"

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Do you even need a USART at all?

If your application only requires UART (no 'S') - then just say, "UART"