VCP for STM32F3

[Erenburg.Evgeny]

Posted on February 21, 2018 at 14:09

I'm trying to implement Virtual Com Port on STM32F3. I use IAR.

I've included all files from a demo project.

However I have numerous errors while compiling the project. Struggling for hours I came to this question

Is there any compiled project with VCP for STM32F3?

Note: this post was migrated and contained many threaded conversations, some content may be missing.

[Bogdan Golab]

Posted on February 21, 2018 at 14:55

Discovery board? What model? Some come in two flavors - with and w/o VCOM supported. It's a matter of st-link version (2-1 and 2B support VCOM). See the documentation of the particular board

[Erenburg.Evgeny]

Posted on February 21, 2018 at 14:58

Can you advice what board come with VCP? I didn't find any.

I need it as a demo project for a user connectivity, not to program/debug with ST-LINK.

[henry.dick]

Posted on February 21, 2018 at 15:08

The list of boards with vcp is practically limitless, most of them of no use to you.

So you can help others help you by narrowing that down a little.

[Andrew Neil]

Posted on February 21, 2018 at 15:14

I have numerous errors while compiling the project

You're referring to this:

https://community.st.com/0D50X00009XkfBRSAZ

?

As noted there, you probably just have one actualmistake - but that results in a whole load of similar error reports.

This is quite common - one mistake causes resultant errors in everything else that depends upon it.

[Erenburg.Evgeny]

Posted on February 21, 2018 at 15:18

Well - I invented a shortcut - to take an example and to see what's going wrong.

[Erenburg.Evgeny]

Posted on February 22, 2018 at 07:33

I think I have to clarify things. I want to connect my PC's USB to USB on a board  and use it as UART terminal.

[Bogdan Golab]

Posted on February 22, 2018 at 07:50

So select the Discovery or Nucleo model:

http://www.st.com/en/evaluation-tools/stm32-mcu-nucleo.html?querycriteria=productId=LN1847

 

http://www.st.com/en/evaluation-tools/stm32-mcu-discovery-kits.html?querycriteria=productId=LN1848

 

Look at price, sensors, displays, arduino connectors (can add extra HW  - arduino shields). All new boards supports VCP - Virtual COM emulated by the ST-LINK programmer / debugger.

Also boards equipped with the second USB port (Some if not all Discovery boards)  can use USB CDC  - direct connection from the MCU to the PC without ST-LINK.

[Erenburg.Evgeny]

Posted on February 22, 2018 at 08:55

Hi Bogdan,

I perfectly understand that all boards supports VCP. I have no problem with the hardware. The problem I didn't found any compiled VCP  example.

My English too bad? It's hard to understand what I want? I start to panic.

[Andrew Neil]

Posted on February 22, 2018 at 10:17

Perhaps this helps to distinguish the USB connection via the on-board ST-Link from the Target microcontroller's USB connection:

[Andrew Neil]

Posted on February 22, 2018 at 11:11

https://community.st.com/0D50X00009XkeivSAB

Specifically, this post:

https://community.st.com/0D50X00009XkeivSAB#comment-155054

[Erenburg.Evgeny]

Posted on February 22, 2018 at 11:45

MY DEAR LORD!!!

IS THERE ANY ADEQUATE PERSON ON THE FORUM UNDERSTANDING ME???

[Andrew Neil]

Posted on February 22, 2018 at 11:47

You seem to be the one failing to understand.

As has been explained a number of times, there are two possible ways to have a 'VCP' on a Nucleo or Discovery board. 

You have not yet clarified which particular 'VCP' option you require.

So, please answer the simple question: Is using the VCP provided by the ST-Link sufficient for you?

[Erenburg.Evgeny]

Posted on February 22, 2018 at 12:01

Provided by the ST-LINK??? How ST-LINK involved here?

I have STM32F3DISCOVERY BOARD (MB1035B)

I debug/program on USB-LINK connector. And VCP communication I what to run on USB USER connector.

A piece of the demo code

while ( 1 ) {

        if (bDeviceState == CONFIGURED)

        {

            STM_EVAL_LEDOn(LED6);

            CDC_Receive_DATA();

            /* Check to see if we have data yet */

            if (Receive_length  != 0)

            {

                STM_EVAL_LEDOn(LED4);

                int i;

                for (i = 0; i < Receive_length; i++) {

                    localBuffer[i] = Receive_Buffer[i];

                }

                CDC_Send_DATA(localBuffer, Receive_length);

                Receive_length = 0;

            }

        }

    }

The problem I can not compile the demo so I want to see compiled example for IAR.

Jesus Christ

! What I'm asking? NASA project?

[henry.dick]

Posted on February 22, 2018 at 17:25

It is not difficult to tell if your board supports vcp. Take a look at the schematic of your board. There should be a connection between the debuggers uart and the targets uart pins.

If there is, there is a chance you board supports vcp. Otherwise, no chance and you have to move on.

Later jtag support swo and jscope ... So that's another option.

[Andrew Neil]

Posted on February 22, 2018 at 17:50

dhenry wrote:

It is not difficult to tell if your board supports vcp.

I think you need to be clear that you're talking here about VCP via the ST-Link.

It's still not clear that the OP has understood that there are two possible ways to do 'VCP'; viz,

1. via the ST-Link;
2. by implementing USB/CDC on the target microcontroller.

[AvaTar]

Posted on February 22, 2018 at 18:29

Just to mention it - the F3 Discovery firmware package has an USB example project, too.

I guess it's not VCP specific code, though.

I think what the OP was trying to tell us as well - his F3 discovery has no ST-Link with VCP (V2, like mine).

So option 1 drops out.

[Andrew Neil]

Posted on February 22, 2018 at 18:38

AvaTar wrote:

I think what the OP was trying to tell us as well - his F3 discovery has no ST-Link with VCP (V2, like mine).

So option 1 drops out.

But I think that this thread, and the previous thread, demonstrate that it would be far simpler to just get a board with the VCP-equipped ST-Link ?

See:

https://community.st.com/0D50X00009XkfBTSAZ

The cost of the time spent on this so far would have bought several dozen Nucleo and/or discovery boards - with premium delivery!!

[Bogdan Golab]

Posted on February 22, 2018 at 18:51

For hobbyist like me more fun is to develop the VCP w/o st-link.

You are (unfortunately) professionals and 'time is money' is your every day mantra:)

[Erenburg.Evgeny]

Posted on February 25, 2018 at 09:14

Why I love professionals? - they resolve problems in a second.

Go to ST -> download STM32_USB-FS-Device_Lib_V4.1.0 -> have a demo for F3 in IAR.

[Ivan Elkin]

Posted on March 01, 2018 at 09:48

Hi 

erenburg.evgeny.002

I've check the code on stm32F103RE, STM32F4DISCOVERY, STM32F417

I use the CubeMX. And I'm sorry for long letter...

I setup CDC project for USB FS, set heap=stack=0x2000

usbd_cdc_if.c:

/* USER CODE BEGIN INCLUDE */

#include 'Device.h'

/* USER CODE END INCLUDE */

...

/* USER CODE BEGIN PRIVATE_TYPES */

//EXCLUDE_THIS_BEGIN

#if 0

/* USER CODE END PRIVATE_TYPES */

...

/* USER CODE BEGIN PRIVATE_VARIABLES */

#endif

//EXCLUDE_THIS_END

/* USER CODE END PRIVATE_VARIABLES */

...

static int8_t CDC_Control_FS  (uint8_t cmd, uint8_t* pbuf, uint16_t length)

{

...

case CDC_SET_LINE_CODING:

SetLineCoding((const SLineCoding*) pbuf);

break;

case CDC_GET_LINE_CODING:

GetLineCoding((SLineCoding*) pbuf);

break;

...

}

static int8_t CDC_Receive_FS (uint8_t* Buf, uint32_t *Len)

{

/* USER CODE BEGIN 6 */

// USBD_CDC_SetRxBuffer(&hUsbDeviceFS, &Buf[0]);

// USBD_CDC_ReceivePacket(&hUsbDeviceFS);

SeveUsbIncomingMessage(*Len);

return (USBD_OK);

/* USER CODE END 6 */

}

Now I create 2 files: Device(c|cpp,h)

Device.h:

#ifdef __cplusplus

extern 'C' {

#endif

typedef struct LineCoding

{

uint32_t bitRate;

uint8_t stopBits;

uint8_t parityType;

uint8_t dataBits;

} SLineCoding;

#define APP_RX_DATA_SIZE 64

#define APP_TX_DATA_SIZE 64

typedef uint8_t TRxBuffer[APP_RX_DATA_SIZE];

typedef uint8_t TTxBuffer[APP_TX_DATA_SIZE];

extern uint8_t* UserRxBufferFS;

extern uint8_t* UserTxBufferFS;

void SeveUsbIncomingMessage(uint32_t msgSize);

void SetLineCoding(const SLineCoding *lc);

void GetLineCoding(SLineCoding *lc);

void HandleMessage(void);

Device.c(pp):

void SeveUsbIncomingMessage(uint32_t msgSize)

{

gsUsbMsgSize = msgSize;

}

void HandleMessage(void)

{

ShowAlive();

if(0 > gsUsbMsgSize) {

return;

}

//Do some useful here

USBD_CDC_ReceivePacket(&hUsbDeviceFS);

}

static SLineCoding 

gsLineCoding;

void SetLineCoding(const SLineCoding *lc)

{

memcpy(reinterpret_cast<void *> (&gsLineCoding), reinterpret_cast<const void *> (lc),sizeof(gsLineCoding));

}

void GetLineCoding(SLineCoding *lc)

{

memcpy(reinterpret_cast<void *> (lc), reinterpret_cast<void *> (&gsLineCoding), sizeof(gsLineCoding));

}

main.c:

#include 'Device.h'

...

int main(...)

{

...

while(1)

{

...

HandleMessage();

...

}

}