[National Technology N32G457 Review] RT_Thread Studio transplants USB virtual serial port

lugl4313820

[National Technology N32G457 Review] RT_Thread Studio transplants USB virtual serial port [Copy link]

 

Using the built-in USB function of N32G45, connect the computer USB, virtualize a USB serial port, and realize data communication between the computer and the development board. The official MDK provides an example. Using RT_Thread Studio, it does not work after being configured as USB. Now port the MDK program in the example to rt_thread_studio.

1. Create a new usb_driver folder in packages, copy the Virtual_COM_Port folder in the example to this directory, and then copy the Nationstech.N32G45x_Library.1.1.1\firmware\n32g45x_usbfs_driver folder to the directory.

Add the compiled directory to the project directory:

Delete main.c and main.h under Vitrual_COM_Port

Then compile, there will be many errors, many of which are repeated definitions of functions in n32g45x_it.c, delete the repeated functions. Another is to add the n32g45x.h header file. After the compilation is successful, add the header file and USB initialization function in main.c of applications

#include <stdint.h>
#include <rtthread.h>
#include <rtdevice.h>
#include "hw_config.h"
#include "usb_lib.h"
#include "usb_pwr.h"

/* defined the LED1 pin: PB5 */
#define LED1_PIN    100

int main(void)
{
    uint32_t Speed = 200;
    /* set LED1 pin mode to output */
    rt_pin_mode(LED1_PIN, PIN_MODE_OUTPUT);
    USB_Interrupts_Config();
    Set_USBClock();
    USB_Init();
    while (1)
    {
        rt_pin_write(LED1_PIN, PIN_LOW);
        rt_thread_mdelay(Speed);
        rt_pin_write(LED1_PIN, PIN_HIGH);
        rt_thread_mdelay(Speed);
    }
}

After the compilation is successful, download it to the development board and restart it: The computer successfully detects the serial port:

Use the serial port assistant to connect to the virtual serial port and send data to the development board: The development board shell successfully prints out:

The USB virtual serial port receiving function is void EP3_OUT_Callback(void) in usb_endp.c. If data needs to be processed, it can be processed here.

/*******************************************************************************
* Function Name  : EP3_OUT_Callback
* Description    :
* Input          : None.
* Output         : None.
* Return         : None.
*******************************************************************************/
void EP3_OUT_Callback(void)
{
  uint16_t USB_Rx_Cnt;
  
  /* Get the received data buffer and update the counter */
  USB_Rx_Cnt = USB_SilRead(EP3_OUT, USB_Rx_Buffer);
  
  /* USB data will be immediately processed, this allow next USB traffic being 
  NAKed till the end of the USART Xfer */
  
  USB_To_USART_Send_Data(USB_Rx_Buffer, USB_Rx_Cnt);
 
  /* Enable the receive of data on EP3 */
  USB_SetEpRxValid(ENDP3);
}

The USB virtual serial port sending function is hw_config.c

/*******************************************************************************
* Function Name  : USB_To_USART_Send_Data.
* Description    : send the received data from USB to the UART 0.
* Input          : data_buffer: data address.
                   Nb_bytes: number of bytes to send.
* Return         : none.
*******************************************************************************/
void USB_To_USART_Send_Data(uint8_t* data_buffer, uint8_t Nb_bytes)
{
  
  uint32_t i;
  
  for (i = 0; i < Nb_bytes; i++)
  {
    USART_SendData(USART1, *(data_buffer + i));
    while(USART_GetFlagStatus(USART1, USART_FLAG_TXDE) == RESET); 
  }  
}

You can modify it as needed, use the usb_ virtual serial port, save a USB-TTL is also very convenient. The project upload is as follows:

wangerxian

Test what happens when sending data larger than 64 bytes.

lugl4313820

Indicates no pressure:

lugl4313820

I wanted to write it in the same way as stm32 as device registration, but I couldn't find any information.

wangerxian

means no pressure:

Did he split it into 64-byte packets?

lugl4313820

wangerxian posted on 2022-2-9 22:06 Did he split it into 64-byte packets?

I specifically looked up the USB interface buf and found that the longest packet received is 64.

lugl4313820

/* Private variables ---------------------------------------------------------*/
uint8_t USB_Rx_Buffer[VIRTUAL_COM_PORT_DATA_SIZE];

#define VIRTUAL_COM_PORT_DATA_SIZE 64

Maybe it’s because of the DEMO, so it directly transfers to rt_printf, so there is no problem.