0
点赞
收藏
分享

微信扫一扫

USB协议学习笔记 - 虚拟串口Virtual Port Com LED控制

素锦时年_1b00 2022-02-20 阅读 86
#define#include串口智能硬件嵌入式

前言

  • STM32 的USB 可以虚拟成一个串口，功能还挺强，感觉比HID好用
  • 这里使用USB 虚拟的串口，做个控制LED的小程序
  • 控制LED这里使用自定义的AT命令方式，如红灯亮：AT+LEDR_ON，红灯灭：AT+LEDR_OFF

程序如下

  • 首先STM32 USB虚拟成串口的操作，参考前面的文章
  • LED.c 
    
#include "led.h"

/ all LEDS gpio init /
void leds_gpio_init(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};

LEDR_GPIO_RCC_ENABLE();
LEDG_GPIO_RCC_ENABLE();
LEDB_GPIO_RCC_ENABLE();

HAL_GPIO_WritePin(LEDR_GPIO_PORT, LEDR_GPIO_PINS, GPIO_PIN_SET);
HAL_GPIO_WritePin(LEDG_GPIO_PORT, LEDG_GPIO_PINS, GPIO_PIN_SET);
HAL_GPIO_WritePin(LEDB_GPIO_PORT, LEDB_GPIO_PINS, GPIO_PIN_SET);

GPIO_InitStruct.Pin = LEDR_GPIO_PINS;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
HAL_GPIO_Init(LEDR_GPIO_PORT, &GPIO_InitStruct);

GPIO_InitStruct.Pin = LEDG_GPIO_PINS;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
HAL_GPIO_Init(LEDG_GPIO_PORT, &GPIO_InitStruct);

GPIO_InitStruct.Pin = LEDB_GPIO_PINS;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
HAL_GPIO_Init(LEDB_GPIO_PORT, &GPIO_InitStruct);

}

/ LEDR power control /
void LEDR_power_ctrl(unsigned int bon)
{
if (bon == 0x01) / LEDR ON /
{
HAL_GPIO_WritePin(LEDR_GPIO_PORT, LEDR_GPIO_PINS, GPIO_PIN_RESET);
}
else
{
HAL_GPIO_WritePin(LEDR_GPIO_PORT, LEDR_GPIO_PINS, GPIO_PIN_SET);
}
}

/ LEDG power control /
void LEDG_power_ctrl(unsigned int bon)
{
if (bon == 0x01) / LEDG ON /
{
HAL_GPIO_WritePin(LEDG_GPIO_PORT, LEDG_GPIO_PINS, GPIO_PIN_RESET);
}
else
{
HAL_GPIO_WritePin(LEDG_GPIO_PORT, LEDG_GPIO_PINS, GPIO_PIN_SET);
}
}

/ LEDB power control /
void LEDB_power_ctrl(unsigned int bon)
{
if (bon == 0x01)
{
HAL_GPIO_WritePin(LEDB_GPIO_PORT, LEDB_GPIO_PINS, GPIO_PIN_RESET);
}
else
{
HAL_GPIO_WritePin(LEDB_GPIO_PORT, LEDB_GPIO_PINS, GPIO_PIN_SET);
}
}

- `led.h`
```c
#ifndef __LED_H__
#define __LED_H__

#include "stm32l4xx_hal.h"

#define LEDR_GPIO_RCC_ENABLE()  __HAL_RCC_GPIOE_CLK_ENABLE()
#define LEDR_GPIO_PORT          GPIOE
#define LEDR_GPIO_PINS          GPIO_PIN_7

#define LEDG_GPIO_RCC_ENABLE()  __HAL_RCC_GPIOE_CLK_ENABLE()
#define LEDG_GPIO_PORT          GPIOE
#define LEDG_GPIO_PINS          GPIO_PIN_8

#define LEDB_GPIO_RCC_ENABLE()  __HAL_RCC_GPIOE_CLK_ENABLE()
#define LEDB_GPIO_PORT          GPIOE
#define LEDB_GPIO_PINS          GPIO_PIN_9

void leds_gpio_init(void);
void LEDG_power_ctrl(unsigned int bon);
void LEDR_power_ctrl(unsigned int bon);
void LEDB_power_ctrl(unsigned int bon);

#endif
  • 这里修改usbd_cdc_if.c 中的串口数据接收函数：CDC_Receive_FS 
    
extern void ata_buff_put(uint8_t *buf);
/**
* @brief  Data received over USB OUT endpoint are sent over CDC interface
*         through this function.
*
*         @note
*         This function will issue a NAK packet on any OUT packet received on
*         USB endpoint until exiting this function. If you exit this function
*         before transfer is complete on CDC interface (ie. using DMA controller)
*         it will result in receiving more data while previous ones are still
*         not sent.
*
* @param  Buf: Buffer of data to be received
* @param  Len: Number of data received (in bytes)
* @retval Result of the operation: USBD_OK if all operations are OK else USBD_FAIL
*/

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);

ata_buff_put(UserRxBufferFS); /* recv user command */
return (USBD_OK);
/* USER CODE END 6 */

}

- `main.c`
```c
#include "main.h"
#include "usb_device.h"
#include "usbd_cdc_if.h"
#include <stdio.h>
#include <stdarg.h>
#include "led.h"

void SystemClock_Config(void);
static void MX_GPIO_Init(void);

#define ENABLE_ATA_TEST
#define DBG_BUFF_MAX_LEN          256
#define ATA_BUFF_MAX_LEN          256

static uint8_t ata_buf[ATA_BUFF_MAX_LEN] = { 0 };
static uint8_t ata_recv_flag = 0x00;

void ata_buff_put(uint8_t *buf)
{
    if (buf == 0)
        return;
    strncpy((char *)ata_buf, (const char *)buf, ATA_BUFF_MAX_LEN);
    ata_recv_flag = 0x01;
}

void usb_vcom_puts(uint8_t *buf)
{
    CDC_Transmit_FS(buf, strlen((const char *)buf));
}

/* debug print : support float double */
int printk(const char *fmt, ...)
{
    va_list args;
    static char log_buf[DBG_BUFF_MAX_LEN] = { 0 };

    va_start(args, fmt);
    int length = vsnprintf(log_buf, sizeof(log_buf) - 1, fmt, args);

    usb_vcom_puts((uint8_t *)log_buf);

    return length;
}

void ata_notify_handler(void)
{
#ifdef ENABLE_ATA_TEST
    if (ata_recv_flag == 0)
        return;

    uint8_t sendbuffer[ATA_BUFF_MAX_LEN];

    if (strlen((char *)ata_buf) <= 5) /* AT+XX\r\n */
        return;

    memset(sendbuffer,0,sizeof(sendbuffer));

    if(strncmp((char *)ata_buf,"AT+LEDR_ON",strlen("AT+LEDR_ON"))==0) /* LEDR ON */
    {
        LEDR_power_ctrl(1);
        printk("OK\r\n");
    }
    else if(strncmp((char *)ata_buf,"AT+LEDR_OFF",strlen("AT+LEDR_OFF"))==0) /* LEDR OFF */
    {
        LEDR_power_ctrl(0);
        printk("OK\r\n");
    }
    else if(strncmp((char *)ata_buf,"AT+LEDG_ON",strlen("AT+LEDG_ON"))==0) /* LEDG ON */
    {
        LEDG_power_ctrl(1);
        printk("OK\r\n");
    }
    else if(strncmp((char *)ata_buf,"AT+LEDG_OFF",strlen("AT+LEDG_OFF"))==0) /* LEDG OFF */
    {
        LEDG_power_ctrl(0);
        printk("OK\r\n");
    }
    else if(strncmp((char *)ata_buf,"AT+LEDB_ON",strlen("AT+LEDB_ON"))==0) /* LEDB ON */
    {
        LEDB_power_ctrl(1);
        printk("OK\r\n");
    }
    else if(strncmp((char *)ata_buf,"AT+LEDB_OFF",strlen("AT+LEDB_OFF"))==0) /* LEDB OFF */
    {
        LEDB_power_ctrl(0);
        printk("OK\r\n");
    }
    else
    {
        printk("NO CMD found! %s\r\n", ata_buf);
    }
    ata_recv_flag = 0x00;
#endif
}

int main(void)
{
    uint32_t cnt = 0x00;
    HAL_Init();
    SystemClock_Config();
    MX_GPIO_Init();
    leds_gpio_init();
    MX_USB_DEVICE_Init();

    HAL_Delay(2000);
    printk("%s : STM32 USB Virtual Port Com LED Test!\r\n", __func__, cnt);
    while (1)
    {
        ata_notify_handler();
    }
}

烧写验证

  • 编译下载后，电脑端打开串口助手，并打开STM32虚拟的USB串口
  • 尝试在串口助手发送：AT+LEDG_OFF AT+LEDG_ON 等LED指令（注意追加回车换行），发现LED可以正常的控制亮灭

在这里插入图片描述

小结

  • USB 虚拟串口，功能还是挺使用的，可以用于普通的串口的输入与输出，可以用于通信与控制，比USB HID要简单一些
  • 继续研究USB的应用（使用），并不断的整理USB相关的资料，深入学习USB协议与应用技术
举报

相关推荐

USB协议学习笔记 - CDC类虚拟串口Virtual Port Com

串口数据插入图片智能硬件嵌入式

USB协议学习笔记 - 虚拟串口Virtual Port Com用于LOG打印

#include串口虚拟串口智能硬件嵌入式

USB协议学习笔记 - CUSTOM HID控制LED

#define数据插入图片智能硬件嵌入式

USB协议学习笔记

上位机插入图片数据传输智能硬件嵌入式

串口printf和USB虚拟串口printf

串口虚拟串口电路设计Linux系统/运维

USB协议学习笔记 - 引言

stm32USB上位机Data固件Html/CSS前端开发

USB协议学习笔记 - HID 设备

USBHID智能硬件嵌入式

STM32 USB CDC 虚拟串口

jmeter自动化测试软件测试功能测试程序人生职场发展

USB协议学习笔记 - CUSTOM HID 设备

插入图片#include鼠标坐标驱动/内核开发嵌入式

AndroidThings学习笔记--pwm控制Led闪烁

androidListideHtml/CSS前端开发
0 条评论