在FreeRTOS上运行的MicroROS，适用于任何STM32平台

文章目录

前言

`本文主要分享一下如何快速在stm32f103或stm32系列的任意板子上运行microros的具体步骤。（所需要的文件已经生成好了）。
生成的步骤极其踩坑，是一段令人痛苦的回忆。
生成静态链接库的踩坑主要内容就是 所有资源都是外网，需要代理，如果网络不通畅所有的步骤都得重新来，尤其是在docker 容器运行时的代理配置，直接给我干吐血了…
好的废话不多说，此篇文章的只需要下载工程后，即可使用（对于stm32f103rct6），其他芯片的可通过cubemx软件选择对应芯片即可。
对于microros如何从源码开始编译可点击以下链接

microros部署教程
microros github源码
microros 官网

一、工程下载

链接：https://pan.baidu.com/s/1QUw-3e9ZpeAaA7Khyjd_Dg?pwd=iebe
提取码：iebe
–来自百度网盘超级会员V4的分享

二、使用步骤

1.了解每个文件夹的作用

microros2pc_test 用于开发板与linux端ros2通信测试功能包
microros_ws 构建静态链接库，agent等功能包的setup功能包 具体使用可参考microros官网
microros_agent_ws linux端运行microros的agent功能包
freertos_rosnode stm32工程文件，包含了静态链接 .a文件
在freertos_rosnode下的micro_ros_stm32cubemx_utils文件夹是极其重要的文件夹，一般不做修改，移植所需文件夹 。同时可参考其中的main.c文件如何编程microros

2.移植到自己的工程

打开stm32 cubemx，创建一个新的工程 （我以stm32f103rct6为例）

1.正常配置时钟树即可

2.rcc配置 HSE选择crystal

选择中间件 middleware，选择freertos。如下配置 选择v2版本 选择tasks and queues双击已存在的tasks
配置 stack size 3000 allocation static

3.配置usart：
mode 选择asynchronous
dma settings 点击add
rx mode选择circular
tx默认即可
两者优先级都为非常高
nvic settings 打开中断
配置图如下

4.sys配置
打开debug
timebase source 选择tim1

5.工程管理：
toolchan/ide 选择makefile

6.代码生成：

生成代码 打开工程所在位置，将百度网盘下载的工程中的micro_ros_stm32cubemx_utils文件夹复制到新生成的工程文件夹目录下
如图所示

使用你最常用的ide或者编辑器打开工程（我以clion为例，配置文件可复制.idea文件夹到新工程目录下）：需要配置好工具链，如果没有配置，可参考稚晖君配置教程（clion）
编辑makefile文件：
将以下内容复制到 build the application之前

#######################################
# micro-ROS addons
#######################################
LDFLAGS += micro_ros_stm32cubemx_utils/microros_static_library/libmicroros/libmicroros.a
C_INCLUDES += -Imicro_ros_stm32cubemx_utils/microros_static_library/libmicroros/microros_include

# Add micro-ROS utils
C_SOURCES += micro_ros_stm32cubemx_utils/extra_sources/custom_memory_manager.c
C_SOURCES += micro_ros_stm32cubemx_utils/extra_sources/microros_allocators.c
C_SOURCES += micro_ros_stm32cubemx_utils/extra_sources/microros_time.c

# Set here the custom transport implementation
C_SOURCES += micro_ros_stm32cubemx_utils/extra_sources/microros_transports/dma_transport.c

print_cflags:
   @echo $(CFLAGS)

最好按照cubemx语法规则放入注释之间，这样在cubemx软件新添配置后代码不会被覆盖

/* USER CODE BEGIN PM */

/* USER CODE END PM */

将以下头文件复制到freertos.c文件中

#include "usart.h"
#include <rcl/rcl.h>
#include <rcl/error_handling.h>
#include <rclc/rclc.h>
#include <rclc/executor.h>
#include <uxr/client/transport.h>
#include <rmw_microxrcedds_c/config.h>
#include <rmw_microros/rmw_microros.h>
#include <std_msgs/msg/int32.h>

bool cubemx_transport_open(struct uxrCustomTransport * transport);
bool cubemx_transport_close(struct uxrCustomTransport * transport);
size_t cubemx_transport_write(struct uxrCustomTransport* transport, const uint8_t * buf, size_t len, uint8_t * err);
size_t cubemx_transport_read(struct uxrCustomTransport* transport, uint8_t* buf, size_t len, int timeout, uint8_t* err);

void * microros_allocate(size_t size, void * state);
void microros_deallocate(void * pointer, void * state);
void * microros_reallocate(void * pointer, size_t size, void * state);
void * microros_zero_allocate(size_t number_of_elements, size_t size_of_element, void * state);

再将StartDefaultTask（）函数中的内容替换为以下内容

void StartDefaultTask(void *argument)
{
    /* USER CODE BEGIN StartDefaultTask */
    /* Infinite loop */
    // micro-ROS configuration

    rmw_uros_set_custom_transport(
      true,
      (void *) &huart1,
      cubemx_transport_open,
      cubemx_transport_close,
      cubemx_transport_write,
      cubemx_transport_read);

    rcl_allocator_t freeRTOS_allocator = rcutils_get_zero_initialized_allocator();
    freeRTOS_allocator.allocate = microros_allocate;
    freeRTOS_allocator.deallocate = microros_deallocate;
    freeRTOS_allocator.reallocate = microros_reallocate;
    freeRTOS_allocator.zero_allocate =  microros_zero_allocate;

    if (!rcutils_set_default_allocator(&freeRTOS_allocator)) {
        printf("Error on default allocators (line %d)\n", __LINE__);
    }

    // micro-ROS app

    rcl_publisher_t publisher;
    std_msgs__msg__Int32 msg;
    rclc_support_t support;
    rcl_allocator_t allocator;
    rcl_node_t node;

    allocator = rcl_get_default_allocator();

    //create init_options
    rclc_support_init(&support, 0, NULL, &allocator);

    // create node
    rclc_node_init_default(&node, "cubemx_node", "", &support);

    // create publisher
    rclc_publisher_init_default(
      &publisher,
      &node,
      ROSIDL_GET_MSG_TYPE_SUPPORT(std_msgs, msg, Int32),
      "cubemx_publisher");

    msg.data = 0;

    for(;;)
    {
      rcl_ret_t ret = rcl_publish(&publisher, &msg, NULL);
      if (ret != RCL_RET_OK)
      {
        printf("Error publishing (line %d)\n", __LINE__);
      }

      msg.data++;
      osDelay(10);
    }
    /* USER CODE END StartDefaultTask */
}

添加syscalls.c：
在工程目录的core/src目录下新建syscalls.c文件，并复制以下内容到新建文件中

/**
*****************************************************************************
**
**  File        : syscalls.c
**
**  Author        : Auto-generated by System workbench for STM32
**
**  Abstract    : System Workbench Minimal System calls file
**
**                   For more information about which c-functions
**                need which of these lowlevel functions
**                please consult the Newlib libc-manual
**
**  Target      : STMicroelectronics STM32
**
**  Distribution: The file is distributed “as is,” without any warranty
**                of any kind.
**
*****************************************************************************
** @attention
**
** <h2><center>&copy; COPYRIGHT(c) 2019 STMicroelectronics</center></h2>
**
** Redistribution and use in source and binary forms, with or without modification,
** are permitted provided that the following conditions are met:
**   1. Redistributions of source code must retain the above copyright notice,
**      this list of conditions and the following disclaimer.
**   2. Redistributions in binary form must reproduce the above copyright notice,
**      this list of conditions and the following disclaimer in the documentation
**      and/or other materials provided with the distribution.
**   3. Neither the name of STMicroelectronics nor the names of its contributors
**      may be used to endorse or promote products derived from this software
**      without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
** DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
** OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**
*****************************************************************************
*/

// the code was modified by Fynn Boyer

/* Includes */
#include <sys/stat.h>
#include <stdlib.h>
#include <errno.h>
#include <stdio.h>
#include <signal.h>
#include <time.h>
#include <sys/time.h>
#include <sys/times.h>


/* Variables */
//#undef errno
extern int errno;
extern int __io_putchar(int ch) __attribute__((weak));
extern int __io_getchar(void) __attribute__((weak));

register char * stack_ptr asm("sp");

char *__env[1] = { 0 };
char **environ = __env;

extern char _estack;  // see ld file
extern char _Min_Stack_Size;  // see ld file

/* Functions */
void initialise_monitor_handles()
{
}

int _getpid(void)
{
    return 1;
}

int _kill(int pid, int sig)
{
    errno = EINVAL;
    return -1;
}

void _exit (int status)
{
    _kill(status, -1);
    while (1) {}        /* Make sure we hang here */
}

__attribute__((weak)) int _read(int file, char *ptr, int len)
{
    int DataIdx;

    for (DataIdx = 0; DataIdx < len; DataIdx++)
    {
        *ptr++ = __io_getchar();
    }

    return len;
}

__attribute__((weak)) int _write(int file, char *ptr, int len)
{
    int DataIdx;

    for (DataIdx = 0; DataIdx < len; DataIdx++)
    {
        __io_putchar(*ptr++);
    }
    return len;
}

caddr_t _sbrk(int incr) {
    extern char __heap_start__ asm("end");  // Defined by the linker.
    static char *heap_end;
    char *prev_heap_end;

    if (heap_end == NULL) heap_end = &__heap_start__;

    prev_heap_end = heap_end;

    if (heap_end + incr > &_estack - _Min_Stack_Size) {
        __asm("BKPT #0\n");
        errno = ENOMEM;
        return (caddr_t)-1;

    }

    heap_end += incr;
    return (caddr_t)prev_heap_end;

}

int _close(int file)
{
    return -1;
}


int _fstat(int file, struct stat *st)
{
    st->st_mode = S_IFCHR;
    return 0;
}

int _isatty(int file)
{
    return 1;
}

int _lseek(int file, int ptr, int dir)
{
    return 0;
}

int _open(char *path, int flags, ...)
{
    /* Pretend like we always fail */
    return -1;
}

int _wait(int *status)
{
    errno = ECHILD;
    return -1;
}

int _unlink(char *name)
{
    errno = ENOENT;
    return -1;
}

int _times(struct tms *buf)
{
    return -1;
}

int _stat(char *file, struct stat *st)
{
    st->st_mode = S_IFCHR;
    return 0;
}

int _link(char *old, char *new)
{
    errno = EMLINK;
    return -1;
}

int _fork(void)
{
    errno = EAGAIN;
    return -1;
}

int _execve(char *name, char **argv, char **env)
{
    errno = ENOMEM;
    return -1;
}

再编辑makefile文件，加入syscalls.c文件路径
在
######################################
source
######################################
C sources
下加入

Core/Src/syscalls.c \

最后编译即可

最后下载固件到开发板上即可。

3.运行！

1.将agent功能包上传到linux中（linux需安装ros2系统，版本为foxy）
2.最好编译一下，source功能包后运行以下命令

ros2 run micro_ros_agent micro_ros_agent serial -b 115200 --dev /dev/ttyUSB0

其中ttyUSB0要根据开发板连接的代号来修改
注意 一定要先运行上述命令后再连接开发板
效果如下

出现以下情况后连接开发板，会出现以下情况

说明开发板与ros2连接成功
再运行`

ros2 topic echo /cubemx_publisher

可查看microros发布的信息
如图

运行以下命令 可查看节点信息

rqt_graph

说明stm32f103的节点已启动！

作者：唯亦@