1. 修改.ld文件

在STM32F407ZGTx_FLASH.ld增加如下内容。

  /* Uninitialized data section */
  . = ALIGN(4);
  .bss :
  {
    /* This is used by the startup in order to initialize the .bss secion */
    _sbss = .;         /* define a global symbol at bss start */
    __bss_start__ = _sbss;
    *(.bss)
    *(.bss*)
    *(COMMON)

    . = ALIGN(8); //8字节对齐
    _ebss = .;         /* define a global symbol at bss end */
    __bss_end__ = _ebss;
    __heap_addr_end__ = ORIGIN(RAM) + LENGTH(RAM);  //主要是增加__heap_addr_end__ 。
    . = ALIGN(8);
  } >RAM

2. FreeRTOSConfig.h

FreeRTOSConfig.h中增加如下内容：

extern uint32_t __bss_end__;
extern uint32_t __heap_addr_end__;

3. 初始化

在main.c中增加如下内容：

static HeapRegion_t xHeapRegions[2];
int main(void)
{
    ...

    /* OS使用的内存 */
    xHeapRegions[0].pucStartAddress = (uint8_t *)(&__bss_end__);
    xHeapRegions[0].xSizeInBytes    = (uint8_t *)(&__heap_addr_end__) - (uint8_t *)(&__bss_end__);
    xHeapRegions[1].pucStartAddress = NULL;
    xHeapRegions[1].xSizeInBytes    = 0;
    vPortDefineHeapRegions(xHeapRegions);
    /* 初始化任务 */
    xTaskCreate(start_task_code, "start", START_TASK_STACK_SIZE, NULL, START_TASK_PRIORITY, &start_tid);

    vTaskStartScheduler();
    while (1) {

    }

}