求助：BUS FAULT

发布于 2014-07-30 16:48:38 浏览：4358 订阅该版

我在工程中加入一个新的线程后串口就会打印出如下信息
```psr: 0x21000000
r00: 0x2000ab58
r01: 0x10000000
r02: 0xf0000000
r03: 0x00000020
r04: 0x00000000
r05: 0x00000000
r06: 0xfffffffc
r07: 0x2000fd28
r08: 0x00000001
r09: 0x00000000
r10: 0xdeadbeef
r11: 0x00000000
r12: 0x00000000
 lr: 0x0800ff9d
 pc: 0x0800ff9c
hard fault on thread: mp2

thread  pri  status      sp     stack size max used   left tick  error
-------- ---- ------- ---------- ---------- ---------- ---------- ---
tidle    0x1f ready   0x00000040 0x00000100 0x00000060 0x0000000f 000
tshell   0x0c suspend 0x00000090 0x00000800 0x00000090 0x0000000a 000
mp2      0x06 ready   0x000000a8 0x00000800 0x000000e0 0x00000014 000
fc8080   0x05 suspend 0x00000078 0x00001000 0x00000108 0x00000014 000
isr      0x07 ready   0x00000078 0x00000400 0x000000d0 0x00000014 -02
frame    0x08 suspend 0x000000d8 0x00000400 0x00000240 0x0000000f 000
bus fault:
SCB_CFSR_BFSR:0x82 PRECISERR SCB->BFAR:FFFFFFFC```

hard fault的PC值指向的函数是rt_hw_context_switch_to((rt_uint32_t)&to_thread->sp);之后的地方，该怎么找问题？！
请问bus fault该如何理解？

5 个回答

pangwei 2014-07-31

这家伙很懒，什么也没写！

Zitral 2014-07-31

这家伙很懒，什么也没写！

>自己线程是不是有非法操作。得看代码才行

---

之前用的是STM32F205单片机，没有这个问题，现在用的是GD32F103（兼容STM32F103），下面是mp2代码

```
#include <rtthread.h>
#include <finsh.h>
//#include <dfs_posix.h>

#include "global.h"

#include "decoder.h"
//#include "dab_fifo.h"
#include "dab_packet.h"
#include "dec_callback.h"
#include "audio.h"

states:

DEC_IDLE
DEC_MP2_INIT
DEC_MP2_NOR
DEC_MP2_FINISH
DEC_AAC_INIT
DEC_AAC_HEAD
DEC_AAC_NOR
DEC_AAC_FINISH
DEC_SWITCH

#define MP2_PCM_SIZE        (1152*2*2)
#define AAC_PCM_SIZE        (2048*2*2)

#define DEC_STATE_IDLE  0
//#define DEC_STATE_CHK   0
#define DEC_STATE_NOR   1
int level_t;

DAB_PACKET packet;
uint16_t packet_offset;

extern void AUDIO_DACDMAConfig(void * pbuffer,uint32_t buffersize,int inc);

int DAB_MP2Read(unsigned char *pbuf,int bytec)
{
  int i, size_t;
  //rt_kprintf("%4d, %4d
", packet_offset, bytec);
  size_t = ((packet_offset + bytec) > packet.size)?
    (packet.size - packet_offset): bytec;
  for(i = 0; i < size_t; i++)
  {
    pbuf[i] = packet.payload[packet_offset + i];
  }
  packet_offset += i;
  return size_t;
}

extern void mp2_thread_entry(void* parameter)
{
  int dec_state=0;
  rt_mp_t mp2_mp;
  uint32_t val;
  int err;
  int first_frame;
  
  void * poutbuffer=RT_NULL;
  void * mp2_mp_data;
  rt_device_t dev=RT_NULL;

//mp2_mp
  mp2_mp_data=rt_malloc((MP2_PCM_SIZE+4)*2);
  mp2_mp=rt_malloc(sizeof(struct rt_mempool));
  //
  err=rt_mp_init(mp2_mp,"mp2",mp2_mp_data,(MP2_PCM_SIZE+4)*2,MP2_PCM_SIZE);
  if(err!=RT_EOK)
    goto mp2_exit;
  //dev
  dev=rt_device_find("aud");
  if(dev==RT_NULL)
  {
    rt_kprintf("can't find device aud
");
    goto mp2_exit;
  }
  err=rt_device_open(dev,RT_DEVICE_FLAG_RDONLY);
  if((err==RT_EOK)||(err==-RT_EBUSY))
  {
    rt_kprintf("aud open successed
");
    val=48000;
    rt_device_control(dev,AUDIO_SET_SAMPLERATE,&val);
  }
  else 
    goto mp2_exit;
  crcdisable = 0;  
  DecoderInit(DAB_MP2Read);
  
/**********************/
  first_frame = 1;
  while(1)
  {
    val = DAB_Packet_Take(&packet);
    if(val != 0)
    {
      rt_thread_delay(1);
      continue;
    }
    //rt_kprintf("packet got
");
    if(packet.type != 0)
    {
      rt_kprintf("not support
");
      DAB_Packet_Release(&packet);
      continue;
    }
    
    packet_offset = 0;
    val = DecodeFrame(0);
    if(val != 0)
    {
      rt_kprintf("frame err %d
", val);
      first_frame = 1;
      DAB_Packet_Release(&packet);
      continue;
    }
    DAB_Packet_Release(&packet);
    if(first_frame)
    {
      uint32_t fs = DecoderGetSample();
      rt_device_control(dev,AUDIO_SET_SAMPLERATE,&fs);
      first_frame = 0;
    }
    poutbuffer = rt_mp_alloc(mp2_mp,RT_WAITING_FOREVER);
    rt_memcpy(poutbuffer,AudioBuffer,MP2_PCM_SIZE);
//		if(FLAGS.AACDMA_Init==0)
//			{
//				//InitDMA_FORDAB();
//				AUDIO_DACDMAConfig(poutbuffer,MP2_PCM_SIZE/4,1);
//				//FLAGS.AACDMA_Init=1;
//			}
    rt_device_write(dev,0,poutbuffer,MP2_PCM_SIZE);
  }
/**********************/
mp2_exit:
  if(mp2_mp!=RT_NULL)
  {
    void * p1;
    p1=rt_mp_alloc(mp2_mp,RT_WAITING_FOREVER);
    if(p1!=RT_NULL)
      rt_mp_free(p1);
    rt_mp_detach(mp2_mp);
    rt_free(mp2_mp);
  }
  if(mp2_mp_data!=RT_NULL)rt_free(mp2_mp_data);
  if(dev!=0)rt_device_close(dev);
}
```