20 [freemodbus]进入断言

发布于 2022-11-03 17:25:14 浏览：614 订阅该版

使用freemodbus时断言 RT_ASSERT( eRcvState == STATE_RX_IDLE ). 想查是什么原因, 故将此断言屏蔽, 然后添加打印信息

```c
BOOL
xMBRTUTransmitFSM( void )
{
    BOOL            xNeedPoll = FALSE;

//RT_ASSERT( eRcvState == STATE_RX_IDLE );
    rt_enter_critical();
    
    if((int)eRcvState != 1)
    {
        rt_kprintf("r%xr",(int)eSndState);
        if((int)eRcvState != 1)
        {
            rt_kprintf("c%dc",(int)eRcvState);
        }
    }
    rt_exit_critical();

switch ( eSndState )
    {
        /* We should not get a transmitter event if the transmitter is in
         * idle state.  */
    case STATE_TX_IDLE:
        /* enable receiver/disable transmitter. */
        vMBPortSerialEnable( TRUE, FALSE );
        break;

case STATE_TX_XMIT:
        /* check if we are finished. */
        if( usSndBufferCount != 0 )
        {
            xMBPortSerialPutByte( ( CHAR )*pucSndBufferCur );
            pucSndBufferCur++;  /* next byte in sendbuffer. */
            usSndBufferCount--;
        }
        else
        {
            xNeedPoll = xMBPortEventPost( EV_FRAME_SENT );
            /* Disable transmitter. This prevents another transmit buffer
             * empty interrupt. */
            vMBPortSerialEnable( TRUE, FALSE );
            eSndState = STATE_TX_IDLE;
        }
        break;
    }

return xNeedPoll;
}
```

但是发现很奇怪的现象, 如图:

![企业微信截图_16674674764858.png](https://oss-club.rt-thread.org/uploads/20221103/5e0acf4f2bd6d955928d1ce2e4d54b85.png.webp "企业微信截图_16674674764858.png")

但是从逻辑上分析, 进入时eRcvState一定为1.

想问下什么情况会出现此现象.

加了临界区, 所以应该没有别的线程能改, 然后查了所有线程的内存, 没有溢出现象