还是串口收发的问题

发布于 2012-07-24 11:52:13 浏览：3996 订阅该版

7 个回答

bernard 2012-07-24

这家伙很懒，什么也没写！

lujun723 2012-07-24

这家伙很懒，什么也没写！

```
static void rs485_thread_entry(void* parameter)
{
	extern rt_size_t rt_serial_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size);
	extern rt_size_t rt_serial_read (rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size);
	extern struct rt_device uart1_device;
	rt_size_t length;
	uint16_t cnt;

rs485_init();
	length=10;

while (1)
    {
		rs485_rx_on();
                cnt=50000;
		while(cnt--);
		rt_device_read(&uart1_device,0,in,length);
		rt_thread_delay( 50 );

rs485_tx_on();
		cnt=50000;
		while(cnt--);
		rt_device_write(&uart1_device,0,in,length); 
                rt_thread_delay( 50 );
    }
}

void rs485_init(void)
{
	GPIO_InitTypeDef GPIO_InitStructure;
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);	
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11|GPIO_Pin_12;          
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; 
	GPIO_Init(GPIOA, &GPIO_InitStructure);
}

void rs485_rx_on(void)
{
	GPIO_ResetBits(GPIOA,  GPIO_Pin_11);	
	GPIO_ResetBits(GPIOA,  GPIO_Pin_12);
}

void rs485_tx_on(void)
{
	GPIO_SetBits(GPIOA,  GPIO_Pin_11);	
	GPIO_SetBits(GPIOA,  GPIO_Pin_12);
}

void USART1_IRQHandler(void)
{
#ifdef RT_USING_UART1
    extern struct rt_device uart1_device;
	extern void rt_hw_serial_isr(struct rt_device *device);

/* enter interrupt */
    rt_interrupt_enter();
	
    rt_hw_serial_isr(&uart1_device);

/*leave interrupt */
    rt_interrupt_leave();
#endif
}

```