K210 UART 921600

发布于 2019-08-30 10:01:02 浏览：1855 订阅该版

昨天跑通了K210的UART中断，可以收发数据了，尝试了下921600的速率，数据2，3十个发的时候就会丢数据，感觉底层驱动改的有些问题，看了下论坛里的帖子，说921600需要用DMA接收才不会丢数据。。

uart中断函数

```/* UART ISR */
static void uart_irq_handler(int irqno, void *param)
{
    rt_ubase_t isr;
	uint8_t v_int_status;
    struct rt_serial_device *serial = (struct rt_serial_device *)param;
    struct device_uart *uartls = serial->parent.user_data;

/* read interrupt status and clear it 
    if (uart->hw_base == UARTHS_BASE_ADDR)
    {
        if (uarths->ip.rxwm) 
            rt_hw_serial_isr(serial, RT_SERIAL_EVENT_RX_IND);
    }*/

if(irqno == IRQN_UARTHS_INTERRUPT)
	{
		if (uarths->ip.rxwm) 
            rt_hw_serial_isr(serial, RT_SERIAL_EVENT_RX_IND);
	}
	else
	{
		v_int_status = uart[serial->config.uart_num]->IIR & 0xF;
		if(v_int_status == UART_INTERRUPT_SEND )
			rt_hw_serial_isr(serial, RT_SERIAL_EVENT_TX_DONE);
  		else if(v_int_status == UART_INTERRUPT_RECEIVE || v_int_status == UART_INTERRUPT_CHARACTER_TIMEOUT)
			rt_hw_serial_isr(serial, RT_SERIAL_EVENT_RX_IND);	
	}
}```
中断在这里接收数据
```/* ISR for serial interrupt */
void rt_hw_serial_isr(struct rt_serial_device *serial, int event)
{
    switch (event & 0xff)
    {
        case RT_SERIAL_EVENT_RX_IND:
        {
            int ch = -1;
            rt_base_t level;
            struct rt_serial_rx_fifo* rx_fifo;

/* interrupt mode receive */
            rx_fifo = (struct rt_serial_rx_fifo*)serial->serial_rx;
            RT_ASSERT(rx_fifo != RT_NULL);

while (1)
            {
                ch = serial->ops->getc(serial);
                if (ch == -1) break;```
K210底层函数
```int uartapb_getc(uart_device_number_t channel)
{
    if(uart[channel]->LSR & 1)
        return (char)(uart[channel]->RBR & 0xff);
    else
        return -1;

/* while (!(uart[channel]->LSR & 1))
        continue;
    return (char)(uart[channel]->RBR & 0xff);*/
}```
原本底层函数为屏蔽的那一段，但那样没有数据的时候，会死在while中，改成if判断，那样发现每获取一个字节，都会进两次uartapb_getc，感觉这个底层驱动有点问题。