lpc176x移植包串口接收没有错误处理

发布于 2010-12-16 19:49:00 浏览：3403 订阅该版

lpc176x移植包串口接收没有错误处理，导致接收数据出错时中断无法清除。参照官方例程改动如下：

> 
//
t-threadsplpc176xuart.c
void UART0_IRQHandler(void)
{
	rt_ubase_t level, iir;
    struct rt_uart_lpc* uart = &uart_device;

/* read IIR and clear it */
	iir = LPC_UART->IIR;

iir >>= 1;			    /* skip pending bit in IIR */
	iir &= 0x07;			/* check bit 1~3, interrupt identification */

if (( iir == IIR_RLS && (LPC_UART0->LSR & LSR_RDR) ) || iir == IIR_RDA)	    /* Receive Data Available */
	{
		/* Receive Data Available */
        uart->rx_buffer[uart->save_index] = LPC_UART->RBR;

level = rt_hw_interrupt_disable();
		uart->save_index ++;
        if (uart->save_index >= RT_UART_RX_BUFFER_SIZE)
            uart->save_index = 0;
        rt_hw_interrupt_enable(level);

/* invoke callback */
		if(uart->parent.rx_indicate != RT_NULL)
		{
		    rt_size_t length;
		    if (uart->read_index > uart->save_index)
                length = RT_UART_RX_BUFFER_SIZE - uart->read_index + uart->save_index;
            else
                length = uart->save_index - uart->read_index;

uart->parent.rx_indicate(&uart->parent, length);
		}
	}
	else if ( iir == IIR_RLS && (LPC_UART0->LSR & (LSR_OE|LSR_PE|LSR_FE|LSR_RXFE|LSR_BI)) )
	{
		uart->rx_buffer[uart->save_index] = LPC_UART->RBR;	/*Dummy read on RX to clear interrupt*/
	}

return;
}