这是官网提供的例程代码，直接用if或者switch语句判断sbuf就可以了，

把P0口改成接收数据的缓存如temp，详细的参考STC-SPI软件自带例程：

/*----------------------------
UART2 interrupt service routine
----------------------------*/
void Uart2() interrupt 8 using 1
{
    if (S2CON & S2RI)
    {
        S2CON &= ~S2RI;     //Clear receive interrupt flag
        P0 = S2BUF;         //P0 show UART data
        P2 = (S2CON & S2RB8);//P2.2 show parity bit
    }
    if (S2CON & S2TI)
    {
        S2CON &= ~S2TI;     //Clear transmit interrupt flag
        busy = 0;           //Clear transmit busy flag
    }
}