串口通信程序如何实现delete键的功能？

while(!(UART0->rUtrStat & 0x1)); //Receive data ready
           ch = UART0->rUrxh;
    
     if(ch == '\r')
     {
       while(!(UART0->rUtrStat & 0x2));  //wait utill transmit buffer empty
            UART0->rUtxh = '\n';
         while(!(UART0->rUtrStat & 0x2));  //wait utill transmit buffer empty
            UART0->rUtxh = '\r';      
          
     }
     else
     {
      if(ch == '\b')
         {
            while(!(UART0->rUtrStat & 0x2));  //wait utill transmit buffer empty
              UART0->rUtxh = '\b';
              while(!(UART0->rUtrStat & 0x2));  //wait utill transmit buffer empty
              UART0->rUtxh = ' ';
              while(!(UART0->rUtrStat & 0x2));  //wait utill transmit buffer empty
              UART0->rUtxh = '\b';          
         }
       else if(ch == 127)
       {
            Uart_Printf("11111111111111111111111111!\n\r");
       }
       else
           {
             while(!(UART0->rUtrStat & 0x2));
             UART0->rUtxh=ch;
           }


我的if（ch == 127）是用来判断delete键的，也有网上说是46，但是还是没用。我现在只用打印语句判断是否接受delete键传来的信号，具体怎么实现还没写。