unsigned char ch ;
ch = PTT&0x0F; //读取T口拨码开关的值
switch(ch) {
case '0x00':RTICTL = 0x0F;break; //6.10Hz
case '0x01':RTICTL = 0x1F;break;
case '0x02':RTICTL = 0x2F;break;
case '0x03':RTICTL = 0x3F;break;
case '0x04':RTICTL = 0x4F;break;
case '0x05':RTICTL = 0x5F;break;
case '0x06':RTICTL = 0x6F;break;
case '0x07':RTICTL = 0x7F;break; //1.526Hz,中断频率逐渐减小
case '0x08':RTICTL = 0x8F;break; //中断频率1000Hz
case '0x09':RTICTL = 0x9F;break;
case '0x0A':RTICTL = 0xAF;break;
case '0x0B':RTICTL = 0xBF;break;
case '0x0C':RTICTL = 0xCF;break;
case '0x0D':RTICTL = 0xDF;break;
case '0x0E':RTICTL = 0xEF;break;
case '0x0F':RTICTL = 0xFF;break; //5Hz,中断频率逐渐减小