case 0x1b: pwm1=40;
pwm2=40;
straight(); //P0.0|P0.1|P0.2|P0.3|P0.4为11011说明小车正常寻迹下一步小车直行
break;
case 0x1d: //P0.0|P0.1|P0.2|P0.3|P0.4为11101说明小车左偏下一步小车右拐
pwm2=30;
pwm1=30;
turn_right();
break;
case 0x17: //10111
pwm2=35;
pwm1=35;
turn_left();
//P0.0|P0.1|P0.2|P0.3|P0.4为10111说明小车右偏下一步左拐
break;
case 0x03:
pwm1=50;
pwm2=50;
straight();
delay(1);
//P1.0|P1.1|P1.2|P1.3|P1.4为00011说明小车遇到左T标置物小车左拐
pwm1=30;
pwm2=40;
turn_left();
break;
case 0x18:
pwm1=50;
pwm2=50;
straight();
delay(1);
//P0.0|P0.1|P0.2|P0.3|P0.4为11000说明小车遇到右T标志物下一步小车右拐
pwm1=40;
pwm2=40;
turn_right();
break;
case 0x11: //P0.0|P0.1|P0.2|P0.3|P0.4为00001说明小车遇到十字标志物下一步直行
case 0x10: //P0.0|P0.1|P0.2|P0.3|P0.4为10001说明小车遇到十字标志物体下一步小车直行
case 0x01: //P0.0|P0.1|P0.2|P0.3|P0.4为10000说明小车遇到十字标志物下一步直行
case 0x00: //P0.0|P0.1|P0.2|P0.3|P0.4为00000说明小车遇到十字标志物下一步小车直行