void check_serial()
{

byte testax=2;
  
while (Serial.available() > 0) {
    // get incoming byte:
    inByte = Serial.read();
    boolean isaxcmd=false;
    if (inByte!=10) {rec+=(char)inByte;}
    else 
    {
//      Serial.println("got:'"+rec+"'");
      rec.trim();
      int p=rec.indexOf(' ');
      String cmd=rec.substring(0,p);
      String param=rec.substring(rec.indexOf(' ')+1);
      char aparam[param.length() + 1];
      param.toCharArray(aparam, sizeof(aparam));
      int iparam = atoi(aparam); 

      #ifdef debug 
      Serial.print("cmd: ");Serial.println(cmd);
      Serial.print("param: ");Serial.println(param);
      #endif
      
      //Serial.println(iparam);
      
      //return:
      if (cmd.length()==0)
      {
         #ifdef info 
          Serial.println("emergency off");
          pos_to_eeprom();
         #endif
         mot_off(testax); speed[testax]=null_speed;
      }
  
      isaxcmd=false;

if (cmd=="?") print_positions();

/*
      if (cmd=="a") {mot_on(testax);Serial.println("mot_on:"+String(testax));}
      else
      if (cmd=="b") {mot_off(testax);speed[testax]=null_speed;  set_ltc();Serial.println("mot_off:"+String(testax));}
      else

*/
    
      if (cmd=="c") 
        {speed[testax]+=10;
         Serial.println(speed[testax]-null_speed);
         set_motors();
        }
      else
      if (cmd=="d") 
        {speed[testax]-=10;
         Serial.println(speed[testax]-null_speed);
         set_motors();}
      else
      if (cmd=="h") {home(0);}

      else

      if (cmd=="p") {
        target[0]=10000;
//        goposax(0);
        }
      else
      if (cmd=="q") {
        target[0]=33000;
//        goposax(0);
        }
      else
      if (cmd=="o") {
        target[0]=55000;
//        goposax(0);
        }

      else 
      if (cmd=='e') {
        Serial.println("got e, saving to eeprom");
        pos_to_eeprom();
        }

else
        
      if (cmd=="r") 
        {
randomizetargets();     
        }
      else
        
      if (cmd=="s") 
        {
        
        issequence=!issequence;
        if (issequence)
        {
          Serial.println("sequence ON"); 
          target[0]=targets[0][0];
//          goposax(0);
        }
        else
        {
          Serial.println("sequence OFF");
        }
        
        }
              
      rec="";  
    }

}
}