diff --git a/Code/ESP32_communication/test_more_variables/ESP32_slave/ESP32_slave.ino b/Code/ESP32_communication/test_more_variables/ESP32_slave/ESP32_slave.ino
index a8fb476c622af264cb4e0ae062781358868191b3..22c233a8c581925e505763f38f49369acd365604 100644
--- a/Code/ESP32_communication/test_more_variables/ESP32_slave/ESP32_slave.ino
+++ b/Code/ESP32_communication/test_more_variables/ESP32_slave/ESP32_slave.ino
@@ -12,8 +12,8 @@ double Kpx=2, Kix=0.1, Kdx=0.25;
 double Kpy=1, Kiy=0.1, Kdy=0.25;
 int g1 = 0,g2=1,g3=2;
 int goal_id[3] = {g1, g2, g3};
-int Lmin = 30,Lmax = 100, Amin = -49,Amax = -22,Bmin = 31,Bmax = 127;
-int threshold[6] = {Lmin, Lmax, Amin, Amax, Bmin, Bmax};
+int8_t Lmin = 30,Lmax = 100, Amin = -49,Amax = -22,Bmin = 31,Bmax = 127;
+int8_t threshold[6] = {Lmin, Lmax, Amin, Amax, Bmin, Bmax};
 int base_speed = 70;
 int seeking_speed = 70;
 int lidar_thres = 300; // mm 
@@ -49,7 +49,24 @@ void setup()
 }
 //======================================================================================
 void loop()
-{ //-------------------PID-----------------
+{   ChangeVariables();
+     Serial.print("threshold:");
+    Serial.print(threshold[0]);
+    Serial.print("|");
+    Serial.print(threshold[1]);
+    Serial.print("|");
+    Serial.print(threshold[2]);
+    Serial.print("|");
+    Serial.print(threshold[3]);
+    Serial.print("|");
+    Serial.print(threshold[4]); 
+    Serial.print("|");   
+    Serial.println(threshold[5]);  
+}
+
+void ChangeVariables(){ 
+  // all the variables in this function can be remotely changed
+    //-------------------PID-----------------
   Kpx = getDoubleVal(strData,"kpx",valData,Kpx);
   Kix = getDoubleVal(strData,"kix",valData,Kix);
   Kdx = getDoubleVal(strData,"kdx",valData,Kdx);
@@ -81,6 +98,7 @@ void loop()
   seeking_speed = abs(getIntVal(strData,"ssp",valData,seeking_speed));
   lidar_thres = abs(getIntVal(strData,"lth",valData,lidar_thres));
   
+     /*
     Serial.print("base speed:");
     Serial.print(base_speed);
     Serial.print("|");
@@ -89,8 +107,8 @@ void loop()
     Serial.print("|");
     Serial.print("lidar thres:");
     Serial.println(lidar_thres);
-    
-  /*
+    */
+    /*
     Serial.print("threshold:");
     Serial.print(threshold[0]);
     Serial.print("|");
@@ -103,14 +121,15 @@ void loop()
     Serial.print(threshold[4]); 
     Serial.print("|");   
     Serial.println(threshold[5]);  
-  */
-  /*
+     */
+
+   /*
     Serial.print("gid:");
     Serial.print(goal_id[0]);
     Serial.print(goal_id[1]);
     Serial.println(goal_id[2]);
   */
-  /*
+    /*
     Serial.print("Kpx:");
     Serial.println(Kpx);
     Serial.print("Kix:");
@@ -123,7 +142,7 @@ void loop()
     Serial.println(Kiy);
     Serial.print("Kdy:");
     Serial.println(Kdy);
-*/
+  */
 }
 
 double getDoubleVal(String checkData,String Ans,double val,double ori_val){
@@ -141,7 +160,7 @@ int getIntVal(String checkData,String Ans,double val,int ori_val){
     strData = "";
     valData = 0.0;
     
-    return (int)val;
+    return (int8_t)val;
   }else {
     return ori_val;
   }