APC220 Problem Communicating with each other (PC to Arduino or viceversa)

Hello arduino-er, just bought mine last week and having an awesome time for it.
here is my quick questions.

  1. Arduino detect COM3(my com port) but i cant seem to send any command to arduino.
  2. I tried uploading the code using apc220, also failed (i noticed the 256bytes capabilities, but just trying).
  3. My code runs fine when using usb-powered at computer, but it wont run if i used adapter(the adapter is also using usb-cable to power the arduino). I set the code to blink once every loop for test purpose.
  4. I have no way of knowing if arduino is transferring data to my pc, since i cant even send from pc to arduino, much less test the reverse. Is there any way i can test if the arduino is transferring any data using COM3?
  5. I heard you cannot used usb-powered if i want to use APC220. Is that true? Do i need a battery then?
const int trigPin = 2;
const int echoPin = 4;
float temp;
int tempPin = 0;

void setup() {
  Serial.begin(9600);
}

void loop()
{  
    delay(1000);
    room_heat_sensor();
    delay(1000);
    ultrasonic_sensor();
  
}

void room_heat_sensor()
{
  temp = analogRead(tempPin);
  temp = temp * 0.48828125;
  Serial.print(temp);
  Serial.println();
}

void ultrasonic_sensor()
{
  long duration, inches, cm;
 
  pinMode(trigPin, OUTPUT);
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
 
  pinMode(echoPin, INPUT);
  duration = pulseIn(echoPin, HIGH);
 
  inches = microsecondsToInches(duration);
  cm = microsecondsToCentimeters(duration);
  
  Serial.print(inches);
  Serial.print("in, ");
  Serial.print(cm);
  Serial.print("cm");
  Serial.println();
}

long microsecondsToInches(long microseconds)
{
  return microseconds / 74 / 2;
}

long microsecondsToCentimeters(long microseconds)
{
  return microseconds / 29 / 2;
}

p/s : i didnt connect the heat sensor and ultrasonic sensor in the pic below, but it still gives me random gibberish data continuously nonetheless.





Below is some of the instruction i've followed
http://www.swanrobotics.com/Wireless_Arduino
http://fritzing.org/projects/wireless-arduino-with-apc220
http://www.appconwireless.com/NEWS/shownews.php?lang=en&id=6
and many others.

Any help is very much appreciated :slight_smile: