Used as a Bluetooth remote control for Arduino.

Code for Arduino;
#include
const int sensorIn = A0;
int mVperAmp = 66; // use 100 for 20A Module and 66 for 30A Module
int port1=2,port2=3,port3=4,port4=5,port5=6,port6=7,port7=8,port8=9;

double Voltage = 0;
double VRMS = 0;
double AmpsRMS = 0;

void setup(){
Serial.begin(9600);
pinMode(port1, OUTPUT);
pinMode(port2, OUTPUT);
pinMode(port3, OUTPUT);
pinMode(port4, OUTPUT);
pinMode(port5, OUTPUT);
pinMode(port6, OUTPUT);
pinMode(port7, OUTPUT);
pinMode(port8, OUTPUT);

}

void loop(){
while (Serial.available() > 0) {
int inByte = Serial.read();

switch (inByte) {
case 'a':
digitalWrite(port1,HIGH);
break;
case 'b':
digitalWrite(port1,LOW);
break;

case 'c':
digitalWrite(port2,HIGH);
break;
case 'd':
digitalWrite(port2,LOW);
break;

case 'e':
digitalWrite(port3,HIGH);
break;
case 'f':
digitalWrite(port3,LOW);
break;

case 'g':
digitalWrite(port4,HIGH);
break;
case 'h':
digitalWrite(port4,LOW);
break;

case 'i':
digitalWrite(port5,HIGH);
break;
case 'j':
digitalWrite(port5,LOW);
break;

case 'k':
digitalWrite(port6,HIGH);
break;
case 'l':
digitalWrite(port6,LOW);
break;

case 'm':
digitalWrite(port7,HIGH);
break;
case 'n':
digitalWrite(port7,LOW);
break;

case 'o':
digitalWrite(port8,HIGH);
break;
case 'p':
digitalWrite(port8,LOW);
break;
}

}

Voltage = getVPP();
VRMS = (Voltage/2.0) *0.707;
AmpsRMS = (VRMS * 1000)/mVperAmp;
Serial.print("\n");
}

float getVPP()
{
float result;
int readValue; //value read from the sensor
int maxValue = 0; // store max value here
int minValue = 1024; // store min value here

uint32_t start_time = millis();
while((millis()-start_time) < 1000) //sample for 1 Sec
{
readValue = analogRead(sensorIn);
// see if you have a new maxValue
if (readValue > maxValue)
{
/*record the maximum sensor value*/
maxValue = readValue;
}
if (readValue < minValue)
{
/*record the maximum sensor value*/
minValue = readValue;
}
}

// Subtract min from max
result = ((maxValue - minValue) * 5.0)/1024.0;

return result;
}