For the Arduino code, we include the wire library. Then in the Arduino loop we first use Wire.requestFrom(“ATtiny Address”,”number of bytes being received”) to request a certain number of bytes from the ATtiny85. We then use Wire.read(); to read the byte being sent over. Once we obtain the high and low bytes, we combine both bytes to form a 10 bit value. We then turn this 10 bit value to an actual voltage/current/temperature value. For voltage we use, voltage = (Vin*1024)/Vref. For current we use current = (Current_in*1024)/(10*shunt_resistor). For temperature we use Temperature_F = ((Temp_in-273.15)*1.8)+32. For power we use P=V*I. See code below.

//Attiny85 Slave Address
#define SLAVE_ADDR 0x30      //Attiny85 Address
#define SLAVE_ADDR_2 0x31    //Attiny85 Address
#define SLAVE_ADDR_3 0x32    //Attiny85 Address
#define SLAVE_ADDR_4 0x33    //Attiny85 Address

//Array 1
uint16_t Current_10;
uint16_t Voltage_10;
uint16_t Temp_10;

//Array 2
uint16_t Current_10_2;
uint16_t Voltage_10_2;
uint16_t Temp_10_2;

// repeat for additional modules

float ten_bit = 1023;
const int RS = 10;                // Shunt resistor value (in ohms)
const int VOLTAGE_REF = 1.1;      // Reference voltage for analog read
const float ratio = 0.0010752688; // each bit is (Vref/1023) V

// Array 1
float Current;       //current variable
float Voltage;       //voltage variable
float Power;         //power variable
float Temperature_F; //Temperature in Fahrenheit

// Array 2
float Current_2;       //current variable
float Voltage_2;       //voltage variable
float Power_2;         //power variable
float Temperature_F_2; //Temperature in Fahrenheit

// repeat for additional modules

void setup()
{
  Wire.begin();       // join i2c bus (address optional for master)
  Serial.begin(9600); // start serial for output
}

void loop()
{
  // Module 1
  Wire.requestFrom(SLAVE_ADDR,6);        // request 6 bytes from Attiny85 device address 4
  if (Wire.available())                  // slave may send less than requested
  {
    uint8_t temp_low = Wire.read();        // receive a byte as character
    uint8_t temp_high = Wire.read();       // receive a byte as character
    uint8_t voltage_low = Wire.read();     // receive a byte as character
    uint8_t voltage_high = Wire.read();    // receive a byte as character
    uint8_t current_low = Wire.read();     // receive a byte as character
    uint8_t current_high = Wire.read();    // receive a byte as character

    // combining bytes 10 bit
    Current_10 = ((current_high << 8) | current_low);
    Voltage_10 = ((voltage_high << 8) | voltage_low);
    Temp_10 = ((temp_high << 8) | temp_low);
    Temp_10 = Temp_10 - 20;

    // Current bit to Value
    Current = (Current_10 * VOLTAGE_REF)/ten_bit;
    Current = Current/(10 * RS);

    // Voltage bit to value
    Voltage = Voltage_10*ratio*45.83333333333;  //10.4792528736;

    // Power Calculation
    Power= Voltage*Current;

    // Temp bit to Fahrenheit
    Temperature_F = ((Temp_10-273.15)*1.8)+32; //temp is Fahrenheit

    Serial.println("Module 1");
    Serial.print("Voltage:    ");
    Serial.print(Voltage,5);
    Serial.println(" V");
    Serial.print("Current:    ");
    Serial.print(Current,5);
    Serial.println(" A");
    Serial.print("Power:      ");
    Serial.print(Power,5);
    Serial.println(" W");
    Serial.print("Temp:       ");
    Serial.print(Temperature_F,5);
    Serial.println(" F");
    Serial.println("");
    Serial.println("");
   delay(1000);
  }

  // Module 2
  Wire.requestFrom(SLAVE_ADDR_2,6);        // request 6 bytes from Attiny85 device address 4

  if (Wire.available())                    // slave may send less than requested
  {
    // use module 1 as a template 
  }
  // repeat for modules 3 and 4

delay(1000);
}