// ------------------------------------------
// AI Thinker A1S Chip identifier for Arduino
// i2c_scanner Easy LED detection
// AC101  LED 4 is high   (next to earphone jack)
// ES8388 LED 5 is active (next to earphone jack)
// Serial messages 115200 are also available
// Friedemann Wolpert 2021
 
#include <Wire.h>

const byte led_5 = 19;
const byte led_4 = 22;

void setup()
{
  bool bFound = false;
  Wire.begin(33, 32);  // Begin with AC-101  Audio Codec Chip

  pinMode(led_4, OUTPUT);
  pinMode(led_5, OUTPUT);
  
  Serial.begin(115200);
  Serial.println("\nsetup() finished\n");

  digitalWrite(led_4, HIGH);   // turn the LED on (HIGH is the voltage level)
  digitalWrite(led_5, HIGH);   // turn the LED on (HIGH is the voltage level)

  delay(1000);                 // LED`s should be off after reset
}

void loop()
{
  byte error, address;
  int nDevices;
 
  Serial.println("Scanning AC-101 address...");
  Wire.begin(33, 32);  // AC-101  Audio Codec Chip

  nDevices = 0;
  for(address = 1; address < 127; address++ )
  {
    // The i2c_scanner uses the return value of
    // the Write.endTransmisstion to see if
    // a device did acknowledge to the address.
    Wire.beginTransmission(address);
    error = Wire.endTransmission();
 
    if (error == 0)
    {
      Serial.print("AC-101 I2C device found at address 0x");
      digitalWrite(led_4, LOW);   // turn LED4 on
      if (address<16)
        Serial.print("0");
      Serial.print(address, HEX);
      Serial.println("  !");
      nDevices++;
    }
    else if (error==4)
    {
      Serial.print("Unknown error at address 0x");
      if (address<16)
        Serial.print("0");
      Serial.println(address,HEX);
    }    
  }
  
  delay (250);

  Serial.println("Scanning ES-8388 address...");
  Wire.begin(18, 23);  // ES-8388  Audio Codec Chip
 
  nDevices = 0;
  for(address = 1; address < 127; address++ )
  {
    // The i2c_scanner uses the return value of
    // the Write.endTransmisstion to see if
    // a device did acknowledge to the address.
    Wire.beginTransmission(address);
    error = Wire.endTransmission();
 
    if (error == 0)
    {
      Serial.print("ES-8388 I2C device found at address 0x");
      digitalWrite(led_5, LOW);   // turn LED5 on
      if (address<16)
        Serial.print("0");
      Serial.print(address, HEX);
      Serial.println("  !");
      nDevices++;
    }
    else if (error==4)
    {
      Serial.print("Unknown error at address 0x");
      if (address<16)
        Serial.print("0");
      Serial.println(address,HEX);
    }    
  }

  if (nDevices == 0)
    Serial.println("No I2C devices found\n");
  else
    Serial.println("done\n");
 
  delay(5000);           // wait 5 seconds for next scan
}