PLS 62-W EEPROM (AT24C08) with Interface I2cBusConnection | Telit Cinterion IoT Developer Community

Hello Bartłomiej

Initially I used the Java documentation example:

I2cBusConnection cc = (I2cBusConnection) Connector.open("i2c:0;baudrate=100") -> or 400;

 
 InputStream inStream  = cc.openInputStream();
 OutputStream outStream = cc.openOutputStream()

Write Transfer Frame, where a = message ID, AE = Slave Address and write request:

 String data = "<AA0000005>"; -> message sent to eeprom memory
 outStream.write(data.getBytes(), 0, data.length());
 outStream.flush();
 

Read response message: {a+} where a = message ID:

 byte[] inBuf = new byte[10];
 if (inStream.available())
  int inBufLen = inStream.read(inBuf); 

  String response = byteArrayToHexString(inBuf);

checkResponseAck(response);

System.out.printl(response);

If the memory is connected to the module the answer is {+} its disconnected to the power the answer is {-} but I'm a little confused the documentation is not very explanatory

Aux methods

private boolean checkResponseAck(String responseIn) {
        final boolean DEBUG = false;
        boolean retVal = false;

        if (DEBUG) {System.out.println("[I2CHandler]: I2C response = " + responseIn);}
       
        if (responseIn != null) {
            retVal = true;

            // Response Message: (AT Command guide - Table 19.3)
            // {ID + }         Write OK
            // {ID + Data }    Read of x bytes OK
            // {ID - **** }    NAK for xth byte if Read or Write
            // {ID ! **** }      Protocol error in xth byte

            if (responseIn.indexOf("{a+") == -1) {
                retVal = false;
               
                if (responseIn.indexOf("{a-") > -1) {
                    if (DEBUG) {System.out.println("[I2CHandler]: I2C command not acknowledged: '" + responseIn + "'");}
                }
               
                if (responseIn.indexOf("{a!") > -1) {
                    System.out.println("[I2CHandler]: I2C command protocol error: '" + responseIn + "'");
                }
            }
        } else {
            System.out.println("[I2CHandler]: Warning checkResponseAck() called but responseIn == null");
        }
       
        return retVal;
    }

// This will give two-char length string for an int.
    public String intToHex(int i){
        final char[] Hex = "0123456789ABCDEF".toCharArray();
       
        return  "" + Hex[(i & 0xF0) >> 4] + Hex[(i & 0x0F)];
    }
   
// This will give multiple two-char pairs string for a byte array.
    public String byteArrayToHexString(byte[] bytes) {
        char[] hexChars = new char[bytes.length * 2];
        int v;
       
        for ( int j = 0; j < bytes.length; j++ ) {
            v = bytes[j] & 0xFF;
            hexChars[j*2] = HEX_ARRAY[v/16];             // method 1
            hexChars[j*2 + 1] = HEX_ARRAY[v%16];         // method 1
        }
       
        return new String(hexChars);
    }
       

public static String byteArrayToHexString(byte[] bytesIn) {
        final char[] HEX_ARRAY = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
        char[] hexChars;
        int j;
        int v;

        if (bytesIn != null) {
            hexChars = new char[bytesIn.length * 2];

            for (j = 0; j < bytesIn.length; j++) {
                v = bytesIn[j] & 0xFF;
                hexChars[j * 2] = HEX_ARRAY[v / 16];
                hexChars[j * 2 + 1] = HEX_ARRAY[v % 16];
            }
            return new String(hexChars);
        } else {
            System.out.println("[Modbus]: byteArrayToHexString() null pointer.");
            return null;
        }
    }