private static byte byteToBcd(int incomingByte) {
        byte dec = (byte) ((incomingByte / 10) % 10);
        return (byte) ((dec << 4) | (incomingByte % 10));
    }
converts incoming byte to an integer regarding used BCD format

@param incomingByte the incoming byte
@return converted BCD number
plc4j/drivers/s7/src/main/java/org/apache/plc4x/java/s7/readwrite/utils/StaticHelper.java