Implementation help for SparkFun_RV-8803_Library using this i2c lib instead of std Wire lib

[dattasaurabh82]

Hello! First of all, thank you for this low mem lib implementation as alt to std wire lib.

This is not really an issue report.
I'm trying to implement SparkFun_RV-8803_Arduino_Library using this library:

I'm wondering, form having read a bit this repo, some method comparison would be, for example, from SparkFun_RV8803.cpp, for some functions:

//--- READ OPERATIONS [ as laid out in datasheet 6.8 ]  ---//
uint8_t RV8803Tiny::readRegister(uint8_t addr) {
  //------------------------------------------------------------------------------------//
  //--- using std wire library in custom class as depicted from the sparkfun library ---//
  //------------------------------------------------------------------------------------//
  // ---- [ lines 693-706 in sparkfun library ]
  
  //  _i2cPort->beginTransmission(RV8803_ADDR);
  //  _i2cPort->write(addr);
  //  _i2cPort->endTransmission();
  //
  //  //typecasting the 1 parameter in requestFrom so that the compiler
  //  //doesn't give us a warning about multiple candidates
  //  if (_i2cPort->requestFrom(static_cast<uint8_t>(RV8803_ADDR), static_cast<uint8_t>(1)) != 0)
  //  {
  //    return _i2cPort->read();
  //  }
  //  return false;



  //------------------------------------------------------------------------------------//
  //------------------ using tiny-mega-wire library in custom class --------------------//
  //------------------------------------------------------------------------------------//
  //  Master sends out the START condition, signifyig it'll be a write operation [ R/W bit is a 0 ]
  if (TinyMegaI2C.start(RV8803_ADDR, 0)) { //  if Acknowledged from RV-8803
    //  Master sends out the Register Address to RV-8803-C7.
    if (TinyMegaI2C.write(addr)) { //  if Acknowledged from RV-8803
      //  Master sends out the Repeated START condition (or STOP condition followed by START condition)
      //  Master sends out Slave Address, 65h for the RV-8803 [ R/W bit is 1 ] indicating a read operation
      if (TinyMegaI2C.restart(RV8803_ADDR, 1)) { //Acknowledgement from RV-8803-C7
        // The Slave sends out the Data from the Register Address
        uint8_t res = TinyMegaI2C.read();
        // 1. [NO NEED] Acknowledgement from Master.
        // 2. [NO NEED] The above Steps can be repeated if necessary and the address bit increments automatically.
        // 3. ** The Master, addressed as Receiver, can stop data transmission by not generating an acknowledge on the
        // last byte that has been sent from the Slave {thaat's why we didn't do step 1 here}.
        // In this event, the Slave-Transmitter must leave the data line HIGH to enable the Master to generate a STOP condition.
        TinyMegaI2C.stop();
        return (res);
      } else {
        return (false);
      }
    } else {
      return (false);
    }
  } else {
    return (false);
  }
}


bool RV8803Tiny::readMultipleRegisters(uint8_t addr, uint8_t * dest, uint8_t len) {
  //  i2cPort->beginTransmission(RV8803_ADDR);
  //  _i2cPort->write(addr);
  //  if (_i2cPort->endTransmission() != 0)
  //    return (false); //Error: Sensor did not ack
  //
  //  _i2cPort->requestFrom(static_cast<uint8_t>(RV8803_ADDR), len);
  //  for (uint8_t i = 0; i < len; i++){
  //    dest[i] = _i2cPort->read();
  //  }
  //  return (true);


  //  Master sends out the START condition, signifyig it'll be a write operation [ R/W bit is a 0 ]
  if (TinyMegaI2C.start(RV8803_ADDR, 0)) { //  if Acknowledged from RV-8803
    //  Master sends out the Register Address to RV-8803-C7.
    if (TinyMegaI2C.write(addr)) { //  if Acknowledged from RV-8803
      //  Master sends out the Repeated START condition (or STOP condition followed by START condition)
      //  Master sends out Slave Address, 65h for the RV-8803 [ R/W bit is -1 ] indicating unknown number of read operation
      if (TinyMegaI2C.restart(RV8803_ADDR, -1)) { //Acknowledgement from RV-8803-C7
        // The Slave sends out the Data from the Register Address
        // 1. [NO NEED] Acknowledgement from Master.
        // 2. [NO NEED] The above Steps can be repeated if necessary and the address bit increments automatically.
        // 3. ** The Master, addressed as Receiver, can stop data transmission by not generating an acknowledge on the
        // last byte that has been sent from the Slave {thaat's why we didn't do step 1 here}.
        // In this event, the Slave-Transmitter must leave the data line HIGH to enable the Master to generate a STOP condition.

        for (uint8_t i = 0; i < len; i++) {
          dest[i] = TinyMegaI2C.read();
        }
        
        TinyMegaI2C.stop();
        return (res);
      } else {
        return (false);
      }
    } else {
      return (false);
    }
  } else {
    return (false);
  }
}

Am I in the right direction. Some help would be really great here. Here is the datasheet of the RTC clock.

If we look at the dataSheet at points (6.8 & 6.9 - read operation methods), it's a bit confusing..

Best Datta