PCA9554.cpp

#include <PCA9554.h>

PCA9554::PCA9554(byte SlaveAddress)
{
	_SlaveAddress = SlaveAddress;
}


bool PCA9554::twiRead(byte &registerAddress)
{
	Wire.beginTransmission(_SlaveAddress);
  	Wire.write(registerAddress);

  	if(Wire.endTransmission() == 0)
  	{
    		delay(15);
    		Wire.requestFrom(_SlaveAddress, 1, true);
    		while(Wire.available() < 1);
    		registerAddress = Wire.read();
    		return true;
  	}
  	return false;
}

bool PCA9554::twiWrite(byte registerAddress, byte dataWrite)
{
	Wire.beginTransmission(_SlaveAddress);
  	Wire.write(registerAddress);
  	Wire.write(dataWrite);

  	if(Wire.endTransmission() == 0)
    		return true;
  	return false;
}

bool PCA9554::pinMode(byte pinNumber, bool state)
{
	byte oldValue = CONFIGPORT;
	if(this->twiRead(oldValue) && (pinNumber <= 7))
	{
		if(!state)
		{
			oldValue |= (1 << pinNumber);
			if(this->portMode(oldValue))
				return true;
			return false;
		}
		else if(state)
		{
			oldValue &= ~(1 << pinNumber);
			if(this->portMode(oldValue))
				return true;
			return false;
		}
	}
	return false;
}

bool PCA9554::portMode(byte value)
{
	if(this->twiWrite(CONFIGPORT, value))
		return true;
	return false;
}


bool PCA9554::digitalWrite(byte pinNumber, bool state)
{
	byte oldValue = OUTPUTPORT;
	if(this->twiRead(oldValue) && pinNumber <= 7)
	{
		if(state)
		{
			oldValue |= (1 << pinNumber);
			if(this->digitalWritePort(oldValue))
				return true;
			return false;
		}
		else if(!state)
		{
			oldValue &= ~(1 << pinNumber);
			if(this->digitalWritePort(oldValue))
				return true;
			return false;
		}
	}
	return false;
}



bool PCA9554::digitalWritePort(byte value)
{
	if(this->twiWrite(OUTPUTPORT, value))
		return true;
	return false;
}



bool PCA9554::digitalRead(byte &pinNumber)
{
	byte oldValue = INPUTPORT;
	if(this->twiRead(oldValue) && (pinNumber <= 7))
	{
		oldValue &= (1 << pinNumber);
		if(oldValue > 0) pinNumber = 1;
		else pinNumber = 0;
		return true;
	}
	return false;
}


bool PCA9554::digitalReadPort(byte &value)
{
	value = INPUTPORT;
	if(this->twiRead(value))
		return true;
	return false;
}