dsPIC33 EVM - I2C 테스트

dsPIC33 EVM - I2C 테스트

dspic33_i2c.pdf

dsPIC33 EVM  보드의 I2C는 RG2(SCL), RG3(SDA)에 연결되어 있다.

dsPIC33 I2C 초기화 코드

void i2c_init(unsigned int Speed)

{

OpenI2C1( I2C_ON, I2C_BRG );

}

dsPIC33 I2C Read/Write 소스 코드

unsigned char i2c_read_byte(unsigned char Addr, unsigned char reg)
{	
	unsigned char data = 0;	
	unsigned char SlaveAddress = Addr;
	char i2cData[10];
	int DataSz;
	int Index = 0;
	i2cData[0] = (SlaveAddress << 1) | 0;
	i2cData[1] = reg;	
	DataSz = 2;
	StartI2C1();
	IdleI2C1();
	while( DataSz )
	{
		MasterWriteI2C1( i2cData[Index++] );
		IdleI2C1();	
		DataSz--;
		if( I2C1STATbits.ACKSTAT )
			break;
	}
	RestartI2C1();
	i2c_wait(10);
	
	IdleI2C1();	
	MasterWriteI2C1( (SlaveAddress << 1) | 1 );
	IdleI2C1();
	data = MasterReadI2C1();
	
	StopI2C1();	
	IdleI2C1();	
	return data;
}
void i2c_write_byte(unsigned char Addr, unsigned char reg, unsigned char data)
{
	unsigned char SlaveAddress = Addr;
	char i2cData[10];
	int DataSz;
	int Index = 0;
	char status;
	i2cData[0] = (SlaveAddress << 1) | 0;
	i2cData[1] = reg;
	i2cData[2] = data;
	DataSz = 3;
	StartI2C1();
	IdleI2C1();	
	while( DataSz )
	{
		MasterWriteI2C1( i2cData[Index++] );
		IdleI2C1();		
		DataSz--;
		if( I2C1STATbits.ACKSTAT )
			break;
	}
	StopI2C1();
	IdleI2C1();
}

dsPIC33 EVM을 이용한 I2C 온습도 센서 테스트 예제