char MOD_IO2::WriteSingle( char data )
{
char i;
// Send the 8 bits
for(i = 0; i<8; i++)
{
WaitMicrosecond(1000);
if(data&RW_MASK)
SDA_IN();
else
SDA_OUT();
data <<= 1;
WaitMicrosecond(1000);
SCL_IN();
WaitMicrosecond(1000);
SCL_OUT();
}
// Read the ACK
WaitMicrosecond(1000);
SDA_IN();
WaitMicrosecond(1000);
SCL_IN();
WaitMicrosecond(1000);
i = digitalRead(pinSDA);
SCL_OUT();
WaitMicrosecond(1000);
return i;
}
char MOD_IO2::ReadSingle( char ack )
{
char data = 0, i;
SDA_IN();
for(i = 0; i < 8; i++)
{
WaitMicrosecond(1000);
SCL_IN();
while(digitalRead(pinSCL)==0);
WaitMicrosecond(1000);
data |= digitalRead(pinSDA);
if( i!=7 )
data<<=1;
WaitMicrosecond(1000);
SCL_OUT();
WaitMicrosecond(1000);
}
// send the ACK/NACK
WaitMicrosecond(1000);
if(ack)
SDA_IN();
else
SDA_OUT();
WaitMicrosecond(1000);
SCL_IN();
WaitMicrosecond(1000);
SCL_OUT();
WaitMicrosecond(1000);
return data;
}
byte MP3Player::i2c_rx(byte ack)
{
byte x, d=0;
SDA_H();
for(x=0; x<8; x++)
{
d <<= 1;
do {
SCL_H();
}
while(SCL_IN()==0); // wait for any SCL clock stretching
i2c_dly();
if(SDA_IN()) d |= 1;
SCL_L();
}
if(ack)
{
SDA_L();
}
else
{
SDA_H();
}
SCL_H()
i2c_dly(); // send (N)ACK bit
SCL_L();
SDA_H();
return d;
}
void MOD_IO2::Stop()
{
SDA_OUT();
WaitMicrosecond(1000);
SCL_IN();
WaitMicrosecond(1000);
SDA_IN();
WaitMicrosecond(1000);
}
unsigned char read_SCL(void) // Set SCL as input and return current level of line, 0 or 1
{
SCL_IN();
return !!SCL();
}
void i2cInit(void) {
SDA_IN();
SCL_IN();
}