//
// Originally, 'endTransmission' was an f(void) function.
// It has been modified to take one parameter indicating
// whether or not a STOP should be performed on the bus.
// Calling endTransmission(false) allows a sketch to
// perform a repeated start.
//
// WARNING: Nothing in the library keeps track of whether
// the bus tenure has been properly ended with a STOP. It
// is very possible to leave the bus in a hung state if
// no call to endTransmission(true) is made. Some I2C
// devices will behave oddly if they do not see a STOP.
//
uint8_t TwoWire::endTransmission(uint8_t sendStop) {
uint8_t error = 0;
// transmit buffer (blocking)
TWI_StartWrite(twi, txAddress, 0, 0, txBuffer[0]);
if (!TWI_WaitByteSent(twi, XMIT_TIMEOUT))
error = 2; // error, got NACK on address transmit
if (error == 0) {
uint16_t sent = 1;
while (sent < txBufferLength) {
TWI_WriteByte(twi, txBuffer[sent++]);
if (!TWI_WaitByteSent(twi, XMIT_TIMEOUT))
error = 3; // error, got NACK during data transmmit
}
}
if (error == 0) {
TWI_Stop(twi);
if (!TWI_WaitTransferComplete(twi, XMIT_TIMEOUT))
error = 4; // error, finishing up
}
txBufferLength = 0; // empty buffer
status = MASTER_IDLE;
return error;
}
uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity, uint32_t iaddress, uint8_t isize, uint8_t sendStop) {
if (quantity > BUFFER_LENGTH)
quantity = BUFFER_LENGTH;
// perform blocking read into buffer
int readed = 0;
TWI_StartRead(twi, address, iaddress, isize);
do {
// Stop condition must be set during the reception of last byte
if (readed + 1 == quantity)
TWI_SendSTOPCondition( twi);
if (TWI_WaitByteReceived(twi, RECV_TIMEOUT))
rxBuffer[readed++] = TWI_ReadByte(twi);
else
break;
} while (readed < quantity);
TWI_WaitTransferComplete(twi, RECV_TIMEOUT);
// set rx buffer iterator vars
rxBufferIndex = 0;
rxBufferLength = readed;
return readed;
}
uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity) {
if (quantity > BUFFER_LENGTH)
{
quantity = BUFFER_LENGTH;
}
// perform blocking read into buffer
int readed = 0;
TWI_StartRead(twi, address, 0, 0);
do {
// Stop condition must be set during the reception of last byte
if (readed + 1 == quantity)
{
TWI_SendSTOPCondition( twi);
}
TWI_WaitByteReceived(twi, RECV_TIMEOUT);
rxBuffer[readed++] = twi_read_byte(twi);
} while (readed < quantity);
TWI_WaitTransferComplete(twi, RECV_TIMEOUT);
// set rx buffer iterator vars
rxBufferIndex = 0;
rxBufferLength = readed;
return readed;
}
//
// Originally, 'endTransmission' was an f(void) function.
// It has been modified to take one parameter indicating
// whether or not a STOP should be performed on the bus.
// Calling endTransmission(false) allows a sketch to
// perform a repeated start.
//
// WARNING: Nothing in the library keeps track of whether
// the bus tenure has been properly ended with a STOP. It
// is very possible to leave the bus in a hung state if
// no call to endTransmission(true) is made. Some I2C
// devices will behave oddly if they do not see a STOP.
//
uint8_t TwoWire::endTransmission(uint8_t sendStop) {
// transmit buffer (blocking)
TWI_StartWrite(twi, txAddress, 0, 0, txBuffer[0]);
TWI_WaitByteSent(twi, XMIT_TIMEOUT);
int sent = 1;
while (sent < txBufferLength) {
twi_write_byte(twi, txBuffer[sent++]);
TWI_WaitByteSent(twi, XMIT_TIMEOUT);
}
TWI_Stop( twi);
TWI_WaitTransferComplete(twi, XMIT_TIMEOUT);
// empty buffer
txBufferLength = 0;
status = MASTER_IDLE;
return sent;
}
