const char*
WiFlyDevice::ip()
{
/*
The return value is intended to be dropped directly
into calls to 'print' or 'println' style methods.
*/
static char ip[IP_ADDRESS_BUFFER_SIZE] = "";
// TODO: Ensure we're not in a connection?
_enter_command_mode();
// Version 2.19 of the WiFly firmware has a "get ip a" command but
// we can't use it because we want to work with 2.18 too.
_send_command( F( "get ip" ), false, "IP=" );
char newChar;
byte offset = 0;
// Copy the IP address from the response into our buffer
while( offset < IP_ADDRESS_BUFFER_SIZE )
{
newChar = _uart->read();
if( newChar == ':' )
{
ip[offset] = '\x00';
break;
}
else if( newChar != -1 )
{
ip[offset] = newChar;
offset++;
}
}
// This handles the case when we reach the end of the buffer
// in the loop. (Which should never happen anyway.)
// And hopefully this prevents us from failing completely if
// there's a mistake above.
ip[IP_ADDRESS_BUFFER_SIZE-1] = '\x00';
// This should skip the remainder of the output.
// TODO: Handle this better?
_wait_for_response( "<" );
while (_uart->read() != ' '); // Skip the prompt.
// For some reason the "sendCommand" approach leaves the system
// in a state where it misses the first/next connection so for
// now we don't check the response.
// TODO: Fix this
_uart->println( "exit" );
//_send_command("exit", false, "EXIT");
return ip;
}
static int _start(SercomI2cm *dev, uint16_t addr)
{
/* Wait for hardware module to sync */
DEBUG("Wait for device to be ready\n");
while (dev->SYNCBUSY.reg & SERCOM_I2CM_SYNCBUSY_MASK) {}
/* Set action to ACK. */
dev->CTRLB.reg &= ~SERCOM_I2CM_CTRLB_ACKACT;
/* Send Start | Address | Write/Read */
DEBUG("Generate start condition by sending address\n");
dev->ADDR.reg = (addr) | (0 << SERCOM_I2CM_ADDR_HS_Pos);
/* Wait for response on bus. */
if (addr & I2C_READ) {
/* Some devices (e.g. SHT2x) can hold the bus while
preparing the reply */
if (_wait_for_response(dev, 100 * SAMD21_I2C_TIMEOUT) < 0)
return -ETIMEDOUT;
}
else {
if (_wait_for_response(dev, SAMD21_I2C_TIMEOUT) < 0)
return -ETIMEDOUT;
}
/* Check for address response error unless previous error is detected. */
/* Check for error and ignore bus-error; workaround for BUSSTATE
* stuck in BUSY */
if (dev->INTFLAG.reg & SERCOM_I2CM_INTFLAG_SB) {
/* Clear write interrupt flag */
dev->INTFLAG.reg = SERCOM_I2CM_INTFLAG_SB;
/* Check arbitration. */
if (dev->STATUS.reg & SERCOM_I2CM_STATUS_ARBLOST) {
DEBUG("STATUS_ERR_PACKET_COLLISION\n");
return -EAGAIN;
}
}
/* Check that slave responded with ack. */
else if (dev->STATUS.reg & SERCOM_I2CM_STATUS_RXNACK) {
/* Slave busy. Issue ack and stop command. */
dev->CTRLB.reg |= SERCOM_I2CM_CTRLB_CMD(3);
DEBUG("STATUS_ERR_BAD_ADDRESS\n");
return -ENXIO;
}
return 0;
}
static inline int _read(SercomI2cm *dev, uint8_t *data, int length,
uint8_t stop)
{
uint8_t count = 0;
/* Set action to ack. */
dev->CTRLB.reg &= ~SERCOM_I2CM_CTRLB_ACKACT;
/* Read data buffer. */
while (length--) {
/* Check that bus ownership is not lost. */
if ((dev->STATUS.reg & SERCOM_I2CM_STATUS_BUSSTATE_Msk)
!= BUSSTATE_OWNER) {
DEBUG("STATUS_ERR_PACKET_COLLISION\n");
return -EAGAIN;
}
/* Wait for hardware module to sync */
while (dev->SYNCBUSY.reg & SERCOM_I2CM_SYNCBUSY_MASK) {}
/* Check if this is the last byte to read */
if (length == 0 && stop) {
/* Send NACK before STOP */
dev->CTRLB.reg |= SERCOM_I2CM_CTRLB_ACKACT;
/* Prepare stop command before read last byte otherwise
hardware will request an extra byte to read */
_stop(dev);
}
/* Save data to buffer. */
data[count] = dev->DATA.reg;
/* Wait for response on bus. */
if (length > 0) {
if (_wait_for_response(dev, SAMD21_I2C_TIMEOUT) < 0)
return -ETIMEDOUT;
}
count++;
}
return 0;
}
static inline int _write(SercomI2cm *dev, const uint8_t *data, int length,
uint8_t stop)
{
uint8_t count = 0;
/* Write data buffer until the end. */
DEBUG("Looping through bytes\n");
while (length--) {
/* Check that bus ownership is not lost. */
if ((dev->STATUS.reg & SERCOM_I2CM_STATUS_BUSSTATE_Msk)
!= BUSSTATE_OWNER) {
DEBUG("STATUS_ERR_PACKET_COLLISION\n");
return -EAGAIN;
}
/* Wait for hardware module to sync */
while (dev->SYNCBUSY.reg & SERCOM_I2CM_SYNCBUSY_MASK) {}
DEBUG("Written byte #%i to data reg, now waiting for DR"
" to be empty again\n", count);
dev->DATA.reg = data[count++];
/* Wait for response on bus. */
if (_wait_for_response(dev, SAMD21_I2C_TIMEOUT) < 0) {
return -ETIMEDOUT;
}
/* Check for NACK from slave. */
if (dev->STATUS.reg & SERCOM_I2CM_STATUS_RXNACK) {
DEBUG("STATUS_ERR_OVERFLOW\n");
return -EIO;
}
}
if (stop) {
/* Issue stop command */
_stop(dev);
}
return 0;
}
