//*****************************************************************************
//! Handles the UART interrupt.
//!
//! \param ucPort is the serial port number to be accessed.
//!
//! This function is called when either of the UARTs generate an interrupt.
//! An interrupt will be generated when data is received and when the transmit
//! FIFO becomes half empty. The transmit and receive FIFOs are processed as
//! appropriate.
//!
//! \return None.
//*****************************************************************************
static void SerialUARTIntHandler(uint8_t ucPort)
{
// Get the cause of the interrupt.
uint32_t ulStatus = UARTIntStatus(g_ulUARTBase[ucPort], true);
// Clear the cause of the interrupt.
UARTIntClear(g_ulUARTBase[ucPort], ulStatus);
// See if there is data to be processed in the receive FIFO.
if(ulStatus & (UART_INT_RT | UART_INT_RX))
{
// Loop while there are characters available in the receive FIFO.
while(UARTCharsAvail(g_ulUARTBase[ucPort]))
{
// Get the next character from the receive FIFO.
uint8_t ucChar = UARTCharGet(g_ulUARTBase[ucPort]);
#ifdef PROTOCOL_TELNET
// If Telnet protocol enabled, check for incoming IAC character,
// and escape it.
if((g_sParameters.sPort[ucPort].ucFlags &
PORT_FLAG_PROTOCOL) == PORT_PROTOCOL_TELNET)
{
// If this is a Telnet IAC character, write it twice.
if((ucChar == TELNET_IAC) &&
(RingBufFree(&g_sRxBuf[ucPort]) >= 2))
{
RingBufWriteOne(&g_sRxBuf[ucPort], ucChar);
RingBufWriteOne(&g_sRxBuf[ucPort], ucChar);
}
// If not a Telnet IAC character, only write it once.
else if((ucChar != TELNET_IAC) &&
(RingBufFree(&g_sRxBuf[ucPort]) >= 1))
{
RingBufWriteOne(&g_sRxBuf[ucPort], ucChar);
}
}
// if not Telnet, then only write the data once.
else
#endif
{
if (fDataDebugFlag)
CONSOLE("%u: from UART %02X\n", ucPort, ucChar);
if (IsModemModeCommand(ucPort))
ProcessModemModeCommand(ucPort, ucChar);
else
{
ProcessModemModeData(ucPort, ucChar);
RingBufWriteOne(&g_sRxBuf[ucPort], ucChar);
}
ProcessModemToServerData(ucPort);
ProcessServerToModemData(ucPort, ucChar);
}
}
}
#ifdef SERIAL_FLOW_CONTROL
// If flow control is enabled, check the status of the RX buffer to
// determine if flow control GPIO needs to be asserted.
if(g_sParameters.sPort[ucPort].ucFlowControl == SERIAL_FLOW_CONTROL_HW)
{
// If the ring buffer is down to less than 25% free, assert the
// outbound flow control pin.
if(RingBufFree(&g_sRxBuf[ucPort]) <
(RingBufSize(&g_sRxBuf[ucPort]) / 4))
{
GPIOPinWrite(g_ulFlowOutBase[ucPort], g_ulFlowOutPin[ucPort],
g_ulFlowOutPin[ucPort]);
}
}
#endif
// See if there is space to be filled in the transmit FIFO.
if(((ulStatus & UART_INT_TX) != 0) || (ulStatus == 0))
{
bool fInMode = true;
// Loop while there is space in the transmit FIFO and characters to be sent.
while(!RingBufEmpty(&g_sTxBuf[ucPort]) && UARTSpaceAvail(g_ulUARTBase[ucPort]))
{
uint8_t ucChar = RingBufReadOne(&g_sTxBuf[ucPort]);
if (fDataDebugFlag)
CONSOLE("%u: to UART %02X\n", ucPort, ucChar);
// Write the next character into the transmit FIFO.
UARTCharPut(g_ulUARTBase[ucPort], ucChar);
CustomerSettings1_SerialProcessCharacter(ucPort, ucChar);
mcwUARTTxOut[ucPort]--;
fInMode = false;
}
if((ulStatus & UART_INT_TX) != 0)
{
if ((mcwUARTTxOut[ucPort] == 0) && (fInMode)) {
InMode(ucPort);
}
}
}
}
//*****************************************************************************
//
//! Add bytes to the ring buffer by advancing the write index.
//!
//! \param ptRingBuf points to the ring buffer to which bytes have been added.
//! \param ulNumBytes is the number of bytes added to the buffer.
//!
//! This function should be used by clients who wish to add data to the buffer
//! directly rather than via calls to RingBufWrite() or RingBufWriteOne(). It
//! advances the write index by a given number of bytes. If the \e ulNumBytes
//! parameter is larger than the amount of free space in the buffer, the
//! read pointer will be advanced to cater for the addition. Note that this
//! will result in some of the oldest data in the buffer being discarded.
//!
//! \return None.
//
//*****************************************************************************
void
RingBufAdvanceWrite(tRingBufObject *ptRingBuf,
unsigned long ulNumBytes)
{
unsigned long ulCount;
tBoolean bIntsOff;
//
// Check the arguments.
//
ASSERT(ptRingBuf != NULL);
//
// Make sure we were not asked to add a silly number of bytes.
//
ASSERT(ulNumBytes <= ptRingBuf->ulSize);
//
// Determine how much free space we currently think the buffer has.
//
ulCount = RingBufFree(ptRingBuf);
//
// Advance the buffer write index by the required number of bytes and
// check that we have not run past the read index. Note that we must do
// this within a critical section (interrupts disabled) to prevent
// race conditions that could corrupt one or other of the indices.
//
bIntsOff = IntMasterDisable();
//
// Update the write pointer.
//
ptRingBuf->ulWriteIndex += ulNumBytes;
//
// Check and correct for wrap.
//
if(ptRingBuf->ulWriteIndex >= ptRingBuf->ulSize)
{
ptRingBuf->ulWriteIndex -= ptRingBuf->ulSize;
}
//
// Did the client add more bytes than the buffer had free space for?
//
if(ulCount < ulNumBytes)
{
//
// Yes - we need to advance the read pointer to ahead of the write
// pointer to discard some of the oldest data.
//
ptRingBuf->ulReadIndex = ptRingBuf->ulWriteIndex + 1;
//
// Correct for buffer wrap if necessary.
//
if(ptRingBuf->ulReadIndex >= ptRingBuf->ulSize)
{
ptRingBuf->ulReadIndex -= ptRingBuf->ulSize;
}
}
//
// Restore interrupts if we turned them off earlier.
//
if(!bIntsOff)
{
IntMasterEnable();
}
}
