eMBErrorCode
eMBPoll( void )
{
static UCHAR *ucMBFrame;
static UCHAR ucRcvAddress;
static UCHAR ucFunctionCode;
static USHORT usLength;
static eMBException eException;
int i;
eMBErrorCode eStatus = MB_ENOERR;
eMBEventType eEvent;
/* Check if the protocol stack is ready. */
//HAL_UART_Transmit(&huart1, "C" , 1, 0xFFFF);
if( eMBState != STATE_ENABLED )
{
return MB_EILLSTATE;
}
/* Check if there is a event available. If not return control to caller.
* Otherwise we will handle the event. */
//HAL_UART_Transmit(&huart1, "A" , 1, 0xFFFF);
if( xMBPortEventGet( &eEvent ) == TRUE )
{
HAL_UART_Transmit(&huart1, "B" , 1, 0xFFFF);
switch ( eEvent )
{
case EV_READY:
break;
case EV_FRAME_RECEIVED:
HAL_UART_Transmit(&huart1, "F" , 1, 0xFFFF);
eStatus = peMBFrameReceiveCur( &ucRcvAddress, &ucMBFrame, &usLength );
if( eStatus == MB_ENOERR )
{
/* Check if the frame is for us. If not ignore the frame. */
if( ( ucRcvAddress == ucMBAddress ) || ( ucRcvAddress == MB_ADDRESS_BROADCAST ) )
{
( void )xMBPortEventPost( EV_EXECUTE );
}
}
break;
case EV_EXECUTE:
HAL_UART_Transmit(&huart1, "Ex\n\r" , 4, 0xFFFF);
ucFunctionCode = ucMBFrame[MB_PDU_FUNC_OFF];
HAL_UART_Transmit(&huart1, &ucFunctionCode , 1, 0xFFFF);
eException = MB_EX_ILLEGAL_FUNCTION;
for( i = 0; i < MB_FUNC_HANDLERS_MAX; i++ )
{
/* No more function handlers registered. Abort. */
if( xFuncHandlers[i].ucFunctionCode == 0 )
{
break;
}
else if( xFuncHandlers[i].ucFunctionCode == ucFunctionCode )
{
eException = xFuncHandlers[i].pxHandler( ucMBFrame, &usLength );
break;
}
}
/* If the request was not sent to the broadcast address we
* return a reply. */
if( ucRcvAddress != MB_ADDRESS_BROADCAST )
{
if( eException != MB_EX_NONE )
{
/* An exception occured. Build an error frame. */
usLength = 0;
ucMBFrame[usLength++] = ( UCHAR )( ucFunctionCode | MB_FUNC_ERROR );
ucMBFrame[usLength++] = eException;
}
if( ( eMBCurrentMode == MB_ASCII ) && MB_ASCII_TIMEOUT_WAIT_BEFORE_SEND_MS )
{
vMBPortTimersDelay( MB_ASCII_TIMEOUT_WAIT_BEFORE_SEND_MS );
}
eStatus = peMBFrameSendCur( ucMBAddress, ucMBFrame, usLength );
}
break;
case EV_FRAME_SENT:
break;
}
}
HAL_UART_Transmit(&huart1, "X" , 1, 0xFFFF);
return MB_ENOERR;
}
BOOL
xMBASCIITransmitFSM( void )
{
BOOL xNeedPoll = FALSE;
UCHAR ucByte;
assert( eRcvState == STATE_RX_IDLE );
switch ( eSndState )
{
/* Start of transmission. The start of a frame is defined by sending
* the character ':'. */
case STATE_TX_START:
ucByte = ':';
xMBPortSerialPutByte( ( CHAR )ucByte );
eSndState = STATE_TX_DATA;
eBytePos = BYTE_HIGH_NIBBLE;
break;
/* Send the data block. Each data byte is encoded as a character hex
* stream with the high nibble sent first and the low nibble sent
* last. If all data bytes are exhausted we send a '\r' character
* to end the transmission. */
case STATE_TX_DATA:
if( usSndBufferCount > 0 )
{
switch ( eBytePos )
{
case BYTE_HIGH_NIBBLE:
ucByte = prvucMBBIN2CHAR( ( UCHAR )( *pucSndBufferCur >> 4 ) );
xMBPortSerialPutByte( ( CHAR ) ucByte );
eBytePos = BYTE_LOW_NIBBLE;
break;
case BYTE_LOW_NIBBLE:
ucByte = prvucMBBIN2CHAR( ( UCHAR )( *pucSndBufferCur & 0x0F ) );
xMBPortSerialPutByte( ( CHAR )ucByte );
pucSndBufferCur++;
eBytePos = BYTE_HIGH_NIBBLE;
usSndBufferCount--;
break;
}
}
else
{
xMBPortSerialPutByte( MB_ASCII_DEFAULT_CR );
eSndState = STATE_TX_END;
}
break;
/* Finish the frame by sending a LF character. */
case STATE_TX_END:
xMBPortSerialPutByte( ( CHAR )ucMBLFCharacter );
/* We need another state to make sure that the CR character has
* been sent. */
eSndState = STATE_TX_NOTIFY;
break;
/* Notify the task which called eMBASCIISend that the frame has
* been sent. */
case STATE_TX_NOTIFY:
eSndState = STATE_TX_IDLE;
xNeedPoll = xMBPortEventPost( EV_FRAME_SENT );
/* Disable transmitter. This prevents another transmit buffer
* empty interrupt. */
vMBPortSerialEnable( TRUE, FALSE );
eSndState = STATE_TX_IDLE;
break;
/* We should not get a transmitter event if the transmitter is in
* idle state. */
case STATE_TX_IDLE:
/* enable receiver/disable transmitter. */
vMBPortSerialEnable( TRUE, FALSE );
break;
}
/*! \ingroup port_win32tcp
*
* \brief Pool the listening socket and currently connected Modbus TCP clients
* for new events.
* \internal
*
* This function checks if new clients want to connect or if already connected
* clients are sending requests. If a new client is connected and there are
* still client slots left (The current implementation supports only one)
* then the connection is accepted and an event object for the new client
* socket is activated (See prvbMBPortAcceptClient() ).
* Events for already existing clients in \c FD_READ and \c FD_CLOSE. In case of
* an \c FD_CLOSE the client connection is released (See prvvMBPortReleaseClient() ).
* In case of an \c FD_READ command the existing data is read from the client
* and if a complete frame has been received the Modbus Stack is notified.
*
* \return FALSE in case of an internal I/O error. For example if the internal
* event objects are in an invalid state. Note that this does not include any
* client errors. In all other cases returns TRUE.
*/
BOOL
xMBPortTCPPool( void )
{
int n;
fd_set fread;
struct timeval tval;
tval.tv_sec = 0;
tval.tv_usec = 5000;
int ret;
USHORT usLength;
if( xClientSocket == INVALID_SOCKET )
{
/* Accept to client */
if( ( n = select( xListenSocket + 1, &allset, NULL, NULL, NULL ) ) < 0 )
{
if( errno == EINTR )
{
;
}
else
{
;
}
}
if( FD_ISSET( xListenSocket, &allset ) )
{
( void )prvbMBPortAcceptClient( );
}
}
while( TRUE )
{
FD_ZERO( &fread );
FD_SET( xClientSocket, &fread );
if( ( ( ret = select( xClientSocket + 1, &fread, NULL, NULL, &tval ) ) == SOCKET_ERROR )
|| !ret )
{
continue;
}
if( ret > 0 )
{
if( FD_ISSET( xClientSocket, &fread ) )
{
if( ( ( ret =
recv( xClientSocket, &aucTCPBuf[usTCPBufPos], usTCPFrameBytesLeft,
0 ) ) == SOCKET_ERROR ) || ( !ret ) )
{
close( xClientSocket );
xClientSocket = INVALID_SOCKET;
return TRUE;
}
usTCPBufPos += ret;
usTCPFrameBytesLeft -= ret;
if( usTCPBufPos >= MB_TCP_FUNC )
{
/* Length is a byte count of Modbus PDU (function code + data) and the
* unit identifier. */
usLength = aucTCPBuf[MB_TCP_LEN] << 8U;
usLength |= aucTCPBuf[MB_TCP_LEN + 1];
/* Is the frame already complete. */
if( usTCPBufPos < ( MB_TCP_UID + usLength ) )
{
usTCPFrameBytesLeft = usLength + MB_TCP_UID - usTCPBufPos;
}
/* The frame is complete. */
else if( usTCPBufPos == ( MB_TCP_UID + usLength ) )
{
( void )xMBPortEventPost( EV_FRAME_RECEIVED );
return TRUE;
}
/* This can not happend because we always calculate the number of bytes
* to receive. */
else
{
assert( usTCPBufPos <= ( MB_TCP_UID + usLength ) );
}
}
}
}
}
return TRUE;
}
BOOL
xMBASCIIReceiveFSM( void )
{
BOOL xNeedPoll = FALSE;
UCHAR ucByte;
UCHAR ucResult;
assert( eSndState == STATE_TX_IDLE );
( void )xMBPortSerialGetByte( ( CHAR * ) & ucByte );
switch ( eRcvState )
{
/* A new character is received. If the character is a ':' the input
* buffer is cleared. A CR-character signals the end of the data
* block. Other characters are part of the data block and their
* ASCII value is converted back to a binary representation.
*/
case STATE_RX_RCV:
/* Enable timer for character timeout. */
vMBPortTimersEnable( );
if( ucByte == ':' )
{
/* Empty receive buffer. */
eBytePos = BYTE_HIGH_NIBBLE;
usRcvBufferPos = 0;
}
else if( ucByte == MB_ASCII_DEFAULT_CR )
{
eRcvState = STATE_RX_WAIT_EOF;
}
else
{
ucResult = prvucMBCHAR2BIN( ucByte );
switch ( eBytePos )
{
/* High nibble of the byte comes first. We check for
* a buffer overflow here. */
case BYTE_HIGH_NIBBLE:
if( usRcvBufferPos < MB_SER_PDU_SIZE_MAX )
{
ucASCIIBuf[usRcvBufferPos] = ( UCHAR )( ucResult << 4 );
eBytePos = BYTE_LOW_NIBBLE;
break;
}
else
{
/* not handled in Modbus specification but seems
* a resonable implementation. */
eRcvState = STATE_RX_IDLE;
/* Disable previously activated timer because of error state. */
vMBPortTimersDisable( );
}
break;
case BYTE_LOW_NIBBLE:
ucASCIIBuf[usRcvBufferPos++] |= ucResult;
eBytePos = BYTE_HIGH_NIBBLE;
break;
}
}
break;
case STATE_RX_WAIT_EOF:
if( ucByte == ucMBLFCharacter )
{
/* Disable character timeout timer because all characters are
* received. */
vMBPortTimersDisable( );
/* Receiver is again in idle state. */
eRcvState = STATE_RX_IDLE;
/* Notify the caller of eMBASCIIReceive that a new frame
* was received. */
xNeedPoll = xMBPortEventPost( EV_FRAME_RECEIVED );
}
else if( ucByte == ':' )
{
/* Empty receive buffer and back to receive state. */
eBytePos = BYTE_HIGH_NIBBLE;
usRcvBufferPos = 0;
eRcvState = STATE_RX_RCV;
/* Enable timer for character timeout. */
vMBPortTimersEnable( );
}
else
{
/* Frame is not okay. Delete entire frame. */
eRcvState = STATE_RX_IDLE;
}
break;
case STATE_RX_IDLE:
if( ucByte == ':' )
{
/* Enable timer for character timeout. */
vMBPortTimersEnable( );
/* Reset the input buffers to store the frame. */
usRcvBufferPos = 0;;
eBytePos = BYTE_HIGH_NIBBLE;
eRcvState = STATE_RX_RCV;
}
break;
}
return xNeedPoll;
}
