www.pudn.com > DeviceNet.zip > EMM.c, change:2003-09-19,size:5089b


/***************************************************************************** 
 * 
 * Microchip DeviceNet Stack (Explicit Messaging Manager Source) 
 * 
 ***************************************************************************** 
 * FileName:        emm.c 
 * Dependencies:     
 * Processor:       PIC18F with CAN 
 * Compiler:       	C18 02.20.00 or higher 
 * Linker:          MPLINK 03.40.00 or higher 
 * Company:         Microchip Technology Incorporated 
 * 
 * Software License Agreement 
 * 
 * The software supplied herewith by Microchip Technology Incorporated 
 * (the "Company") is intended and supplied to you, the Company's 
 * customer, for use solely and exclusively with products manufactured 
 * by the Company.  
 * 
 * The software is owned by the Company and/or its supplier, and is  
 * protected under applicable copyright laws. All rights are reserved.  
 * Any use in violation of the foregoing restrictions may subject the  
 * user to criminal sanctions under applicable laws, as well as to  
 * civil liability for the breach of the terms and conditions of this  
 * license. 
 * 
 * THIS SOFTWARE IS PROVIDED IN AN "AS IS" CONDITION. NO WARRANTIES,  
 * WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED  
 * TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A  
 * PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. THE COMPANY SHALL NOT,  
 * IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL OR  
 * CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER. 
 * 
 * 
 * This file is simply a managing routine that parses data from the  
 * Explicit Messaging Connection for the router. 
 * 
 * Author               Date        Comment 
 *~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 
 * Ross Fosler			05/03/03	...	 
 *  
 *****************************************************************************/ 
 
 
 
 
#include	"dnet.def"				// Global definitions file 
#include 	"typedefs.h" 
 
#include	"route.h"				// Router prototypes and macros 
 
#include	"services.h"			// Service codes 
#include	"errors.h"				// Error codes 
#include	"class.h"				// Class codes 
 
#include 	"conn.h"				// Connection object 
#include	"dnet.h"				// DeviceNet object 
 
 
#define	_HDR_SIZE 		sizeof(route.header)   
#define _CID_SIZE		sizeof(route.classID) 
#define	_IID_SIZE		sizeof(route.instanceID) 
#define	_SVC_SIZE		sizeof(route.service) 
#define	_HSCI_SIZE		_HDR_SIZE + _SVC_SIZE +	_CID_SIZE +	_IID_SIZE 
 
 
 
 
/********************************************************************* 
 * Function:        unsigned char ExplicitMsgManager(void) 
 * 
 * PreCondition:     
 * 
 * Input:       	none		 
 *                   
 * Output:      	status of the process	 
 * 
 * Side Effects:    none 
 * 
 * Overview:        This function manages any Explicit Message data 
 *					and provides parsing for the Router. 
 * 
 * Note:            
 ********************************************************************/ 
unsigned char ExplicitMsgManager(void) 
{ 
	USINT retStatus; 
 
	retStatus = 0; 
 
	// Do only if the connection object is prepared to receive and transmit 
	if (_ConnReadRdy(1) && _ConnWriteRdy(1)) 
	{ 
		// Insure that sufficient data has been received to process 
		if (uConn1.rx.len >= (_HSCI_SIZE)) 
		{	 
			// Set the buffer pointers and other info based on the connection object settings 
			route.pInBuf = uConn1RxBuffer;   
			route.pOutBuf = uConn1TxBuffer + (_HDR_SIZE + _SVC_SIZE); 
			route.inBufLen = uConn1.rx.lenMax - (_HSCI_SIZE); 
			route.inBufDataLen = uConn1.rx.len - (_HSCI_SIZE); 
			route.outBufLen = uConn1.tx.lenMax - (_HDR_SIZE + _SVC_SIZE); 
			route.outBufDataLen = 0; 
 
 
			// Parse the buffer using pointers provided from the connection object 
			route.header = *route.pInBuf; route.pInBuf++;  
			route.service = *route.pInBuf; route.pInBuf++; 
			#if (CLASS_WIDTH_16BIT)  
			route.classID.bytes.LSB = *route.pInBuf; route.pInBuf++; 
			route.classID.bytes.MSB = *route.pInBuf; route.pInBuf++;  
			#else 
			route.classID = *route.pInBuf; route.pInBuf++; 
			#endif 
			#if (INSTANCE_WIDTH_16BIT) 
			route.instanceID.bytes.LSB = *route.pInBuf; route.pInBuf++; 
			route.instanceID.bytes.MSB = *route.pInBuf; route.pInBuf++;  
			#else 
			route.instanceID = *route.pInBuf; route.pInBuf++; 
			#endif 
			route.attributeID = *route.pInBuf; 
		    
			// Route the message to the object 
			retStatus = RouteMessage();		 
			 
			// Write the transmit buffer header and service info 
			// all other data should be provided by the appropriate class 
			uConn1.tx.len = route.outBufDataLen + (_HDR_SIZE + _SVC_SIZE); 
			if(uConn1.tx.len > 8) route.header |= 0x80; 
			else route.header &= 0x7F; 
			route.pOutBuf = uConn1TxBuffer; 
			*route.pOutBuf = route.header; route.pOutBuf++; 
			*route.pOutBuf = route.service | 0x80;		// Set the response bit 
								 
			_ConnRead(1);					// Unlock the read for explicit messaging 
			 
			if (retStatus) _ConnWrite(1);	// Enable write for explicit messaging 
		} 
		else 
			return (retStatus); 
	} 
	else  
		return (0); 
}