data_receive.c

瑞萨CAN通讯单片机程序

/*""FILE COMMENT""*****************************************************
 *	M32R C Programming		Rev. 1.00
 *		 < Sample Program for CAN data_receive >
 *
 *	Copyright (c) 2003 Renesas Technology Corporation
 *			   And Renesas Solutions Corporation
 *			   All Rights Reserved
 *********************************************************************/

/************************************************************************/
/*		Include file						*/
/************************************************************************/

#include		"..\inc\sfr32170_pragma.h"

/************************************************************************/
/*		Function prototype declaration				*/
/************************************************************************/

	void		main(void);
	void		data_receive(void);
	void		read_data(void);
extern	void		can_init(void);

/************************************************************************/
/*		Externally referenced variable				*/
/************************************************************************/

	char		CAN_DATA[8];

/*""FUNC COMMENT""*******************************************************
 * Function name: void main(void)
 *-----------------------------------------------------------------------
 * Description	: Data frame transmission sample program
 *-----------------------------------------------------------------------
 * Argument	: -
 *-----------------------------------------------------------------------
 * Returns	: -
 *-----------------------------------------------------------------------
 * Notes	: -
 *""FUNC COMMENT END""***************************************************/
void main(void)
{
	/* Initializing CAN module */
	can_init();

	/* CAN module operation */
	data_receive();

	/* Wait until data is received in slot 0 */
	while( ( CAN0SLIST & SSB0) == 0x0000 )
		;

	/* Read out received data */
	read_data();

	/* End of program */
	while( 1 )
		;
}

/*""FUNC COMMENT""*******************************************************
 * Function name: void data_receive(void)
 *-----------------------------------------------------------------------
 * Description	: Receives data frame in slot 0
 *-----------------------------------------------------------------------
 * Argument	: -
 *-----------------------------------------------------------------------
 * Returns	: -
 *-----------------------------------------------------------------------
 * Notes	: -
 *""FUNC COMMENT END""***************************************************/
void data_receive(void)
{
	C0MSL0CNT = 0x00;				/* Initialize CAN message slot control register */
	while ( ( C0MSL0CNT & TRSTAT) != 0)		/* Verify that transmit operation is idle */
	;

	/* Set ID in message slot 0 */
	C0MSL0SID0 = 0x00;				/* ID : 0 */
	C0MSL0SID1 = 0x00;

	/* Set extended ID register */
	CAN0EXTID = 0x0000;				/* Select standard format */

	/* Set CAN message slot control register */
	C0MSL0CNT = 0x40;				/* Request reception of data frame */

	/*
	 * Because ID mask register is set within can_init() for "all bits to be checked,"
	 * slot 0 receives only data frames in standard format with ID:0.
	 */
}

/*""FUNC COMMENT""*******************************************************
 * Function name: void data_send(void)
 *-----------------------------------------------------------------------
 * Description	: Transmits data frame from slot 0
 *-----------------------------------------------------------------------
 * Argument	: -
 *-----------------------------------------------------------------------
 * Returns	: -
 *-----------------------------------------------------------------------
 * Notes	: -
 *""FUNC COMMENT END""***************************************************/
void read_data(void)
{
	do {
		C0MSL0CNT = 0x4E;			/* Clear TRFIN bit */

		/* Read out message slot 0 */
		CAN_DATA[0] = C0MSL0DT0;
		CAN_DATA[1] = C0MSL0DT1;
		CAN_DATA[2] = C0MSL0DT2;
		CAN_DATA[3] = C0MSL0DT3;
		CAN_DATA[4] = C0MSL0DT4;
		CAN_DATA[5] = C0MSL0DT5;
		CAN_DATA[6] = C0MSL0DT6;
		CAN_DATA[7] = C0MSL0DT7;

	} while( ( C0MSL0CNT & TRFIN) != 0 );		/* Redo if TRFIN bit is set */

	/* If necessary, check ML bit to see if message is lost
	 *
	 * if( (*C0MSL0CNT & ML) != 0)
	 *	(Processing for messages lost);
	 */
}