twi.h.svn-base

AVR单片机下

/*                ****ROBOCON 2009 | BUPT TEAM*******
 * ------------------------------------------------------------------------
 * FileName   : twi.h
 * Version    : 2.0
 * Brief      :
 * Code by    : leaf
 * Date       : Apr 28, 2009
 * Note       :
 *
 *
 * ------------------------------------------------------------------------
 */

#ifndef TWI_H_INCLUDED
#define TWI_H_INCLUDED

#include <util/twi.h>

#ifndef F_CPU
/* prevent compiler error by supplying a default */
# warning "F_CPU not defined for <lib_bupt/usart.h>"
# define F_CPU 14745600UL
#endif
#define TWBR_FROM_FREQ( f ) ( (F_CPU/(f) - 16 + 1<<( (UINT16)(TWSR&0x03) << 1 )) / 1 )

/* (mode & TWI_TR_MASK) 0-T, 1-R */
#define TWI_TR_MASK 0x01
/* (mode & TWI_MS_MASK) 0-M, 1-S */
#define TWI_MS_MASK 0x02
typedef enum{
	TwiModeStop = 0,
	TwiModeST   = 2,
	TwiModeSR   = 3,
	TwiModeMT   = 4,
	TwiModeMR   = 5
}TwiMode;
typedef enum{
	TwiErrOpen  = -1,
	TwiErrStart = -2,
	TwiErrSla   = -3,
	TwiErrMatch = -4,
	TwiErrOther = -6
}TwiErrState;

typedef UINT8 TwiAddr;

/* 初始化设备，指定波特率（分频为00） */
void twiInit( UINT8 baud );
int  twiOpen( TwiAddr adr, TwiMode mode );
int  twiWrite( const void *data, size_t sz );
int  twiRead( void *buf, size_t sz);
int  twiClose( void );

#endif