i2c.h

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#ifndef	_I2C_H_
#define _I2C_H_

/*
 *	SDA (data) and SCL (clock) bits
 */

#define	SCL		RB7		/* clock on port B bit 7 */
#define	SCL_DIR		TRISB7

#define	SDA		RA1		/* data on port A bit 1 */
#define	SDA_DIR		TRISA1

#define I2C_INPUT	1		/* data direction input */
#define I2C_OUTPUT	0		/* data direction output */

#define I2C_READ	0x01		/* read bit used with address */
#define I2C_WRITE	0x00		/* write bit used with address */

#define FALSE		0
#define TRUE		!FALSE

#define I2C_ERROR	(-1)
#define I2C_LAST	FALSE		/* SendAck: no more bytes to send */
#define I2C_MORE	TRUE		/* SendAck: more bytes to send */

#define i2c_Start()		i2c_Restart()
#define i2c_WriteTo(address)	i2c_Open((address), I2C_WRITE)
#define i2c_ReadFrom(address)	i2c_Open((address), I2C_READ)

/*
 * Timings for the i2c bus. Times are rounded up to the nearest
 * micro second.
 */

#define I2C_TM_BUS_FREE		5
#define	I2C_TM_START_SU		5
#define I2C_TM_START_HD		4
#define I2C_TM_SCL_LOW		5
#define	I2C_TM_SCL_HIGH		4
#define I2C_TM_DATA_SU		1
#define	I2C_TM_DATA_HD		0
#define I2C_TM_SCL_TO_DATA	4	/* SCL low to data valid */
#define	I2C_TM_STOP_SU		4
#define I2C_TM_SCL_TMO		10	/* clock time out */

extern signed char	i2c_ReadAcknowledge(void);
extern unsigned char	i2c_SendAddress(unsigned char, unsigned char);
extern unsigned char	i2c_SendByte(unsigned char);
extern int		i2c_ReadByte(void);
extern void		i2c_Restart(void);
extern void		i2c_Stop(void);
extern void		i2c_SendAcknowledge(unsigned char);
extern signed char	i2c_PutByte(unsigned char);
extern int		i2c_GetByte(unsigned char);
extern unsigned char	i2c_Open(unsigned char, unsigned char);
extern unsigned char	i2c_GetString(unsigned char *, unsigned char);
extern int		i2c_PutString(const unsigned char *, unsigned char);
extern unsigned char	i2c_WaitForSCL(void);

#endif			/* _I2C_H_ */