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/****************************************************************************
Title : C include file for the I2C FUNCTIONS library (i2c.h)
Author: Chris efstathiou hendrix@otenet.gr
Date: 13/Jul/2002
Software: AVR-GCC with AVR-AS
Target: any AVR device
Comments: This software is FREE.
*****************************************************************************/
#ifndef I2C_H
#define I2C_H 1
/*##############################################################################################*/
/* START OF CONFIGURATION BLOCK */
/*##############################################################################################*/
#ifndef F_CPU
#define F_CPU 3686400L /* The cpu clock frequency in Hertz (used to calculate time)*/
#endif
#define I2C_SDA_PORT D /* The SDA port. Use capital letter (A,B,C,D... etc.) */
#define SDA_PIN 4 /* The SDA port pin */
#define I2C_SCL_PORT D /* The SCL port. Use capital letter (A,B,C,D... etc.) */
#define SCL_PIN 5 /* The SCL port pin */
/*
The I2C_DELAY_TIME normally is 5 microseconds for a 100 Khz I2C bus ( (1/100000)/2 ).
but due to bus capacitance and device responce time in my application i use 50 microseconds.
The I2C_TIMEOUT_TIME is set to whatever is the maximum time you think your device will take
to perform the requested task. After that time the i2c_transmit function will return
a "I2C_ERROR_DEVICE_NOT_RESPONDING" or "I2C_ERROR_DEVICE_BUSY" error code.
*/
#define I2C_DELAY_TIME 50 /* in microseconds (max over 1 second) */
#define I2C_TIMEOUT_TIME 1000 /* in microseconds (max over 1 second) */
/*##############################################################################################*/
/* END OF CONFIGURATION BLOCK */
/*##############################################################################################*/
/* Keyword definitions */
#define I2C_READ 1
#define I2C_WRITE 0
#define I2C_QUIT 0
#define I2C_CONTINUE 1
#define I2C_NO_ERROR 0
#define I2C_ERROR_DEVICE_BUSY 1
#define I2C_ERROR_DEVICE_NOT_RESPONDING 2
/* Function Declaration */
extern void i2c_init(void);
extern void i2c_start(void);
extern void i2c_stop(void);
extern unsigned char i2c_transmit(unsigned char data);
extern unsigned char i2c_receive(unsigned char ack);
/* Macro definitions */
#define I2C_START(ADDRESS) { i2c_start(); i2c_transmit(ADDRESS); }
#define I2C_START_TX(ADDRESS) I2C_START(ADDRESS)
#define I2C_START_RX(ADDRESS) I2C_START(ADDRESS | I2C_READ)
#endif /* #ifndef I2C_H */
/*######################################################################################################*/
/* T H E E N D */
/*######################################################################################################*/