+++ /dev/null
-#ifndef _I2CMASTER_H
-#define _I2CMASTER_H 1
-/*************************************************************************
-* Title: C include file for the I2C master interface
-* (i2cmaster.S or twimaster.c)
-* Author: Peter Fleury <pfleury@gmx.ch> http://jump.to/fleury
-* File: $Id: i2cmaster.h,v 1.10 2005/03/06 22:39:57 Peter Exp $
-* Software: AVR-GCC 3.4.3 / avr-libc 1.2.3
-* Target: any AVR device
-* Usage: see Doxygen manual
-**************************************************************************/
-
-#ifdef DOXYGEN
-/**
- @defgroup pfleury_ic2master I2C Master library
- @code #include <i2cmaster.h> @endcode
-
- @brief I2C (TWI) Master Software Library
-
- Basic routines for communicating with I2C slave devices. This single master
- implementation is limited to one bus master on the I2C bus.
-
- This I2c library is implemented as a compact assembler software implementation of the I2C protocol
- which runs on any AVR (i2cmaster.S) and as a TWI hardware interface for all AVR with built-in TWI hardware (twimaster.c).
- Since the API for these two implementations is exactly the same, an application can be linked either against the
- software I2C implementation or the hardware I2C implementation.
-
- Use 4.7k pull-up resistor on the SDA and SCL pin.
-
- Adapt the SCL and SDA port and pin definitions and eventually the delay routine in the module
- i2cmaster.S to your target when using the software I2C implementation !
-
- Adjust the CPU clock frequence F_CPU in twimaster.c or in the Makfile when using the TWI hardware implementaion.
-
- @note
- The module i2cmaster.S is based on the Atmel Application Note AVR300, corrected and adapted
- to GNU assembler and AVR-GCC C call interface.
- Replaced the incorrect quarter period delays found in AVR300 with
- half period delays.
-
- @author Peter Fleury pfleury@gmx.ch http://jump.to/fleury
-
- @par API Usage Example
- The following code shows typical usage of this library, see example test_i2cmaster.c
-
- @code
-
- #include <i2cmaster.h>
-
-
- #define Dev24C02 0xA2 // device address of EEPROM 24C02, see datasheet
-
- int main(void)
- {
- unsigned char ret;
-
- i2c_init(); // initialize I2C library
-
- // write 0x75 to EEPROM address 5 (Byte Write)
- i2c_start_wait(Dev24C02+I2C_WRITE); // set device address and write mode
- i2c_write(0x05); // write address = 5
- i2c_write(0x75); // write value 0x75 to EEPROM
- i2c_stop(); // set stop conditon = release bus
-
-
- // read previously written value back from EEPROM address 5
- i2c_start_wait(Dev24C02+I2C_WRITE); // set device address and write mode
-
- i2c_write(0x05); // write address = 5
- i2c_rep_start(Dev24C02+I2C_READ); // set device address and read mode
-
- ret = i2c_readNak(); // read one byte from EEPROM
- i2c_stop();
-
- for(;;);
- }
- @endcode
-
-*/
-#endif /* DOXYGEN */
-
-/**@{*/
-
-#if (__GNUC__ * 100 + __GNUC_MINOR__) < 304
-#error "This library requires AVR-GCC 3.4 or later, update to newer AVR-GCC compiler !"
-#endif
-
-#include <avr/io.h>
-
-/** defines the data direction (reading from I2C device) in i2c_start(),i2c_rep_start() */
-#define I2C_READ 1
-
-/** defines the data direction (writing to I2C device) in i2c_start(),i2c_rep_start() */
-#define I2C_WRITE 0
-
-
-/**
- @brief initialize the I2C master interace. Need to be called only once
- @param void
- @return none
- */
-extern void i2c_init(void);
-
-
-/**
- @brief Terminates the data transfer and releases the I2C bus
- @param void
- @return none
- */
-extern void i2c_stop(void);
-
-
-/**
- @brief Issues a start condition and sends address and transfer direction
-
- @param addr address and transfer direction of I2C device
- @retval 0 device accessible
- @retval 1 failed to access device
- */
-extern unsigned char i2c_start(unsigned char addr);
-
-
-/**
- @brief Issues a repeated start condition and sends address and transfer direction
-
- @param addr address and transfer direction of I2C device
- @retval 0 device accessible
- @retval 1 failed to access device
- */
-extern unsigned char i2c_rep_start(unsigned char addr);
-
-
-/**
- @brief Issues a start condition and sends address and transfer direction
-
- If device is busy, use ack polling to wait until device ready
- @param addr address and transfer direction of I2C device
- @return none
- */
-extern void i2c_start_wait(unsigned char addr);
-
-
-/**
- @brief Send one byte to I2C device
- @param data byte to be transfered
- @retval 0 write successful
- @retval 1 write failed
- */
-extern unsigned char i2c_write(unsigned char data);
-
-
-/**
- @brief read one byte from the I2C device, request more data from device
- @return byte read from I2C device
- */
-extern unsigned char i2c_readAck(void);
-
-/**
- @brief read one byte from the I2C device, read is followed by a stop condition
- @return byte read from I2C device
- */
-extern unsigned char i2c_readNak(void);
-
-/**
- @brief read one byte from the I2C device
-
- Implemented as a macro, which calls either i2c_readAck or i2c_readNak
-
- @param ack 1 send ack, request more data from device<br>
- 0 send nak, read is followed by a stop condition
- @return byte read from I2C device
- */
-extern unsigned char i2c_read(unsigned char ack);
-#define i2c_read(ack) (ack) ? i2c_readAck() : i2c_readNak();
-
-
-/**@}*/
-#endif
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