Converting files to Unix-like format
This commit is contained in:
Oleg Kostyuk
parent
6b7921f91b
commit
39da065913
2 changed files with 380 additions and 380 deletions
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#ifndef _I2CMASTER_H
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#ifndef _I2CMASTER_H
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#define _I2CMASTER_H 1
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#define _I2CMASTER_H 1
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/*************************************************************************
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/*************************************************************************
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* Title: C include file for the I2C master interface
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* Title: C include file for the I2C master interface
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* (i2cmaster.S or twimaster.c)
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* (i2cmaster.S or twimaster.c)
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* Author: Peter Fleury <pfleury@gmx.ch> http://jump.to/fleury
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* Author: Peter Fleury <pfleury@gmx.ch> http://jump.to/fleury
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* File: $Id: i2cmaster.h,v 1.10 2005/03/06 22:39:57 Peter Exp $
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* File: $Id: i2cmaster.h,v 1.10 2005/03/06 22:39:57 Peter Exp $
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* Software: AVR-GCC 3.4.3 / avr-libc 1.2.3
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* Software: AVR-GCC 3.4.3 / avr-libc 1.2.3
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* Target: any AVR device
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* Target: any AVR device
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* Usage: see Doxygen manual
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* Usage: see Doxygen manual
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**************************************************************************/
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**************************************************************************/
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#ifdef DOXYGEN
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#ifdef DOXYGEN
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/**
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/**
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@defgroup pfleury_ic2master I2C Master library
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@defgroup pfleury_ic2master I2C Master library
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@code #include <i2cmaster.h> @endcode
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@code #include <i2cmaster.h> @endcode
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@brief I2C (TWI) Master Software Library
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@brief I2C (TWI) Master Software Library
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Basic routines for communicating with I2C slave devices. This single master
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Basic routines for communicating with I2C slave devices. This single master
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implementation is limited to one bus master on the I2C bus.
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implementation is limited to one bus master on the I2C bus.
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This I2c library is implemented as a compact assembler software implementation of the I2C protocol
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This I2c library is implemented as a compact assembler software implementation of the I2C protocol
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which runs on any AVR (i2cmaster.S) and as a TWI hardware interface for all AVR with built-in TWI hardware (twimaster.c).
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which runs on any AVR (i2cmaster.S) and as a TWI hardware interface for all AVR with built-in TWI hardware (twimaster.c).
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Since the API for these two implementations is exactly the same, an application can be linked either against the
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Since the API for these two implementations is exactly the same, an application can be linked either against the
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software I2C implementation or the hardware I2C implementation.
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software I2C implementation or the hardware I2C implementation.
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Use 4.7k pull-up resistor on the SDA and SCL pin.
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Use 4.7k pull-up resistor on the SDA and SCL pin.
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Adapt the SCL and SDA port and pin definitions and eventually the delay routine in the module
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Adapt the SCL and SDA port and pin definitions and eventually the delay routine in the module
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i2cmaster.S to your target when using the software I2C implementation !
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i2cmaster.S to your target when using the software I2C implementation !
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Adjust the CPU clock frequence F_CPU in twimaster.c or in the Makfile when using the TWI hardware implementaion.
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Adjust the CPU clock frequence F_CPU in twimaster.c or in the Makfile when using the TWI hardware implementaion.
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@note
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@note
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The module i2cmaster.S is based on the Atmel Application Note AVR300, corrected and adapted
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The module i2cmaster.S is based on the Atmel Application Note AVR300, corrected and adapted
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to GNU assembler and AVR-GCC C call interface.
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to GNU assembler and AVR-GCC C call interface.
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Replaced the incorrect quarter period delays found in AVR300 with
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Replaced the incorrect quarter period delays found in AVR300 with
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half period delays.
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half period delays.
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@author Peter Fleury pfleury@gmx.ch http://jump.to/fleury
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@author Peter Fleury pfleury@gmx.ch http://jump.to/fleury
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@par API Usage Example
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@par API Usage Example
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The following code shows typical usage of this library, see example test_i2cmaster.c
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The following code shows typical usage of this library, see example test_i2cmaster.c
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@code
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@code
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#include <i2cmaster.h>
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#include <i2cmaster.h>
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#define Dev24C02 0xA2 // device address of EEPROM 24C02, see datasheet
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#define Dev24C02 0xA2 // device address of EEPROM 24C02, see datasheet
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int main(void)
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int main(void)
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{
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{
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unsigned char ret;
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unsigned char ret;
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i2c_init(); // initialize I2C library
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i2c_init(); // initialize I2C library
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// write 0x75 to EEPROM address 5 (Byte Write)
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// write 0x75 to EEPROM address 5 (Byte Write)
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i2c_start_wait(Dev24C02+I2C_WRITE); // set device address and write mode
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i2c_start_wait(Dev24C02+I2C_WRITE); // set device address and write mode
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i2c_write(0x05); // write address = 5
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i2c_write(0x05); // write address = 5
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i2c_write(0x75); // write value 0x75 to EEPROM
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i2c_write(0x75); // write value 0x75 to EEPROM
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i2c_stop(); // set stop conditon = release bus
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i2c_stop(); // set stop conditon = release bus
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// read previously written value back from EEPROM address 5
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// read previously written value back from EEPROM address 5
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i2c_start_wait(Dev24C02+I2C_WRITE); // set device address and write mode
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i2c_start_wait(Dev24C02+I2C_WRITE); // set device address and write mode
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i2c_write(0x05); // write address = 5
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i2c_write(0x05); // write address = 5
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i2c_rep_start(Dev24C02+I2C_READ); // set device address and read mode
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i2c_rep_start(Dev24C02+I2C_READ); // set device address and read mode
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ret = i2c_readNak(); // read one byte from EEPROM
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ret = i2c_readNak(); // read one byte from EEPROM
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i2c_stop();
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i2c_stop();
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for(;;);
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for(;;);
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}
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}
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@endcode
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@endcode
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*/
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*/
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#endif /* DOXYGEN */
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#endif /* DOXYGEN */
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/**@{*/
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/**@{*/
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#if (__GNUC__ * 100 + __GNUC_MINOR__) < 304
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#if (__GNUC__ * 100 + __GNUC_MINOR__) < 304
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#error "This library requires AVR-GCC 3.4 or later, update to newer AVR-GCC compiler !"
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#error "This library requires AVR-GCC 3.4 or later, update to newer AVR-GCC compiler !"
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#endif
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#endif
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#include <avr/io.h>
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#include <avr/io.h>
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/** defines the data direction (reading from I2C device) in i2c_start(),i2c_rep_start() */
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/** defines the data direction (reading from I2C device) in i2c_start(),i2c_rep_start() */
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#define I2C_READ 1
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#define I2C_READ 1
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/** defines the data direction (writing to I2C device) in i2c_start(),i2c_rep_start() */
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/** defines the data direction (writing to I2C device) in i2c_start(),i2c_rep_start() */
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#define I2C_WRITE 0
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#define I2C_WRITE 0
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/**
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/**
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@brief initialize the I2C master interace. Need to be called only once
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@brief initialize the I2C master interace. Need to be called only once
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@param void
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@param void
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@return none
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@return none
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*/
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*/
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extern void i2c_init(void);
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extern void i2c_init(void);
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/**
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/**
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@brief Terminates the data transfer and releases the I2C bus
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@brief Terminates the data transfer and releases the I2C bus
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@param void
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@param void
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@return none
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@return none
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*/
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*/
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extern void i2c_stop(void);
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extern void i2c_stop(void);
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/**
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/**
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@brief Issues a start condition and sends address and transfer direction
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@brief Issues a start condition and sends address and transfer direction
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@param addr address and transfer direction of I2C device
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@param addr address and transfer direction of I2C device
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@retval 0 device accessible
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@retval 0 device accessible
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@retval 1 failed to access device
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@retval 1 failed to access device
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*/
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*/
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extern unsigned char i2c_start(unsigned char addr);
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extern unsigned char i2c_start(unsigned char addr);
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/**
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/**
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@brief Issues a repeated start condition and sends address and transfer direction
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@brief Issues a repeated start condition and sends address and transfer direction
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@param addr address and transfer direction of I2C device
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@param addr address and transfer direction of I2C device
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@retval 0 device accessible
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@retval 0 device accessible
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@retval 1 failed to access device
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@retval 1 failed to access device
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*/
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*/
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extern unsigned char i2c_rep_start(unsigned char addr);
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extern unsigned char i2c_rep_start(unsigned char addr);
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/**
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/**
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@brief Issues a start condition and sends address and transfer direction
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@brief Issues a start condition and sends address and transfer direction
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If device is busy, use ack polling to wait until device ready
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If device is busy, use ack polling to wait until device ready
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@param addr address and transfer direction of I2C device
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@param addr address and transfer direction of I2C device
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@return none
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@return none
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*/
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*/
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extern void i2c_start_wait(unsigned char addr);
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extern void i2c_start_wait(unsigned char addr);
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/**
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/**
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@brief Send one byte to I2C device
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@brief Send one byte to I2C device
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@param data byte to be transfered
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@param data byte to be transfered
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@retval 0 write successful
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@retval 0 write successful
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@retval 1 write failed
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@retval 1 write failed
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*/
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*/
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extern unsigned char i2c_write(unsigned char data);
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extern unsigned char i2c_write(unsigned char data);
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/**
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/**
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@brief read one byte from the I2C device, request more data from device
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@brief read one byte from the I2C device, request more data from device
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@return byte read from I2C device
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@return byte read from I2C device
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*/
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*/
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extern unsigned char i2c_readAck(void);
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extern unsigned char i2c_readAck(void);
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/**
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/**
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@brief read one byte from the I2C device, read is followed by a stop condition
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@brief read one byte from the I2C device, read is followed by a stop condition
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@return byte read from I2C device
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@return byte read from I2C device
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*/
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*/
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extern unsigned char i2c_readNak(void);
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extern unsigned char i2c_readNak(void);
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/**
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/**
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@brief read one byte from the I2C device
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@brief read one byte from the I2C device
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Implemented as a macro, which calls either i2c_readAck or i2c_readNak
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Implemented as a macro, which calls either i2c_readAck or i2c_readNak
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@param ack 1 send ack, request more data from device<br>
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@param ack 1 send ack, request more data from device<br>
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0 send nak, read is followed by a stop condition
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0 send nak, read is followed by a stop condition
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@return byte read from I2C device
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@return byte read from I2C device
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*/
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*/
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extern unsigned char i2c_read(unsigned char ack);
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extern unsigned char i2c_read(unsigned char ack);
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#define i2c_read(ack) (ack) ? i2c_readAck() : i2c_readNak();
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#define i2c_read(ack) (ack) ? i2c_readAck() : i2c_readNak();
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/**@}*/
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/**@}*/
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#endif
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#endif
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@ -1,202 +1,202 @@
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/*************************************************************************
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/*************************************************************************
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* Title: I2C master library using hardware TWI interface
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* Title: I2C master library using hardware TWI interface
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* Author: Peter Fleury <pfleury@gmx.ch> http://jump.to/fleury
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* Author: Peter Fleury <pfleury@gmx.ch> http://jump.to/fleury
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* File: $Id: twimaster.c,v 1.3 2005/07/02 11:14:21 Peter Exp $
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* File: $Id: twimaster.c,v 1.3 2005/07/02 11:14:21 Peter Exp $
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* Software: AVR-GCC 3.4.3 / avr-libc 1.2.3
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* Software: AVR-GCC 3.4.3 / avr-libc 1.2.3
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* Target: any AVR device with hardware TWI
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* Target: any AVR device with hardware TWI
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* Usage: API compatible with I2C Software Library i2cmaster.h
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* Usage: API compatible with I2C Software Library i2cmaster.h
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**************************************************************************/
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**************************************************************************/
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#include <inttypes.h>
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#include <inttypes.h>
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#include <compat/twi.h>
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#include <compat/twi.h>
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#include <i2cmaster.h>
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#include <i2cmaster.h>
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/* define CPU frequency in Mhz here if not defined in Makefile */
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/* define CPU frequency in Mhz here if not defined in Makefile */
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#ifndef F_CPU
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#ifndef F_CPU
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#define F_CPU 4000000UL
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#define F_CPU 4000000UL
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#endif
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#endif
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/* I2C clock in Hz */
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/* I2C clock in Hz */
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#define SCL_CLOCK 100000L
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#define SCL_CLOCK 100000L
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/*************************************************************************
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/*************************************************************************
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Initialization of the I2C bus interface. Need to be called only once
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Initialization of the I2C bus interface. Need to be called only once
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*************************************************************************/
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*************************************************************************/
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void i2c_init(void)
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void i2c_init(void)
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{
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{
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/* initialize TWI clock: 100 kHz clock, TWPS = 0 => prescaler = 1 */
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/* initialize TWI clock: 100 kHz clock, TWPS = 0 => prescaler = 1 */
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TWSR = 0; /* no prescaler */
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TWSR = 0; /* no prescaler */
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TWBR = ((F_CPU/SCL_CLOCK)-16)/2; /* must be > 10 for stable operation */
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TWBR = ((F_CPU/SCL_CLOCK)-16)/2; /* must be > 10 for stable operation */
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}/* i2c_init */
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}/* i2c_init */
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/*************************************************************************
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/*************************************************************************
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Issues a start condition and sends address and transfer direction.
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Issues a start condition and sends address and transfer direction.
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return 0 = device accessible, 1= failed to access device
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return 0 = device accessible, 1= failed to access device
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*************************************************************************/
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*************************************************************************/
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unsigned char i2c_start(unsigned char address)
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unsigned char i2c_start(unsigned char address)
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{
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{
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uint8_t twst;
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uint8_t twst;
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// send START condition
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// send START condition
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TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
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TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
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// wait until transmission completed
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// wait until transmission completed
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while(!(TWCR & (1<<TWINT)));
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while(!(TWCR & (1<<TWINT)));
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// check value of TWI Status Register. Mask prescaler bits.
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// check value of TWI Status Register. Mask prescaler bits.
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twst = TW_STATUS & 0xF8;
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twst = TW_STATUS & 0xF8;
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if ( (twst != TW_START) && (twst != TW_REP_START)) return 1;
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if ( (twst != TW_START) && (twst != TW_REP_START)) return 1;
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// send device address
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// send device address
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TWDR = address;
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TWDR = address;
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TWCR = (1<<TWINT) | (1<<TWEN);
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TWCR = (1<<TWINT) | (1<<TWEN);
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// wail until transmission completed and ACK/NACK has been received
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// wail until transmission completed and ACK/NACK has been received
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while(!(TWCR & (1<<TWINT)));
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while(!(TWCR & (1<<TWINT)));
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// check value of TWI Status Register. Mask prescaler bits.
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// check value of TWI Status Register. Mask prescaler bits.
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twst = TW_STATUS & 0xF8;
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twst = TW_STATUS & 0xF8;
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if ( (twst != TW_MT_SLA_ACK) && (twst != TW_MR_SLA_ACK) ) return 1;
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if ( (twst != TW_MT_SLA_ACK) && (twst != TW_MR_SLA_ACK) ) return 1;
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return 0;
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return 0;
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}/* i2c_start */
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}/* i2c_start */
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/*************************************************************************
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/*************************************************************************
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Issues a start condition and sends address and transfer direction.
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Issues a start condition and sends address and transfer direction.
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If device is busy, use ack polling to wait until device is ready
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If device is busy, use ack polling to wait until device is ready
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Input: address and transfer direction of I2C device
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Input: address and transfer direction of I2C device
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*************************************************************************/
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*************************************************************************/
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void i2c_start_wait(unsigned char address)
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void i2c_start_wait(unsigned char address)
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{
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{
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uint8_t twst;
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uint8_t twst;
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while ( 1 )
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while ( 1 )
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{
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{
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// send START condition
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// send START condition
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TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
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TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
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// wait until transmission completed
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// wait until transmission completed
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while(!(TWCR & (1<<TWINT)));
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while(!(TWCR & (1<<TWINT)));
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// check value of TWI Status Register. Mask prescaler bits.
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// check value of TWI Status Register. Mask prescaler bits.
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twst = TW_STATUS & 0xF8;
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twst = TW_STATUS & 0xF8;
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if ( (twst != TW_START) && (twst != TW_REP_START)) continue;
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if ( (twst != TW_START) && (twst != TW_REP_START)) continue;
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// send device address
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// send device address
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TWDR = address;
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TWDR = address;
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TWCR = (1<<TWINT) | (1<<TWEN);
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TWCR = (1<<TWINT) | (1<<TWEN);
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|
||||||
// wail until transmission completed
|
// wail until transmission completed
|
||||||
while(!(TWCR & (1<<TWINT)));
|
while(!(TWCR & (1<<TWINT)));
|
||||||
|
|
||||||
// check value of TWI Status Register. Mask prescaler bits.
|
// check value of TWI Status Register. Mask prescaler bits.
|
||||||
twst = TW_STATUS & 0xF8;
|
twst = TW_STATUS & 0xF8;
|
||||||
if ( (twst == TW_MT_SLA_NACK )||(twst ==TW_MR_DATA_NACK) )
|
if ( (twst == TW_MT_SLA_NACK )||(twst ==TW_MR_DATA_NACK) )
|
||||||
{
|
{
|
||||||
/* device busy, send stop condition to terminate write operation */
|
/* device busy, send stop condition to terminate write operation */
|
||||||
TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
|
TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
|
||||||
|
|
||||||
// wait until stop condition is executed and bus released
|
// wait until stop condition is executed and bus released
|
||||||
while(TWCR & (1<<TWSTO));
|
while(TWCR & (1<<TWSTO));
|
||||||
|
|
||||||
continue;
|
continue;
|
||||||
}
|
}
|
||||||
//if( twst != TW_MT_SLA_ACK) return 1;
|
//if( twst != TW_MT_SLA_ACK) return 1;
|
||||||
break;
|
break;
|
||||||
}
|
}
|
||||||
|
|
||||||
}/* i2c_start_wait */
|
}/* i2c_start_wait */
|
||||||
|
|
||||||
|
|
||||||
/*************************************************************************
|
/*************************************************************************
|
||||||
Issues a repeated start condition and sends address and transfer direction
|
Issues a repeated start condition and sends address and transfer direction
|
||||||
|
|
||||||
Input: address and transfer direction of I2C device
|
Input: address and transfer direction of I2C device
|
||||||
|
|
||||||
Return: 0 device accessible
|
Return: 0 device accessible
|
||||||
1 failed to access device
|
1 failed to access device
|
||||||
*************************************************************************/
|
*************************************************************************/
|
||||||
unsigned char i2c_rep_start(unsigned char address)
|
unsigned char i2c_rep_start(unsigned char address)
|
||||||
{
|
{
|
||||||
return i2c_start( address );
|
return i2c_start( address );
|
||||||
|
|
||||||
}/* i2c_rep_start */
|
}/* i2c_rep_start */
|
||||||
|
|
||||||
|
|
||||||
/*************************************************************************
|
/*************************************************************************
|
||||||
Terminates the data transfer and releases the I2C bus
|
Terminates the data transfer and releases the I2C bus
|
||||||
*************************************************************************/
|
*************************************************************************/
|
||||||
void i2c_stop(void)
|
void i2c_stop(void)
|
||||||
{
|
{
|
||||||
/* send stop condition */
|
/* send stop condition */
|
||||||
TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
|
TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
|
||||||
|
|
||||||
// wait until stop condition is executed and bus released
|
// wait until stop condition is executed and bus released
|
||||||
while(TWCR & (1<<TWSTO));
|
while(TWCR & (1<<TWSTO));
|
||||||
|
|
||||||
}/* i2c_stop */
|
}/* i2c_stop */
|
||||||
|
|
||||||
|
|
||||||
/*************************************************************************
|
/*************************************************************************
|
||||||
Send one byte to I2C device
|
Send one byte to I2C device
|
||||||
|
|
||||||
Input: byte to be transfered
|
Input: byte to be transfered
|
||||||
Return: 0 write successful
|
Return: 0 write successful
|
||||||
1 write failed
|
1 write failed
|
||||||
*************************************************************************/
|
*************************************************************************/
|
||||||
unsigned char i2c_write( unsigned char data )
|
unsigned char i2c_write( unsigned char data )
|
||||||
{
|
{
|
||||||
uint8_t twst;
|
uint8_t twst;
|
||||||
|
|
||||||
// send data to the previously addressed device
|
// send data to the previously addressed device
|
||||||
TWDR = data;
|
TWDR = data;
|
||||||
TWCR = (1<<TWINT) | (1<<TWEN);
|
TWCR = (1<<TWINT) | (1<<TWEN);
|
||||||
|
|
||||||
// wait until transmission completed
|
// wait until transmission completed
|
||||||
while(!(TWCR & (1<<TWINT)));
|
while(!(TWCR & (1<<TWINT)));
|
||||||
|
|
||||||
// check value of TWI Status Register. Mask prescaler bits
|
// check value of TWI Status Register. Mask prescaler bits
|
||||||
twst = TW_STATUS & 0xF8;
|
twst = TW_STATUS & 0xF8;
|
||||||
if( twst != TW_MT_DATA_ACK) return 1;
|
if( twst != TW_MT_DATA_ACK) return 1;
|
||||||
return 0;
|
return 0;
|
||||||
|
|
||||||
}/* i2c_write */
|
}/* i2c_write */
|
||||||
|
|
||||||
|
|
||||||
/*************************************************************************
|
/*************************************************************************
|
||||||
Read one byte from the I2C device, request more data from device
|
Read one byte from the I2C device, request more data from device
|
||||||
|
|
||||||
Return: byte read from I2C device
|
Return: byte read from I2C device
|
||||||
*************************************************************************/
|
*************************************************************************/
|
||||||
unsigned char i2c_readAck(void)
|
unsigned char i2c_readAck(void)
|
||||||
{
|
{
|
||||||
TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
|
TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
|
||||||
while(!(TWCR & (1<<TWINT)));
|
while(!(TWCR & (1<<TWINT)));
|
||||||
|
|
||||||
return TWDR;
|
return TWDR;
|
||||||
|
|
||||||
}/* i2c_readAck */
|
}/* i2c_readAck */
|
||||||
|
|
||||||
|
|
||||||
/*************************************************************************
|
/*************************************************************************
|
||||||
Read one byte from the I2C device, read is followed by a stop condition
|
Read one byte from the I2C device, read is followed by a stop condition
|
||||||
|
|
||||||
Return: byte read from I2C device
|
Return: byte read from I2C device
|
||||||
*************************************************************************/
|
*************************************************************************/
|
||||||
unsigned char i2c_readNak(void)
|
unsigned char i2c_readNak(void)
|
||||||
{
|
{
|
||||||
TWCR = (1<<TWINT) | (1<<TWEN);
|
TWCR = (1<<TWINT) | (1<<TWEN);
|
||||||
while(!(TWCR & (1<<TWINT)));
|
while(!(TWCR & (1<<TWINT)));
|
||||||
|
|
||||||
return TWDR;
|
return TWDR;
|
||||||
|
|
||||||
}/* i2c_readNak */
|
}/* i2c_readNak */
|
||||||
|
|
|
||||||
Loading…
Add table
Reference in a new issue