ergodone - Refactor use of legacy i2c implementation (#14340)
* Refactor use of legacy i2c implementation * copy-paste error
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					 4 changed files with 15 additions and 417 deletions
				
			
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			@ -1,9 +1,11 @@
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#include <stdbool.h>
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#include "action.h"
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#include "i2cmaster.h"
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#include "i2c_master.h"
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#include "expander.h"
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#include "debug.h"
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#define I2C_TIMEOUT 100
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static uint8_t expander_status = 0;
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static uint8_t expander_input = 0;
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			@ -20,7 +22,7 @@ void expander_init(void)
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void expander_scan(void)
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{
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  dprintf("expander status: %d ... ", expander_status);
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  uint8_t ret = i2c_start(EXPANDER_ADDR | I2C_WRITE);
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  uint8_t ret = i2c_start(EXPANDER_ADDR | I2C_WRITE, I2C_TIMEOUT);
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  if (ret == 0) {
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    i2c_stop();
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    if (expander_status == 0) {
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			@ -90,15 +92,7 @@ uint8_t expander_write(uint8_t reg, uint8_t data)
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  if (expander_status == 0) {
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    return 0;
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  }
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  uint8_t ret;
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  ret = i2c_start(EXPANDER_ADDR | I2C_WRITE);
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  if (ret) goto stop;
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  ret = i2c_write(reg);
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  if (ret) goto stop;
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  ret = i2c_write(data);
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 stop:
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  i2c_stop();
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  return ret;
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  return i2c_writeReg(EXPANDER_ADDR, reg, &data, 1, I2C_TIMEOUT);
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}
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uint8_t expander_read(uint8_t reg, uint8_t *data)
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			@ -106,15 +100,5 @@ uint8_t expander_read(uint8_t reg, uint8_t *data)
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  if (expander_status == 0) {
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    return 0;
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  }
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  uint8_t ret;
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  ret = i2c_start(EXPANDER_ADDR | I2C_WRITE);
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  if (ret) goto stop;
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  ret = i2c_write(reg);
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  if (ret) goto stop;
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  ret = i2c_rep_start(EXPANDER_ADDR | I2C_READ);
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  if (ret) goto stop;
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  *data = i2c_readNak();
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 stop:
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  i2c_stop();
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  return ret;
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  return i2c_readReg(EXPANDER_ADDR, reg, data, 1, I2C_TIMEOUT);
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}
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			@ -1,178 +0,0 @@
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#ifndef _I2CMASTER_H
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#define _I2CMASTER_H   1
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/************************************************************************* 
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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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* 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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* Software: AVR-GCC 3.4.3 / avr-libc 1.2.3
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* Target:   any AVR device
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* Usage:    see Doxygen manual
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**************************************************************************/
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#ifdef DOXYGEN
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/**
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 @defgroup pfleury_ic2master I2C Master library
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 @code #include <i2cmaster.h> @endcode
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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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 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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 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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 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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 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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 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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    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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    Replaced the incorrect quarter period delays found in AVR300 with 
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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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 @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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 @code
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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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 int main(void)
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 {
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     unsigned char ret;
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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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     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(0x75);                        // write value 0x75 to EEPROM
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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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     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_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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     i2c_stop();
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     for(;;);
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 }
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 @endcode
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*/
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#endif /* DOXYGEN */
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/**@{*/
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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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#endif
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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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#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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#define I2C_WRITE   0
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/**
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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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 @return none
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 */
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extern void i2c_init(void);
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/** 
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 @brief Terminates the data transfer and releases the I2C bus 
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 @param void
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 @return none
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 */
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extern void i2c_stop(void);
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/** 
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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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 @retval   0   device accessible 
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 @retval   1   failed to access device 
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 */
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extern unsigned char i2c_start(unsigned char addr);
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/**
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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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 @retval  0 device accessible
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 @retval  1 failed to access device
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 */
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extern unsigned char i2c_rep_start(unsigned char addr);
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/**
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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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 @param    addr address and transfer direction of I2C device
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 @return   none
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 */
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extern void i2c_start_wait(unsigned char addr);
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/**
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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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 @retval   0 write successful
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 @retval   1 write failed
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 */
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extern unsigned char i2c_write(unsigned char data);
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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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 @return   byte read from I2C device
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 */
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extern unsigned char i2c_readAck(void);
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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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 @return   byte read from I2C device
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 */
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extern unsigned char i2c_readNak(void);
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/** 
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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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 @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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 @return   byte read from I2C device
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 */
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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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/**@}*/
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#endif
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			@ -16,7 +16,7 @@ BOOTLOADER = caterina
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#
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CUSTOM_MATRIX           = yes # Custom matrix file for the ErgoDone
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UNICODE_ENABLE          = yes # Unicode
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BOOTMAGIC_ENABLE = lite     # Enable Bootmagic Lite
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BOOTMAGIC_ENABLE        = yes # Enable Bootmagic Lite
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MOUSEKEY_ENABLE         = yes # Mouse keys
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EXTRAKEY_ENABLE         = yes # Audio control and System control
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CONSOLE_ENABLE          = no  # Console for debug
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			@ -29,8 +29,8 @@ SWAP_HANDS_ENABLE       = no  # Disable Onehand
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RGBLIGHT_ENABLE         = no
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# project specific files
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QUANTUM_LIB_SRC += i2c_master.c
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SRC = \
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    twimaster.c \
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    matrix.c   \
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    expander.c \
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			@ -1,208 +0,0 @@
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/*************************************************************************
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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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* 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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* Target:   any AVR device with hardware TWI 
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* Usage:    API compatible with I2C Software Library i2cmaster.h
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**************************************************************************/
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#include <inttypes.h>
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#include <compat/twi.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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#ifndef F_CPU
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#define F_CPU 16000000UL
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#endif
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/* I2C clock in Hz */
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#define SCL_CLOCK  400000L
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/*************************************************************************
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 Initialization of the I2C bus interface. Need to be called only once
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*************************************************************************/
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void i2c_init(void)
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{
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  /* initialize TWI clock
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   * minimal values in Bit Rate Register (TWBR) and minimal Prescaler
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   * bits in the TWI Status Register should give us maximal possible
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   * I2C bus speed - about 444 kHz
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   *
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   * for more details, see 20.5.2 in ATmega16/32 secification
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   */
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  TWSR = 0;     /* no prescaler */
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  TWBR = 10;    /* must be >= 10 for stable operation */
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}/* i2c_init */
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/*************************************************************************	
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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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*************************************************************************/
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unsigned char i2c_start(unsigned char address)
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{
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    uint8_t   twst;
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	// send START condition
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	TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
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	// wait until transmission completed
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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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	twst = TW_STATUS & 0xF8;
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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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	TWDR = address;
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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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	while(!(TWCR & (1<<TWINT)));
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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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	if ( (twst != TW_MT_SLA_ACK) && (twst != TW_MR_SLA_ACK) ) return 1;
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	return 0;
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}/* i2c_start */
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/*************************************************************************
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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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 Input:   address and transfer direction of I2C device
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*************************************************************************/
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void i2c_start_wait(unsigned char address)
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{
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    uint8_t   twst;
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    while ( 1 )
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    {
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	    // send START condition
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	    TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
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    	// wait until transmission completed
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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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    	twst = TW_STATUS & 0xF8;
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    	if ( (twst != TW_START) && (twst != TW_REP_START)) continue;
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    	// send device address
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    	TWDR = address;
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    	TWCR = (1<<TWINT) | (1<<TWEN);
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    	// wail until transmission completed
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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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    	twst = TW_STATUS & 0xF8;
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    	if ( (twst == TW_MT_SLA_NACK )||(twst ==TW_MR_DATA_NACK) ) 
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    	{    	    
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    	    /* device busy, send stop condition to terminate write operation */
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	        TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
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	        // wait until stop condition is executed and bus released
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	        while(TWCR & (1<<TWSTO));
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    	    continue;
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    	}
 | 
			
		||||
    	//if( twst != TW_MT_SLA_ACK) return 1;
 | 
			
		||||
    	break;
 | 
			
		||||
     }
 | 
			
		||||
 | 
			
		||||
}/* i2c_start_wait */
 | 
			
		||||
 | 
			
		||||
 | 
			
		||||
/*************************************************************************
 | 
			
		||||
 Issues a repeated start condition and sends address and transfer direction 
 | 
			
		||||
 | 
			
		||||
 Input:   address and transfer direction of I2C device
 | 
			
		||||
 
 | 
			
		||||
 Return:  0 device accessible
 | 
			
		||||
          1 failed to access device
 | 
			
		||||
*************************************************************************/
 | 
			
		||||
unsigned char i2c_rep_start(unsigned char address)
 | 
			
		||||
{
 | 
			
		||||
    return i2c_start( address );
 | 
			
		||||
 | 
			
		||||
}/* i2c_rep_start */
 | 
			
		||||
 | 
			
		||||
 | 
			
		||||
/*************************************************************************
 | 
			
		||||
 Terminates the data transfer and releases the I2C bus
 | 
			
		||||
*************************************************************************/
 | 
			
		||||
void i2c_stop(void)
 | 
			
		||||
{
 | 
			
		||||
    /* send stop condition */
 | 
			
		||||
	TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
 | 
			
		||||
	
 | 
			
		||||
	// wait until stop condition is executed and bus released
 | 
			
		||||
	while(TWCR & (1<<TWSTO));
 | 
			
		||||
 | 
			
		||||
}/* i2c_stop */
 | 
			
		||||
 | 
			
		||||
 | 
			
		||||
/*************************************************************************
 | 
			
		||||
  Send one byte to I2C device
 | 
			
		||||
  
 | 
			
		||||
  Input:    byte to be transfered
 | 
			
		||||
  Return:   0 write successful 
 | 
			
		||||
            1 write failed
 | 
			
		||||
*************************************************************************/
 | 
			
		||||
unsigned char i2c_write( unsigned char data )
 | 
			
		||||
{	
 | 
			
		||||
    uint8_t   twst;
 | 
			
		||||
    
 | 
			
		||||
	// send data to the previously addressed device
 | 
			
		||||
	TWDR = data;
 | 
			
		||||
	TWCR = (1<<TWINT) | (1<<TWEN);
 | 
			
		||||
 | 
			
		||||
	// wait until transmission completed
 | 
			
		||||
	while(!(TWCR & (1<<TWINT)));
 | 
			
		||||
 | 
			
		||||
	// check value of TWI Status Register. Mask prescaler bits
 | 
			
		||||
	twst = TW_STATUS & 0xF8;
 | 
			
		||||
	if( twst != TW_MT_DATA_ACK) return 1;
 | 
			
		||||
	return 0;
 | 
			
		||||
 | 
			
		||||
}/* i2c_write */
 | 
			
		||||
 | 
			
		||||
 | 
			
		||||
/*************************************************************************
 | 
			
		||||
 Read one byte from the I2C device, request more data from device 
 | 
			
		||||
 
 | 
			
		||||
 Return:  byte read from I2C device
 | 
			
		||||
*************************************************************************/
 | 
			
		||||
unsigned char i2c_readAck(void)
 | 
			
		||||
{
 | 
			
		||||
	TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
 | 
			
		||||
	while(!(TWCR & (1<<TWINT)));    
 | 
			
		||||
 | 
			
		||||
    return TWDR;
 | 
			
		||||
 | 
			
		||||
}/* i2c_readAck */
 | 
			
		||||
 | 
			
		||||
 | 
			
		||||
/*************************************************************************
 | 
			
		||||
 Read one byte from the I2C device, read is followed by a stop condition 
 | 
			
		||||
 
 | 
			
		||||
 Return:  byte read from I2C device
 | 
			
		||||
*************************************************************************/
 | 
			
		||||
unsigned char i2c_readNak(void)
 | 
			
		||||
{
 | 
			
		||||
	TWCR = (1<<TWINT) | (1<<TWEN);
 | 
			
		||||
	while(!(TWCR & (1<<TWINT)));
 | 
			
		||||
	
 | 
			
		||||
    return TWDR;
 | 
			
		||||
 | 
			
		||||
}/* i2c_readNak */
 | 
			
		||||
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