Refactor use of legacy i2c implementation (#14341)
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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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			@ -243,15 +243,11 @@ static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row)
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        /* if there was an error */
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        return 0;
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    } else {
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        uint16_t data = 0;
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        mcp23018_status = i2c_start(I2C_ADDR_WRITE);    if (mcp23018_status) goto out;
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        mcp23018_status = i2c_write(GPIOA);             if (mcp23018_status) goto out;
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        mcp23018_status = i2c_start(I2C_ADDR_READ);     if (mcp23018_status) goto out;
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        data = i2c_readNak();
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        data = ~data;
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    out:
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        i2c_stop();
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        current_matrix[current_row] |= (data << 8);
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        uint8_t data = 0;
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        mcp23018_status = i2c_readReg(I2C_ADDR, GPIOA, &data, 1, I2C_TIMEOUT);
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        if (!mcp23018_status) {
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            current_matrix[current_row] |= (~((uint16_t)data) << 8);
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        }
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    }
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    /* For each col... */
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			@ -278,11 +274,8 @@ static void select_row(uint8_t row)
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        /* set active row low  : 0
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           set active row output : 1
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           set other rows hi-Z : 1 */
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        mcp23018_status = i2c_start(I2C_ADDR_WRITE);   if (mcp23018_status) goto out;
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        mcp23018_status = i2c_write(GPIOB);            if (mcp23018_status) goto out;
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        mcp23018_status = i2c_write(0xFF & ~(1<<abs(row-4))); if (mcp23018_status) goto out;
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    out:
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        i2c_stop();
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        uint8_t port = 0xFF & ~(1<<abs(row-4));
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        mcp23018_status = i2c_writeReg(I2C_ADDR, GPIOB, &port, 1, I2C_TIMEOUT);
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    }
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    uint8_t pin = row_pins[row];
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			@ -27,5 +27,5 @@ RGBLIGHT_ENABLE = no
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CUSTOM_MATRIX = yes
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# project specific files
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SRC =  twimaster.c \
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  matrix.c
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QUANTUM_LIB_SRC += i2c_master.c
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SRC += matrix.c
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			@ -1,5 +1,5 @@
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#include "sx60.h"
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#include "i2cmaster.h"
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#include "i2c_master.h"
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bool i2c_initialized = 0;
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			@ -18,21 +18,18 @@ uint8_t init_mcp23018(void) {
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    /* B Pins are Row, A pins are Columns 
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       Set them to output */
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    mcp23018_status = i2c_start(I2C_ADDR_WRITE);    if (mcp23018_status) goto out;
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    mcp23018_status = i2c_write(IODIRA);            if (mcp23018_status) goto out;
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    mcp23018_status = i2c_write(0b11111111);        if (mcp23018_status) goto out;
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    /* Now write to IODIRB */
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    mcp23018_status = i2c_write(0b00000000);        if (mcp23018_status) goto out;
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    i2c_stop();
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    static uint8_t direction[2] = {
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        0b11111111,
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        0b00000000,
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    };
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    static uint8_t pullup[2] = {
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        0b11111111,
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        0b00000000,
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    };
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    mcp23018_status = i2c_start(I2C_ADDR_WRITE);    if (mcp23018_status) goto out;
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    mcp23018_status = i2c_write(GPPUA);             if (mcp23018_status) goto out;
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    mcp23018_status = i2c_write(0b11111111);        if (mcp23018_status) goto out;
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    /* Now write to GPPUB */
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    mcp23018_status = i2c_write(0b00000000);        if (mcp23018_status) goto out;
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out:
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    i2c_stop();
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    mcp23018_status = i2c_writeReg(I2C_ADDR, IODIRA, direction, 2, I2C_TIMEOUT);
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    if (mcp23018_status) return mcp23018_status;
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    mcp23018_status = i2c_writeReg(I2C_ADDR, GPPUA, pullup, 2, I2C_TIMEOUT);
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    return mcp23018_status;
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}
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			@ -4,13 +4,12 @@
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#include "quantum.h"
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#include <stdint.h>
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#include <stdbool.h>
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#include "i2cmaster.h"
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#include "i2c_master.h"
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#include <util/delay.h>
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/* I2C aliases and register addresses (see "mcp23018.md") */
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#define I2C_ADDR        0b0100000
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#define I2C_ADDR_WRITE  ( (I2C_ADDR<<1) | I2C_WRITE )
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#define I2C_ADDR_READ   ( (I2C_ADDR<<1) | I2C_READ  )
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#define I2C_TIMEOUT     100
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#define IODIRA          0x00            /* i/o direction register */
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#define IODIRB          0x01
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#define GPPUA           0x0C            /* GPIO pull-up resistor register */
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			@ -1,207 +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 Hz 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.
 | 
			
		||||
 If device is busy, use ack polling to wait until device is ready
 | 
			
		||||
 | 
			
		||||
 Input:   address and transfer direction of I2C device
 | 
			
		||||
*************************************************************************/
 | 
			
		||||
void i2c_start_wait(unsigned char address)
 | 
			
		||||
{
 | 
			
		||||
    uint8_t   twst;
 | 
			
		||||
 | 
			
		||||
 | 
			
		||||
    while ( 1 )
 | 
			
		||||
    {
 | 
			
		||||
      /* send START condition */
 | 
			
		||||
      TWCR = (1<<TWINT) | (1<<TWSTA) | (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_START) && (twst != TW_REP_START)) continue;
 | 
			
		||||
 | 
			
		||||
      /* send device address */
 | 
			
		||||
      TWDR = address;
 | 
			
		||||
      TWCR = (1<<TWINT) | (1<<TWEN);
 | 
			
		||||
 | 
			
		||||
      /* wail until transmission completed */
 | 
			
		||||
      while(!(TWCR & (1<<TWINT)));
 | 
			
		||||
 | 
			
		||||
      /* check value of TWI Status Register. Mask prescaler bits. */
 | 
			
		||||
      twst = TW_STATUS & 0xF8;
 | 
			
		||||
      if ( (twst == TW_MT_SLA_NACK )||(twst ==TW_MR_DATA_NACK) )
 | 
			
		||||
      {
 | 
			
		||||
          /* device busy, send stop condition to terminate write operation */
 | 
			
		||||
          TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
 | 
			
		||||
 | 
			
		||||
          /* wait until stop condition is executed and bus released */
 | 
			
		||||
          while(TWCR & (1<<TWSTO));
 | 
			
		||||
 | 
			
		||||
          continue;
 | 
			
		||||
      }
 | 
			
		||||
      
 | 
			
		||||
      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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