forked from mirrors/qmk_firmware
handwired/dactyl - Refactor use of legacy i2c implementation (#14344)
This commit is contained in:
Joel Challis
GitHub
parent
04c0704b28
commit
60c5bd7b5e
6 changed files with 52 additions and 442 deletions
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@ -1,5 +1,4 @@
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#include "dactyl.h"
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#include "i2cmaster.h"
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#ifdef SWAP_HANDS_ENABLE
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__attribute__ ((weak))
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@ -4,12 +4,11 @@
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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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#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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@ -1,178 +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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@ -25,7 +25,7 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
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#include "util.h"
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#include "matrix.h"
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#include "dactyl.h"
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#include "i2cmaster.h"
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#include "i2c_master.h"
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#include "timer.h"
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@ -147,9 +147,6 @@ void init_expander(void) {
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#endif
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}
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expander_status = i2c_start(I2C_ADDR_WRITE); if (expander_status) goto out;
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expander_status = i2c_write(IODIRA); if (expander_status) goto out;
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/*
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Pin direction and pull-up depends on both the diode direction
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and on whether the column register is GPIOA or GPIOB
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@ -164,50 +161,65 @@ void init_expander(void) {
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#if (EXPANDER_COL_REGISTER == GPIOA)
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# if (DIODE_DIRECTION == COL2ROW)
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expander_status = i2c_write(expander_input_pin_mask); if (expander_status) goto out;
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expander_status = i2c_write(0); if (expander_status) goto out;
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uint8_t direction[2] = {
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expander_input_pin_mask,
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0,
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};
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# elif (DIODE_DIRECTION == ROW2COL)
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expander_status = i2c_write(0); if (expander_status) goto out;
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expander_status = i2c_write(expander_input_pin_mask); if (expander_status) goto out;
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uint8_t direction[2] = {
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0,
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expander_input_pin_mask,
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};
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# endif
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#elif (EXPANDER_COL_REGISTER == GPIOB)
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# if (DIODE_DIRECTION == COL2ROW)
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expander_status = i2c_write(0); if (expander_status) goto out;
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expander_status = i2c_write(expander_input_pin_mask); if (expander_status) goto out;
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uint8_t direction[2] = {
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0,
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expander_input_pin_mask,
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};
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# elif (DIODE_DIRECTION == ROW2COL)
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expander_status = i2c_write(expander_input_pin_mask); if (expander_status) goto out;
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expander_status = i2c_write(0); if (expander_status) goto out;
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uint8_t direction[2] = {
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expander_input_pin_mask,
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0,
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};
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# endif
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#endif
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i2c_stop();
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// set pull-up
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// - unused : off : 0
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// - input : on : 1
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// - driving : off : 0
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expander_status = i2c_start(I2C_ADDR_WRITE); if (expander_status) goto out;
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expander_status = i2c_write(GPPUA); if (expander_status) goto out;
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#if (EXPANDER_COL_REGISTER == GPIOA)
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# if (DIODE_DIRECTION == COL2ROW)
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expander_status = i2c_write(expander_input_pin_mask); if (expander_status) goto out;
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expander_status = i2c_write(0); if (expander_status) goto out;
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uint8_t pullup[2] = {
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expander_input_pin_mask,
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0,
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};
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# elif (DIODE_DIRECTION == ROW2COL)
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expander_status = i2c_write(0); if (expander_status) goto out;
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expander_status = i2c_write(expander_input_pin_mask); if (expander_status) goto out;
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uint8_t pullup[2] = {
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0,
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expander_input_pin_mask,
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};
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# endif
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#elif (EXPANDER_COL_REGISTER == GPIOB)
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# if (DIODE_DIRECTION == COL2ROW)
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expander_status = i2c_write(0); if (expander_status) goto out;
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expander_status = i2c_write(expander_input_pin_mask); if (expander_status) goto out;
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uint8_t pullup[2] = {
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0,
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expander_input_pin_mask,
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};
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# elif (DIODE_DIRECTION == ROW2COL)
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expander_status = i2c_write(expander_input_pin_mask); if (expander_status) goto out;
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expander_status = i2c_write(0); if (expander_status) goto out;
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uint8_t pullup[2] = {
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expander_input_pin_mask,
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0,
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};
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# endif
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#endif
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out:
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i2c_stop();
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expander_status = i2c_writeReg(I2C_ADDR, IODIRA, direction, 2, I2C_TIMEOUT);
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if (expander_status) return;
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expander_status = i2c_writeReg(I2C_ADDR, GPPUA, pullup, 2, I2C_TIMEOUT);
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}
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uint8_t matrix_scan(void)
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@ -337,14 +349,11 @@ static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row)
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// Read columns from expander, unless it's in an error state
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if (! expander_status) {
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expander_status = i2c_start(I2C_ADDR_WRITE); if (expander_status) goto out;
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expander_status = i2c_write(EXPANDER_COL_REGISTER); if (expander_status) goto out;
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expander_status = i2c_start(I2C_ADDR_READ); if (expander_status) goto out;
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current_matrix[current_row] |= (~i2c_readNak()) & expander_input_pin_mask;
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out:
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i2c_stop();
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uint8_t state = 0;
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expander_status = i2c_readReg(I2C_ADDR, EXPANDER_COL_REGISTER, &state, 1, I2C_TIMEOUT);
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if (! expander_status) {
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current_matrix[current_row] |= (~state) & expander_input_pin_mask;
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}
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}
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// Read columns from onboard pins
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@ -366,11 +375,8 @@ static void select_row(uint8_t row) {
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if (! expander_status) {
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// set active row low : 0
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// set other rows hi-Z : 1
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expander_status = i2c_start(I2C_ADDR_WRITE); if (expander_status) goto out;
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expander_status = i2c_write(EXPANDER_ROW_REGISTER); if (expander_status) goto out;
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expander_status = i2c_write(0xFF & ~(1<<row)); if (expander_status) goto out;
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out:
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i2c_stop();
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uint8_t port = 0xFF & ~(1<<row);
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expander_status = i2c_writeReg(I2C_ADDR, EXPANDER_ROW_REGISTER, &port, 1, I2C_TIMEOUT);
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}
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// select on teensy
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@ -426,13 +432,7 @@ static bool read_rows_on_col(matrix_row_t current_matrix[], uint8_t current_col)
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return false;
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}
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expander_status = i2c_start(I2C_ADDR_WRITE); if (expander_status) goto out;
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expander_status = i2c_write(EXPANDER_ROW_REGISTER); if (expander_status) goto out;
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expander_status = i2c_start(I2C_ADDR_READ); if (expander_status) goto out;
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column_state = i2c_readNak();
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out:
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i2c_stop();
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expander_status = i2c_readReg(I2C_ADDR, EXPANDER_ROW_REGISTER, &column_state, 1, I2C_TIMEOUT);
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column_state = ~column_state;
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} else {
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@ -476,11 +476,8 @@ static void select_col(uint8_t col)
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} else {
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// set active col low : 0
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// set other cols hi-Z : 1
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expander_status = i2c_start(I2C_ADDR_WRITE); if (expander_status) goto out;
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expander_status = i2c_write(EXPANDER_COL_REGISTER); if (expander_status) goto out;
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expander_status = i2c_write(0xFF & ~(1<<col)); if (expander_status) goto out;
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out:
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i2c_stop();
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uint8_t port = 0xFF & ~(1<<col);
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expander_status = i2c_writeReg(I2C_ADDR, EXPANDER_COL_REGISTER, &port, 1, I2C_TIMEOUT);
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}
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} else {
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// select on teensy
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@ -28,5 +28,5 @@ SLEEP_LED_ENABLE = no
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RGBLIGHT_ENABLE = no
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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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@ -1,207 +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;
|
||||
|
||||
// send device address
|
||||
TWDR = address;
|
||||
TWCR = (1<<TWINT) | (1<<TWEN);
|
||||
|
||||
// wail until transmission completed and ACK/NACK has been received
|
||||
while(!(TWCR & (1<<TWINT)));
|
||||
|
||||
// check value of TWI Status Register. Mask prescaler bits.
|
||||
twst = TW_STATUS & 0xF8;
|
||||
if ( (twst != TW_MT_SLA_ACK) && (twst != TW_MR_SLA_ACK) ) return 1;
|
||||
|
||||
return 0;
|
||||
|
||||
}/* i2c_start */
|
||||
|
||||
|
||||
/*************************************************************************
|
||||
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;
|
||||
}
|
||||
//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 */
|
||||
Loading…
Reference in a new issue