644 lines
13 KiB
C
644 lines
13 KiB
C
/*
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u8g_com_i2c.c
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generic i2c interface
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Universal 8bit Graphics Library
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Copyright (c) 2011, olikraus@gmail.com
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All rights reserved.
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Redistribution and use in source and binary forms, with or without modification,
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are permitted provided that the following conditions are met:
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* Redistributions of source code must retain the above copyright notice, this list
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of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above copyright notice, this
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list of conditions and the following disclaimer in the documentation and/or other
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materials provided with the distribution.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
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CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
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INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
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CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
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ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include "u8g.h"
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//#define U8G_I2C_WITH_NO_ACK
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static uint8_t u8g_i2c_err_code;
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static uint8_t u8g_i2c_opt; /* U8G_I2C_OPT_NO_ACK, SAM: U8G_I2C_OPT_DEV_1 */
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/*
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position values
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1: start condition
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2: sla transfer
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*/
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static uint8_t u8g_i2c_err_pos;
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void u8g_i2c_clear_error(void)
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{
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u8g_i2c_err_code = U8G_I2C_ERR_NONE;
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u8g_i2c_err_pos = 0;
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}
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uint8_t u8g_i2c_get_error(void)
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{
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return u8g_i2c_err_code;
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}
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uint8_t u8g_i2c_get_err_pos(void)
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{
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return u8g_i2c_err_pos;
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}
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#if defined(__AVR__)
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static void u8g_i2c_set_error(uint8_t code, uint8_t pos)
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{
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if ( u8g_i2c_err_code > 0 )
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return;
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u8g_i2c_err_code |= code;
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u8g_i2c_err_pos = pos;
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}
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#define U8G_ATMEGA_HW_TWI
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/* remove the definition for attiny */
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#if __AVR_ARCH__ == 2
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#undef U8G_ATMEGA_HW_TWI
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#endif
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#if __AVR_ARCH__ == 25
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#undef U8G_ATMEGA_HW_TWI
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#endif
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#endif
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#if defined(U8G_ATMEGA_HW_TWI)
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#include <avr/io.h>
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#include <util/twi.h>
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void u8g_i2c_init(uint8_t options)
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{
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/*
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TWBR: bit rate register
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TWSR: status register (contains preselector bits)
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prescalar
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0 1
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1 4
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2 16
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3 64
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f = F_CPU/(16+2*TWBR*prescalar)
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F_CPU = 16MHz
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TWBR = 152;
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TWSR = 0;
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--> 50KHz
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TWBR = 72;
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TWSR = 0;
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--> 100KHz
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TWBR = 12;
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TWSR = 0;
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--> 400KHz
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F_CPU/(2*100000)-8 --> calculate TWBR value for 100KHz
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*/
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u8g_i2c_opt = options;
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TWSR = 0;
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if ( options & U8G_I2C_OPT_FAST )
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{
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TWBR = F_CPU/(2*400000)-8;
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}
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else
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{
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TWBR = F_CPU/(2*100000)-8;
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}
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u8g_i2c_clear_error();
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}
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uint8_t u8g_i2c_wait(uint8_t mask, uint8_t pos)
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{
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volatile uint16_t cnt = 2000; /* timout value should be > 280 for 50KHz Bus and 16 Mhz CPU, however the start condition might need longer */
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while( !(TWCR & mask) )
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{
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if ( cnt == 0 )
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{
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if ( u8g_i2c_opt & U8G_I2C_OPT_NO_ACK )
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{
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return 1; /* all ok */
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}
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else
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{
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u8g_i2c_set_error(U8G_I2C_ERR_TIMEOUT, pos);
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return 0; /* error */
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}
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}
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cnt--;
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}
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return 1; /* all ok */
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}
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/* sla includes all 8 bits (with r/w bit), assums master transmit */
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uint8_t u8g_i2c_start(uint8_t sla)
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{
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register uint8_t status;
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/* send start */
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TWCR = _BV(TWINT) | _BV(TWSTA) | _BV(TWEN);
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/* wait */
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if ( u8g_i2c_wait(_BV(TWINT), 1) == 0 )
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return 0;
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status = TW_STATUS;
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/* check status after start */
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if ( status != TW_START && status != TW_REP_START )
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{
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u8g_i2c_set_error(U8G_I2C_ERR_BUS, 1);
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return 0;
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}
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/* set slave address */
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TWDR = sla;
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/* enable sla transfer */
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TWCR = _BV(TWINT) | _BV(TWEN);
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/* wait */
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if ( u8g_i2c_wait(_BV(TWINT), 2) == 0 )
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return 0;
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if ( u8g_i2c_opt & U8G_I2C_OPT_NO_ACK )
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{
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/* do not check for ACK */
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}
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else
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{
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status = TW_STATUS;
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/* check status after sla */
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if ( status != TW_MT_SLA_ACK )
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{
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u8g_i2c_set_error(U8G_I2C_ERR_BUS, 2);
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return 0;
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}
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}
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return 1;
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}
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uint8_t u8g_i2c_send_byte(uint8_t data)
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{
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register uint8_t status;
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TWDR = data;
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TWCR = _BV(TWINT) | _BV(TWEN);
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if ( u8g_i2c_wait(_BV(TWINT), 3) == 0 )
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return 0;
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if ( u8g_i2c_opt & U8G_I2C_OPT_NO_ACK )
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{
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/* do not check for ACK */
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}
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else
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{
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status = TW_STATUS;
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if ( status != TW_MT_DATA_ACK )
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{
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u8g_i2c_set_error(U8G_I2C_ERR_BUS, 3);
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return 0;
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}
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}
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return 1;
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}
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void u8g_i2c_stop(void)
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{
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/* write stop */
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TWCR = _BV(TWINT) | _BV(TWEN) | _BV(TWSTO);
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/* no error is checked for the stop condition */
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u8g_i2c_wait(_BV(TWSTO), 4);
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}
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/*
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void twi_send(uint8_t adr, uint8_t data1, uint8_t data2)
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{
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u8g_i2c_start(adr<<1);
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u8g_i2c_send_byte(data1);
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u8g_i2c_send_byte(data2);
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u8g_i2c_stop();
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}
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*/
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#elif defined(ARDUINO) && defined(__SAM3X8E__)
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/* Arduino Due */
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#include "Arduino.h"
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#include "sam.h"
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/*
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Controller
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TWI0 TWCK0 PA18 A DUE PCB: SCL1
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TWI0 TWD0 PA17 A DUE PCB: SDA1
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TWI1 TWCK1 PB13 A DUE PCB: SCL 21
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TWI1 TWD1 PB12 A DUE PCB: SDA 20
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Arduino definitions
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#define PIN_WIRE_SDA (20u)
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#define PIN_WIRE_SCL (21u)
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#define WIRE_INTERFACE TWI1
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#define WIRE_INTERFACE_ID ID_TWI1
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#define WIRE_ISR_HANDLER TWI1_Handler
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#define PIN_WIRE1_SDA (70u)
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#define PIN_WIRE1_SCL (71u)
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#define WIRE1_INTERFACE TWI0
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#define WIRE1_INTERFACE_ID ID_TWI0
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#define WIRE1_ISR_HANDLER TWI0_Handler
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*/
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static void i2c_400KHz_delay(void)
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{
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/* should be at least 4 */
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/* should be 5 for 100KHz transfer speed */
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/*
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Arduino Due
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0x NOP: 470KHz
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4x NOP: 450KHz
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8x NOP: 430KHz
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16x NOP: 400KHz
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*/
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__NOP();
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__NOP();
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__NOP();
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__NOP();
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__NOP();
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__NOP();
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__NOP();
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__NOP();
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__NOP();
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__NOP();
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__NOP();
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__NOP();
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__NOP();
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__NOP();
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__NOP();
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__NOP();
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}
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static void i2c_100KHz_delay(void)
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{
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/*
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1x u8g_MicroDelay() ca. 130KHz
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2x u8g_MicroDelay() ca. 80KHz
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*/
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u8g_MicroDelay();
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u8g_MicroDelay();
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}
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uint32_t i2c_started = 0;
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uint32_t i2c_scl_pin = 0;
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uint32_t i2c_sda_pin = 0;
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void (*i2c_delay)(void) = i2c_100KHz_delay;
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const PinDescription *i2c_scl_pin_desc;
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const PinDescription *i2c_sda_pin_desc;
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/* maybe this can be optimized */
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static void i2c_init(void)
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{
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i2c_sda_pin_desc = &(g_APinDescription[i2c_sda_pin]);
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i2c_scl_pin_desc = &(g_APinDescription[i2c_scl_pin]);
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pinMode(i2c_sda_pin, OUTPUT);
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digitalWrite(i2c_sda_pin, HIGH);
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pinMode(i2c_scl_pin, OUTPUT);
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digitalWrite(i2c_scl_pin, HIGH);
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PIO_Configure( i2c_sda_pin_desc->pPort, PIO_OUTPUT_0, i2c_sda_pin_desc->ulPin, PIO_OPENDRAIN );
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PIO_Configure( i2c_scl_pin_desc->pPort, PIO_OUTPUT_0, i2c_scl_pin_desc->ulPin, PIO_OPENDRAIN );
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PIO_Clear( i2c_sda_pin_desc->pPort, i2c_sda_pin_desc->ulPin) ;
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PIO_Clear( i2c_scl_pin_desc->pPort, i2c_scl_pin_desc->ulPin) ;
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PIO_Configure( i2c_sda_pin_desc->pPort, PIO_INPUT, i2c_sda_pin_desc->ulPin, PIO_DEFAULT ) ;
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PIO_Configure( i2c_scl_pin_desc->pPort, PIO_INPUT, i2c_scl_pin_desc->ulPin, PIO_DEFAULT ) ;
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i2c_delay();
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}
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/* actually, the scl line is not observed, so this procedure does not return a value */
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static void i2c_read_scl_and_delay(void)
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{
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uint32_t dwMask = i2c_scl_pin_desc->ulPin;
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//PIO_Configure( i2c_scl_pin_desc->pPort, PIO_INPUT, i2c_scl_pin_desc->ulPin, PIO_DEFAULT ) ;
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//PIO_SetInput( i2c_scl_pin_desc->pPort, i2c_scl_pin_desc->ulPin, PIO_DEFAULT ) ;
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/* set as input */
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i2c_scl_pin_desc->pPort->PIO_ODR = dwMask ;
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i2c_scl_pin_desc->pPort->PIO_PER = dwMask ;
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i2c_delay();
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}
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static void i2c_clear_scl(void)
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{
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uint32_t dwMask = i2c_scl_pin_desc->ulPin;
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/* set open collector and drive low */
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//PIO_Configure( i2c_scl_pin_desc->pPort, PIO_OUTPUT_0, i2c_scl_pin_desc->ulPin, PIO_OPENDRAIN );
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//PIO_SetOutput( i2c_scl_pin_desc->pPort, i2c_scl_pin_desc->ulPin, 0, 1, 0);
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/* open drain, zero default output */
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i2c_scl_pin_desc->pPort->PIO_MDER = dwMask;
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i2c_scl_pin_desc->pPort->PIO_CODR = dwMask;
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i2c_scl_pin_desc->pPort->PIO_OER = dwMask;
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i2c_scl_pin_desc->pPort->PIO_PER = dwMask;
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//PIO_Clear( i2c_scl_pin_desc->pPort, i2c_scl_pin_desc->ulPin) ;
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}
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static uint8_t i2c_read_sda(void)
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{
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uint32_t dwMask = i2c_sda_pin_desc->ulPin;
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//PIO_Configure( i2c_sda_pin_desc->pPort, PIO_INPUT, i2c_sda_pin_desc->ulPin, PIO_DEFAULT ) ;
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//PIO_SetInput( i2c_sda_pin_desc->pPort, i2c_sda_pin_desc->ulPin, PIO_DEFAULT ) ;
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/* set as input */
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i2c_sda_pin_desc->pPort->PIO_ODR = dwMask ;
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i2c_sda_pin_desc->pPort->PIO_PER = dwMask ;
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return 1;
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}
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static void i2c_clear_sda(void)
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{
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uint32_t dwMask = i2c_sda_pin_desc->ulPin;
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/* set open collector and drive low */
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//PIO_Configure( i2c_sda_pin_desc->pPort, PIO_OUTPUT_0, i2c_sda_pin_desc->ulPin, PIO_OPENDRAIN );
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//PIO_SetOutput( i2c_sda_pin_desc->pPort, i2c_sda_pin_desc->ulPin, 0, 1, 0);
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/* open drain, zero default output */
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i2c_sda_pin_desc->pPort->PIO_MDER = dwMask ;
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i2c_sda_pin_desc->pPort->PIO_CODR = dwMask ;
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i2c_sda_pin_desc->pPort->PIO_OER = dwMask ;
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i2c_sda_pin_desc->pPort->PIO_PER = dwMask ;
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//PIO_Clear( i2c_sda_pin_desc->pPort, i2c_sda_pin_desc->ulPin) ;
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}
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static void i2c_start(void)
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{
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if ( i2c_started != 0 )
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{
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/* if already started: do restart */
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i2c_read_sda(); /* SDA = 1 */
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i2c_delay();
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i2c_read_scl_and_delay();
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}
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i2c_read_sda();
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/*
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if (i2c_read_sda() == 0)
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{
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// do something because arbitration is lost
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}
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*/
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/* send the start condition, both lines go from 1 to 0 */
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i2c_clear_sda();
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i2c_delay();
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i2c_clear_scl();
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i2c_started = 1;
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}
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static void i2c_stop(void)
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{
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/* set SDA to 0 */
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i2c_clear_sda();
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i2c_delay();
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/* now release all lines */
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i2c_read_scl_and_delay();
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/* set SDA to 1 */
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i2c_read_sda();
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i2c_delay();
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i2c_started = 0;
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}
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static void i2c_write_bit(uint8_t val)
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{
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if (val)
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i2c_read_sda();
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else
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i2c_clear_sda();
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i2c_delay();
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i2c_read_scl_and_delay();
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i2c_clear_scl();
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}
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static uint8_t i2c_read_bit(void)
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{
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uint8_t val;
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/* do not drive SDA */
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i2c_read_sda();
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i2c_delay();
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i2c_read_scl_and_delay();
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val = i2c_read_sda();
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i2c_delay();
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i2c_clear_scl();
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return val;
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}
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static uint8_t i2c_write_byte(uint8_t b)
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{
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i2c_write_bit(b & 128);
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i2c_write_bit(b & 64);
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i2c_write_bit(b & 32);
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i2c_write_bit(b & 16);
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i2c_write_bit(b & 8);
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i2c_write_bit(b & 4);
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i2c_write_bit(b & 2);
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i2c_write_bit(b & 1);
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/* read ack from client */
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/* 0: ack was given by client */
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/* 1: nothing happend during ack cycle */
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return i2c_read_bit();
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}
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void u8g_i2c_init(uint8_t options)
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{
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u8g_i2c_opt = options;
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u8g_i2c_clear_error();
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if ( u8g_i2c_opt & U8G_I2C_OPT_FAST )
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{
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i2c_delay = i2c_400KHz_delay;
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}
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else
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{
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i2c_delay = i2c_100KHz_delay;
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|
}
|
|
|
|
|
|
if ( u8g_i2c_opt & U8G_I2C_OPT_DEV_1 )
|
|
{
|
|
i2c_scl_pin = PIN_WIRE1_SCL;
|
|
i2c_sda_pin = PIN_WIRE1_SDA;
|
|
|
|
//REG_PIOA_PDR = PIO_PB12A_TWD1 | PIO_PB13A_TWCK1;
|
|
}
|
|
else
|
|
{
|
|
|
|
i2c_scl_pin = PIN_WIRE_SCL;
|
|
i2c_sda_pin = PIN_WIRE_SDA;
|
|
|
|
//REG_PIOA_PDR = PIO_PA17A_TWD0 | PIO_PA18A_TWCK0;
|
|
}
|
|
|
|
i2c_init();
|
|
|
|
}
|
|
|
|
/* sla includes also the r/w bit */
|
|
uint8_t u8g_i2c_start(uint8_t sla)
|
|
{
|
|
i2c_start();
|
|
i2c_write_byte(sla);
|
|
return 1;
|
|
}
|
|
|
|
uint8_t u8g_i2c_send_byte(uint8_t data)
|
|
{
|
|
return i2c_write_byte(data);
|
|
}
|
|
|
|
void u8g_i2c_stop(void)
|
|
{
|
|
i2c_stop();
|
|
}
|
|
|
|
|
|
#elif defined(U8G_RASPBERRY_PI)
|
|
|
|
#include <wiringPi.h>
|
|
#include <wiringPiI2C.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <errno.h>
|
|
|
|
#define I2C_SLA 0x3c
|
|
|
|
static int fd=-1;
|
|
static uint8_t i2cMode = 0;
|
|
|
|
void u8g_i2c_init(uint8_t options) {
|
|
u8g_i2c_clear_error();
|
|
u8g_i2c_opt = options;
|
|
|
|
if (wiringPiSetup() == -1) {
|
|
printf("wiringPi-Error\n");
|
|
exit(1);
|
|
}
|
|
|
|
fd = wiringPiI2CSetup(I2C_SLA);
|
|
if (fd < 0) {
|
|
printf ("Unable to open I2C device 0: %s\n", strerror (errno)) ;
|
|
exit (1) ;
|
|
}
|
|
//u8g_SetPIOutput(u8g, U8G_PI_RESET);
|
|
//u8g_SetPIOutput(u8g, U8G_PI_A0);
|
|
}
|
|
uint8_t u8g_i2c_start(uint8_t sla) {
|
|
u8g_i2c_send_mode(0);
|
|
|
|
return 1;
|
|
}
|
|
|
|
void u8g_i2c_stop(void) {
|
|
}
|
|
|
|
uint8_t u8g_i2c_send_mode(uint8_t mode) {
|
|
i2cMode = mode;
|
|
}
|
|
|
|
uint8_t u8g_i2c_send_byte(uint8_t data) {
|
|
wiringPiI2CWriteReg8(fd, i2cMode, data);
|
|
|
|
return 1;
|
|
}
|
|
|
|
uint8_t u8g_i2c_wait(uint8_t mask, uint8_t pos)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
#else
|
|
|
|
/* empty interface */
|
|
|
|
void u8g_i2c_init(uint8_t options)
|
|
{
|
|
u8g_i2c_clear_error();
|
|
}
|
|
|
|
uint8_t u8g_i2c_wait(uint8_t mask, uint8_t pos)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
uint8_t u8g_i2c_start(uint8_t sla)
|
|
{
|
|
return 1;
|
|
}
|
|
uint8_t u8g_i2c_send_byte(uint8_t data)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
void u8g_i2c_stop(void)
|
|
{
|
|
}
|
|
|
|
|
|
#endif
|
|
|