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/** @defgroup i2c_file I2C
@ingroup LPC43xx
@brief <b>libopencm3 LPC43xx I2C</b>
@version 1.0.0
@author @htmlonly © @endhtmlonly 2012 Michael Ossmann <mike@ossmann.com>
LGPL License Terms @ref lgpl_license
*/
/*
* This file is part of the libopencm3 project.
*
* Copyright (C) 2012 Michael Ossmann <mike@ossmann.com>
*
* This library is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* This is a very minimal I2C driver just to make sure we can get the
* peripheral working.
*/
/**@{*/
#include <libopencm3/lpc43xx/i2c.h>
#include <libopencm3/lpc43xx/scu.h>
#include <libopencm3/lpc43xx/cgu.h>
void i2c0_init(const uint16_t duty_cycle_count)
{
/* enable input on SCL and SDA pins */
SCU_SFSI2C0 = SCU_I2C0_NOMINAL;
I2C0_SCLH = duty_cycle_count;
I2C0_SCLL = duty_cycle_count;
/* clear the control bits */
I2C0_CONCLR = (I2C_CONCLR_AAC | I2C_CONCLR_SIC
| I2C_CONCLR_STAC | I2C_CONCLR_I2ENC);
/* enable I2C0 */
I2C0_CONSET = I2C_CONSET_I2EN;
}
/* transmit start bit */
void i2c0_tx_start(void)
{
I2C0_CONCLR = I2C_CONCLR_SIC;
I2C0_CONSET = I2C_CONSET_STA;
while (!(I2C0_CONSET & I2C_CONSET_SI));
I2C0_CONCLR = I2C_CONCLR_STAC;
}
/* transmit data byte */
void i2c0_tx_byte(uint8_t byte)
{
if (I2C0_CONSET & I2C_CONSET_STA) {
I2C0_CONCLR = I2C_CONCLR_STAC;
}
I2C0_DAT = byte;
I2C0_CONCLR = I2C_CONCLR_SIC;
while (!(I2C0_CONSET & I2C_CONSET_SI));
}
/* receive data byte */
uint8_t i2c0_rx_byte(void)
{
if (I2C0_CONSET & I2C_CONSET_STA) {
I2C0_CONCLR = I2C_CONCLR_STAC;
}
I2C0_CONCLR = I2C_CONCLR_SIC;
while (!(I2C0_CONSET & I2C_CONSET_SI));
return I2C0_DAT;
}
/* transmit stop bit */
void i2c0_stop(void)
{
if (I2C0_CONSET & I2C_CONSET_STA) {
I2C0_CONCLR = I2C_CONCLR_STAC;
}
I2C0_CONSET = I2C_CONSET_STO;
I2C0_CONCLR = I2C_CONCLR_SIC;
}
/**@}*/
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