103 lines
2.4 KiB
C
103 lines
2.4 KiB
C
|
/** @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;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**@}*/
|
||
|
|
|