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Diffstat (limited to 'libopencm3/lib/lpc43xx/i2c.c')
| -rw-r--r-- | libopencm3/lib/lpc43xx/i2c.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/libopencm3/lib/lpc43xx/i2c.c b/libopencm3/lib/lpc43xx/i2c.c new file mode 100644 index 0000000..0d6c4c6 --- /dev/null +++ b/libopencm3/lib/lpc43xx/i2c.c @@ -0,0 +1,102 @@ +/** @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; +} + +/**@}*/ + |