4 * This file is part of BeRTOS.
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14 * GNU General Public License for more details.
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18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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29 * Copyright 2010 Develer S.r.l. (http://www.develer.com/)
33 * \brief STM32F103xx I2C driver.
35 * \author Daniele Basile <asterix@develer.com>
38 #include "cfg/cfg_i2c.h"
40 #define LOG_LEVEL I2C_LOG_LEVEL
41 #define LOG_FORMAT I2C_LOG_FORMAT
44 #include <cfg/debug.h>
45 #include <cfg/macros.h> // BV()
46 #include <cfg/module.h>
48 #include <drv/gpio_stm32.h>
49 #include <drv/irq_cm3.h>
50 #include <drv/clock_stm32.h>
55 struct stm32_i2c *i2c = (struct stm32_i2c *)I2C1_BASE;
58 * Send START condition on the bus.
60 * \return true on success, false otherwise.
62 static bool i2c_builtin_start(void)
64 i2c->CR1 |= CR1_START_SET;
66 return ((i2c->SR1 & (BV(SR1_BUSY) | BV(SR1_MSL))) &
67 (i2c->SR2 & BV(SR2_SB)));
72 * Send START condition and select slave for write.
73 * \c id is the device id comprehensive of address left shifted by 1.
74 * The LSB of \c id is ignored and reset to 0 for write operation.
76 * \return true on success, false otherwise.
78 bool i2c_builtin_start_w(uint8_t id)
80 id &= OAR1_ADD0_RESET;
81 while (i2c_builtin_start())
89 * Send START condition and select slave for read.
90 * \c id is the device id comprehensive of address left shifted by 1.
91 * The LSB of \c id is ignored and set to 1 for read operation.
93 * \return true on success, false otherwise.
95 bool i2c_builtin_start_r(uint8_t id)
104 * Send STOP condition.
106 void i2c_builtin_stop(void)
108 i2c->CR1 |= CR1_STOP_SET;
113 * Put a single byte in master transmitter mode
114 * to the selected slave device through the TWI bus.
116 * \return true on success, false on error.
118 bool i2c_builtin_put(const uint8_t data)
125 * Get 1 byte from slave in master transmitter mode
126 * to the selected slave device through the TWI bus.
127 * If \a ack is true issue a ACK after getting the byte,
128 * otherwise a NACK is issued.
130 * \return the byte read if ok, EOF on errors.
132 int i2c_builtin_get(bool ack)
141 * Initialize I2C module.
143 void i2c_builtin_init(void)
147 RCC->APB2ENR |= RCC_APB2_GPIOB;
148 RCC->APB1ENR |= RCC_APB1_I2C1;
150 stm32_gpioPinConfig((struct stm32_gpio *)GPIOB_BASE, GPIO_I2C1_SCL_PIN,
151 GPIO_MODE_AF_OD, GPIO_SPEED_50MHZ);
153 stm32_gpioPinConfig((struct stm32_gpio *)GPIOB_BASE, GPIO_I2C1_SDA_PIN,
154 GPIO_MODE_AF_OD, GPIO_SPEED_50MHZ);
162 i2c->CR2 |= CR2_FREQ_36MHZ;
164 /* Configure spi in standard mode */
165 #if CONFIG_I2C_FREQ <= 100000
166 i2c->TRISE |= (CR2_FREQ_36MHZ + 1);
169 #error fast mode not supported
172 i2c->CR1 |= CR1_PE_SET;
173 i2c->CR1 |= CR1_ACK_SET;