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#ifndef __I2C_H
#define __I2C_H
#include "global.h"
// Definitions of I2C analog filter state
#define I2C_AF_ENABLE ((uint32_t)0x00000000U) // Analog filter is enabled
#define I2C_AF_DISABLE I2C_CR1_ANFOFF // Analog filter is disabled
// Flags definitions for transmit function
#define I2C_TX_STOP ((uint32_t)0x00000000U) // Generate STOP condition
#define I2C_TX_NOSTOP ((uint32_t)0x10000000U) // Don't generate STOP condition
#define I2C_TX_NOSTART ((uint32_t)0x20000000U) // Don't generate START condition
#define I2C_TX_CONT ((uint32_t)0x40000000U) // The transmission will be continued
// Definitions for compatibility with old code using this library
#define I2C_GENSTOP_YES I2C_TX_STOP
#define I2C_GENSTOP_NO I2C_TX_NOSTOP
// Definition of bits to reset in CR2 register
#define I2C_CR2_ALL (I2C_CR2_SADD | \
I2C_CR2_NBYTES | \
I2C_CR2_RELOAD | \
I2C_CR2_AUTOEND | \
I2C_CR2_RD_WRN | \
I2C_CR2_START | \
I2C_CR2_STOP)
// Definition of all bits in ICR register (clear all I2C flags at once)
#define I2C_ICR_ALL (I2C_ICR_ADDRCF | \
I2C_ICR_ALERTCF | \
I2C_ICR_ARLOCF | \
I2C_ICR_BERRCF | \
I2C_ICR_NACKCF | \
I2C_ICR_OVRCF | \
I2C_ICR_PECCF | \
I2C_ICR_STOPCF | \
I2C_ICR_TIMOUTCF)
// Result of I2C functions
typedef enum {
I2C_ERROR = 0,
I2C_SUCCESS = !I2C_ERROR
} i2cstatus;
// Public functions and macros
// Enable I2C peripheral
// input:
// I2Cx - pointer to the I2C peripheral (I2C1, etc.)
static inline void i2c_enable(I2C_TypeDef* I2Cx) {
I2Cx->CR1 |= I2C_CR1_PE;
}
// Disable I2C peripheral
// input:
// I2Cx - pointer to the I2C peripheral (I2C1, etc.)
static inline void i2c_disable(I2C_TypeDef* I2Cx) {
I2Cx->CR1 &= ~I2C_CR1_PE;
}
// Configure I2C noise filters
// input:
// I2Cx - pointer to the I2C peripheral (I2C1, etc.)
// af - analog filter state, I2C_AF_DISABLE or I2C_AF_ENABLE
// df - digital filter configuration, can be a value in range from 0 to 15
// zero value means the digital filter is disabled
// this values means filtering capability up to (df * ti2cclk)
// note: must be called only when I2C is disabled (PE bit in I2C_CR1 register is reset)
static inline void i2c_config_filters(I2C_TypeDef* I2Cx, uint32_t af, uint32_t df) {
I2Cx->CR1 &= ~(I2C_CR1_ANFOFF | I2C_CR1_DNF);
I2Cx->CR1 |= (af & I2C_CR1_ANFOFF) | ((df << I2C_CR1_DNF_Pos) & I2C_CR1_DNF);
}
// Configure the I2C timings (SDA setup/hold time and SCL high/low period)
// input:
// I2Cx - pointer to the I2C peripheral (I2C1, etc.)
// timing - the value for I2C_TIMINGR register
// note: must be called only when I2C is disabled (PE bit in I2C_CR1 register is reset)
static inline void i2c_config_timing(I2C_TypeDef* I2Cx, uint32_t timing) {
I2Cx->TIMINGR = timing;
}
// Generate START condition
// input:
// I2Cx - pointer to the I2C peripheral (I2C1, etc.)
// addr - I2C device address
// note: 7-bit addressing mode
static inline void i2c_genstart(I2C_TypeDef* I2Cx, uint32_t addr) {
I2Cx->CR2 = (addr & I2C_CR2_SADD) | I2C_CR2_START | I2C_CR2_AUTOEND;
}
// Generate STOP condition
// input:
// I2Cx - pointer to the I2C peripheral (I2C1, etc.)
static inline void i2c_genstop(I2C_TypeDef* I2Cx) {
I2Cx->CR2 |= I2C_CR2_STOP;
}
// Function prototypes
i2cstatus i2c_is_device_ready(I2C_TypeDef* I2Cx, uint8_t devAddr, uint32_t Trials);
i2cstatus i2c_transmit(I2C_TypeDef* I2Cx, uint8_t devAddr, const uint8_t *pBuf, uint32_t nbytes, uint32_t flags);
i2cstatus i2c_receive(I2C_TypeDef* I2Cx, uint8_t devAddr, uint8_t *pBuf, uint32_t nbytes);
#endif // __I2C_H
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