51 lines
1.1 KiB

#ifndef I2C_H
#define I2C_H
#include <stdint.h>
#include "split_util.h"
#ifndef F_CPU
#define F_CPU 16000000UL
#endif
#define I2C_READ 1
#define I2C_WRITE 0
#define I2C_ACK 1
#define I2C_NACK 0
#define SLAVE_BUFFER_SIZE 0x10
// i2c SCL clock frequency
#define SCL_CLOCK 400000L
extern volatile uint8_t i2c_slave_buffer[SLAVE_BUFFER_SIZE];
void i2c_master_init(void);
uint8_t i2c_master_start(uint8_t address);
void i2c_master_stop(void);
uint8_t i2c_master_write(uint8_t data);
uint8_t i2c_master_read(int);
void i2c_reset_state(void);
void i2c_slave_init(uint8_t address);
static inline unsigned char i2c_start_read(unsigned char addr) {
return i2c_master_start((addr << 1) | I2C_READ);
}
static inline unsigned char i2c_start_write(unsigned char addr) {
return i2c_master_start((addr << 1) | I2C_WRITE);
}
// from SSD1306 scrips
extern unsigned char i2c_rep_start(unsigned char addr);
extern void i2c_start_wait(unsigned char addr);
extern unsigned char i2c_readAck(void);
extern unsigned char i2c_readNak(void);
extern unsigned char i2c_read(unsigned char ack);
#define i2c_read(ack) (ack) ? i2c_readAck() : i2c_readNak();
#endif