6 #define F_CPU 16000000UL
15 #define SLAVE_BUFFER_SIZE 0x10
17 // i2c SCL clock frequency 400kHz
18 #define SCL_CLOCK 400000L
20 extern volatile uint8_t i2c_slave_buffer[SLAVE_BUFFER_SIZE];
22 void i2c_master_init(void);
23 uint8_t i2c_master_start(uint8_t address);
24 void i2c_master_stop(void);
25 uint8_t i2c_master_write(uint8_t data);
26 uint8_t i2c_master_read(int);
27 void i2c_reset_state(void);
28 void i2c_slave_init(uint8_t address);
31 static inline unsigned char i2c_start_read(unsigned char addr) {
32 return i2c_master_start((addr << 1) | I2C_READ);
35 static inline unsigned char i2c_start_write(unsigned char addr) {
36 return i2c_master_start((addr << 1) | I2C_WRITE);
39 // from SSD1306 scrips
40 extern unsigned char i2c_rep_start(unsigned char addr);
41 extern void i2c_start_wait(unsigned char addr);
42 extern unsigned char i2c_readAck(void);
43 extern unsigned char i2c_readNak(void);
44 extern unsigned char i2c_read(unsigned char ack);
46 #define i2c_read(ack) (ack) ? i2c_readAck() : i2c_readNak();