qmk

QMK Firmware
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i2c.h (1113B)


      1 #pragma once
      2 
      3 #include <stdint.h>
      4 
      5 #ifndef F_CPU
      6 #define F_CPU 16000000UL
      7 #endif
      8 
      9 #define I2C_READ 1
     10 #define I2C_WRITE 0
     11 
     12 #define I2C_ACK 1
     13 #define I2C_NACK 0
     14 
     15 #define SLAVE_BUFFER_SIZE 0x10
     16 
     17 // i2c SCL clock frequency 400kHz
     18 #define SCL_CLOCK  400000L
     19 
     20 extern volatile uint8_t i2c_slave_buffer[SLAVE_BUFFER_SIZE];
     21 
     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);
     29 
     30 
     31 static inline unsigned char i2c_start_read(unsigned char addr) {
     32   return i2c_master_start((addr << 1) | I2C_READ);
     33 }
     34 
     35 static inline unsigned char i2c_start_write(unsigned char addr) {
     36   return i2c_master_start((addr << 1) | I2C_WRITE);
     37 }
     38 
     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);
     45 
     46 #define i2c_read(ack)  (ack) ? i2c_readAck() : i2c_readNak();