1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65

/*
 * SoftI2CMaster.h -- Multi-instance software I2C Master library
 * 
 * 2010-2012 Tod E. Kurt, http://todbot.com/blog/
 *
 */

#ifndef SoftI2CMaster_h
#define SoftI2CMaster_h

#include <inttypes.h>

#define _SOFTI2CMASTER_VERSION 12  // software version of this library


class SoftI2CMaster
{

private:
  // per object data
  uint8_t _sdaPin;
  uint8_t _sclPin;
  uint8_t _sdaBitMask;
  uint8_t _sclBitMask;
  volatile uint8_t *_sdaPortReg;
  volatile uint8_t *_sclPortReg;
  volatile uint8_t *_sdaDirReg;
  volatile uint8_t *_sclDirReg;

  boolean usePullups;

  // private methods
  void setPins(uint8_t sdaPin, uint8_t sclPin, boolean usePullups);

  void i2c_writebit( uint8_t c );
  uint8_t i2c_readbit(void);
  void i2c_init(void);
  void i2c_start(void);
  void i2c_repstart(void);
  void i2c_stop(void);
  uint8_t i2c_write( uint8_t c );
  uint8_t i2c_read( uint8_t ack );
  
public:
  // public methods
  SoftI2CMaster(uint8_t sdaPin, uint8_t sclPin);
  SoftI2CMaster(uint8_t sdaPin, uint8_t sclPin, boolean usePullups);

  uint8_t beginTransmission(uint8_t address);
  uint8_t beginTransmission(int address);
  uint8_t endTransmission(void);
  uint8_t send(uint8_t);
  void send(uint8_t*, uint8_t);
  void send(int);
  void send(char*);

  uint8_t requestFrom(int address);
  uint8_t requestFrom(uint8_t address);
  uint8_t receive( uint8_t ack );
  uint8_t receive();
  uint8_t receiveLast();

};

#endif