WebSVN – svnkaklik – Diff – /programy/C/avr/SFR08/i2c.c


 
/****************************************************************************
 Title	:   C  file for the I2C FUNCTIONS library (i2c.c)
 Author:    Chris efstathiou hendrix@otenet.gr
 Date:	    13/Jul/2002
 Software:  AVR-GCC with AVR-AS
 Target:    any AVR device
 Comments:  This software is FREE.
 
*****************************************************************************/
 
#include <io.h>
#include "i2c.h"
 
#ifndef CONCAT1
#define CONCAT1(a, b) CONCAT2(a, b)
#endif
 
#ifndef CONCAT2
#define CONCAT2(a, b) a ## b
#endif
 
 
/* Conversion of microseconds to the right value for the delay function */
#define I2C_DELAY	   ( (I2C_DELAY_TIME*(F_CPU/60000))/100 )  
#define I2C_TIMEOUT	   ( (I2C_TIMEOUT_TIME*(F_CPU/60000))/100 ) 
 
/* Register name forming */
#define I2C_SDA_OUT_REG   CONCAT1(PORT, I2C_SDA_PORT)
#define I2C_SCL_OUT_REG   CONCAT1(PORT, I2C_SCL_PORT)
#define I2C_SDA_DDR_REG   CONCAT1(DDR, I2C_SDA_PORT)
#define I2C_SCL_DDR_REG   CONCAT1(DDR, I2C_SCL_PORT)
#define I2C_SDA_PIN_REG   CONCAT1(PIN, I2C_SDA_PORT)
#define I2C_SCL_PIN_REG   CONCAT1(PIN, I2C_SCL_PORT)
 
/* Conversion of microseconds to the right value for the delay function */
#define I2C_DELAY	  ( (I2C_DELAY_TIME*(F_CPU/60000))/100 )  
#define I2C_TIMEOUT	  ( (I2C_TIMEOUT_TIME*(F_CPU/60000))/100 ) 
 
/* Pin states */
#define SCL_1() 	  cbi(I2C_SCL_DDR_REG, SCL_PIN)
#define SCL_0() 	  sbi(I2C_SCL_DDR_REG, SCL_PIN)
#define SDA_1() 	  cbi(I2C_SDA_DDR_REG, SDA_PIN)
#define SDA_0() 	  sbi(I2C_SDA_DDR_REG, SDA_PIN)
 
#define RELEASE_I2C_BUS() { SCL_1(); SDA_1(); }
 
/*#################################################################################################*/
 
static void delay(unsigned long us)
{
 
   while ( us ) { us--; }  /* 6 cpu cycles per loop */
 
}
/*#################################################################################################*/
 
void i2c_init(void)
{
	cbi(I2C_SDA_OUT_REG, SDA_PIN);
	cbi(I2C_SCL_OUT_REG, SCL_PIN);
	RELEASE_I2C_BUS();
	delay(I2C_TIMEOUT);
	i2c_start();
	delay(I2C_TIMEOUT);
	i2c_stop();
	delay(I2C_TIMEOUT);
 
 
return;
}
/*#################################################################################################*/
 
void i2c_start(void)
{
	RELEASE_I2C_BUS();
	delay(I2C_DELAY);
	SDA_0();
	delay(I2C_DELAY);
	SCL_0();
	delay(I2C_DELAY);
 
return;
}
/*#################################################################################################*/
 
void i2c_stop(void)
{
	SDA_0();
	SCL_1();
	delay(I2C_DELAY);
	SDA_1();
	delay(I2C_DELAY);
	SCL_0();
	delay(I2C_DELAY);
 
return;
}
/*#################################################################################################*/
 
unsigned char i2c_transmit(unsigned char data)
{
register unsigned char bit=0;
 
	for(bit=0; bit<=7; bit++)
	  {
	      if( data & 0x80 ) { SDA_1(); } else { SDA_0(); }
	      SCL_1();
	      delay(I2C_DELAY);
	      SCL_0();
	      delay(I2C_DELAY);
	      data = (data<<1);
	  }
	/* Look for AKNOWLEDGE */
	RELEASE_I2C_BUS();
	delay(I2C_DELAY);
 
 
	if( bit_is_clear(I2C_SDA_PIN_REG, SDA_PIN) )
	 {
	     SCL_0();
	     delay(I2C_DELAY);
	 }
	else{
		 delay(I2C_TIMEOUT);
		 if( bit_is_clear(I2C_SDA_PIN_REG, SDA_PIN) )
		  {
		     SCL_0();
		     delay(I2C_DELAY);
		  }
		 else { return(I2C_ERROR_DEVICE_NOT_RESPONDING); }
	    }
 
 
	if( bit_is_clear(I2C_SDA_PIN_REG, SDA_PIN) ) 
	 { 
	       delay(I2C_TIMEOUT);
	       if( bit_is_clear(I2C_SDA_PIN_REG, SDA_PIN) ) { return(I2C_ERROR_DEVICE_BUSY); }
	 }   
 
 
return(I2C_NO_ERROR);	  
}
/*#################################################################################################*/
 
unsigned char i2c_receive(unsigned char ack)
{
register unsigned char bit=0, data=0;
 
	SDA_1();
	for(bit=0; bit<=7; bit++)
	  {
	      SCL_1();
	      delay(I2C_DELAY);
	      data = (data<<1);
	      if( bit_is_set(I2C_SDA_PIN_REG, SDA_PIN) ) { data++; }
	      SCL_0();
	      delay(I2C_DELAY);
	  }
	
	/* if CONTINUE then send AKNOWLEDGE else if QUIT do not send AKNOWLEDGE (send Nack) */	     
	if(ack==I2C_CONTINUE) { SDA_0(); }  else { SDA_1(); }
	SCL_1();
	delay(I2C_DELAY);
	SCL_0();
	delay(I2C_DELAY);
 
return data;
}
/*#################################################################################################*/
 
 

Rev 409	Rev 410
1		1
2	`/****************************************************************************`	2	`/****************************************************************************`
3	`Title : C file for the I2C FUNCTIONS library (i2c.c)`	3	`Title : C file for the I2C FUNCTIONS library (i2c.c)`
4	`Author: Chris efstathiou hendrix@otenet.gr`	4	`Author: Chris efstathiou hendrix@otenet.gr`
5	`Date: 13/Jul/2002`	5	`Date: 13/Jul/2002`
6	`Software: AVR-GCC with AVR-AS`	6	`Software: AVR-GCC with AVR-AS`
7	`Target: any AVR device`	7	`Target: any AVR device`
8	`Comments: This software is FREE.`	8	`Comments: This software is FREE.`
9		9
10	`*****************************************************************************/`	10	`*****************************************************************************/`
11		11
12	`#include <io.h>`	12	`#include <io.h>`
13	`#include "i2c.h"`	13	`#include "i2c.h"`
14		14
15	`#ifndef CONCAT1`	15	`#ifndef CONCAT1`
16	`#define CONCAT1(a, b) CONCAT2(a, b)`	16	`#define CONCAT1(a, b) CONCAT2(a, b)`
17	`#endif`	17	`#endif`
18		18
19	`#ifndef CONCAT2`	19	`#ifndef CONCAT2`
20	`#define CONCAT2(a, b) a ## b`	20	`#define CONCAT2(a, b) a ## b`
21	`#endif`	21	`#endif`
22		22
23		23
24	`/* Conversion of microseconds to the right value for the delay function */`	24	`/* Conversion of microseconds to the right value for the delay function */`
25	`#define I2C_DELAY ( (I2C_DELAY_TIME*(F_CPU/60000))/100 )`	25	`#define I2C_DELAY ( (I2C_DELAY_TIME*(F_CPU/60000))/100 )`
26	`#define I2C_TIMEOUT ( (I2C_TIMEOUT_TIME*(F_CPU/60000))/100 )`	26	`#define I2C_TIMEOUT ( (I2C_TIMEOUT_TIME*(F_CPU/60000))/100 )`
27		27
28	`/* Register name forming */`	28	`/* Register name forming */`
29	`#define I2C_SDA_OUT_REG CONCAT1(PORT, I2C_SDA_PORT)`	29	`#define I2C_SDA_OUT_REG CONCAT1(PORT, I2C_SDA_PORT)`
30	`#define I2C_SCL_OUT_REG CONCAT1(PORT, I2C_SCL_PORT)`	30	`#define I2C_SCL_OUT_REG CONCAT1(PORT, I2C_SCL_PORT)`
31	`#define I2C_SDA_DDR_REG CONCAT1(DDR, I2C_SDA_PORT)`	31	`#define I2C_SDA_DDR_REG CONCAT1(DDR, I2C_SDA_PORT)`
32	`#define I2C_SCL_DDR_REG CONCAT1(DDR, I2C_SCL_PORT)`	32	`#define I2C_SCL_DDR_REG CONCAT1(DDR, I2C_SCL_PORT)`
33	`#define I2C_SDA_PIN_REG CONCAT1(PIN, I2C_SDA_PORT)`	33	`#define I2C_SDA_PIN_REG CONCAT1(PIN, I2C_SDA_PORT)`
34	`#define I2C_SCL_PIN_REG CONCAT1(PIN, I2C_SCL_PORT)`	34	`#define I2C_SCL_PIN_REG CONCAT1(PIN, I2C_SCL_PORT)`
35		35
36	`/* Conversion of microseconds to the right value for the delay function */`	36	`/* Conversion of microseconds to the right value for the delay function */`
37	`#define I2C_DELAY ( (I2C_DELAY_TIME*(F_CPU/60000))/100 )`	37	`#define I2C_DELAY ( (I2C_DELAY_TIME*(F_CPU/60000))/100 )`
38	`#define I2C_TIMEOUT ( (I2C_TIMEOUT_TIME*(F_CPU/60000))/100 )`	38	`#define I2C_TIMEOUT ( (I2C_TIMEOUT_TIME*(F_CPU/60000))/100 )`
39		39
40	`/* Pin states */`	40	`/* Pin states */`
41	`#define SCL_1() cbi(I2C_SCL_DDR_REG, SCL_PIN)`	41	`#define SCL_1() cbi(I2C_SCL_DDR_REG, SCL_PIN)`
42	`#define SCL_0() sbi(I2C_SCL_DDR_REG, SCL_PIN)`	42	`#define SCL_0() sbi(I2C_SCL_DDR_REG, SCL_PIN)`
43	`#define SDA_1() cbi(I2C_SDA_DDR_REG, SDA_PIN)`	43	`#define SDA_1() cbi(I2C_SDA_DDR_REG, SDA_PIN)`
44	`#define SDA_0() sbi(I2C_SDA_DDR_REG, SDA_PIN)`	44	`#define SDA_0() sbi(I2C_SDA_DDR_REG, SDA_PIN)`
45		45
46	`#define RELEASE_I2C_BUS() { SCL_1(); SDA_1(); }`	46	`#define RELEASE_I2C_BUS() { SCL_1(); SDA_1(); }`
47		47
48	`/#################################################################################################/`	48	`/#################################################################################################/`
49		49
50	`static void delay(unsigned long us)`	50	`static void delay(unsigned long us)`
51	`{`	51	`{`
52		52
53	`while ( us ) { us--; } /* 6 cpu cycles per loop */`	53	`while ( us ) { us--; } /* 6 cpu cycles per loop */`
54		54
55	`}`	55	`}`
56	`/#################################################################################################/`	56	`/#################################################################################################/`
57		57
58	`void i2c_init(void)`	58	`void i2c_init(void)`
59	`{`	59	`{`
60	`cbi(I2C_SDA_OUT_REG, SDA_PIN);`	60	`cbi(I2C_SDA_OUT_REG, SDA_PIN);`
61	`cbi(I2C_SCL_OUT_REG, SCL_PIN);`	61	`cbi(I2C_SCL_OUT_REG, SCL_PIN);`
62	`RELEASE_I2C_BUS();`	62	`RELEASE_I2C_BUS();`
63	`delay(I2C_TIMEOUT);`	63	`delay(I2C_TIMEOUT);`
64	`i2c_start();`	64	`i2c_start();`
65	`delay(I2C_TIMEOUT);`	65	`delay(I2C_TIMEOUT);`
66	`i2c_stop();`	66	`i2c_stop();`
67	`delay(I2C_TIMEOUT);`	67	`delay(I2C_TIMEOUT);`
68		68
69		69
70	`return;`	70	`return;`
71	`}`	71	`}`
72	`/#################################################################################################/`	72	`/#################################################################################################/`
73		73
74	`void i2c_start(void)`	74	`void i2c_start(void)`
75	`{`	75	`{`
76	`RELEASE_I2C_BUS();`	76	`RELEASE_I2C_BUS();`
77	`delay(I2C_DELAY);`	77	`delay(I2C_DELAY);`
78	`SDA_0();`	78	`SDA_0();`
79	`delay(I2C_DELAY);`	79	`delay(I2C_DELAY);`
80	`SCL_0();`	80	`SCL_0();`
81	`delay(I2C_DELAY);`	81	`delay(I2C_DELAY);`
82		82
83	`return;`	83	`return;`
84	`}`	84	`}`
85	`/#################################################################################################/`	85	`/#################################################################################################/`
86		86
87	`void i2c_stop(void)`	87	`void i2c_stop(void)`
88	`{`	88	`{`
89	`SDA_0();`	89	`SDA_0();`
90	`SCL_1();`	90	`SCL_1();`
91	`delay(I2C_DELAY);`	91	`delay(I2C_DELAY);`
92	`SDA_1();`	92	`SDA_1();`
93	`delay(I2C_DELAY);`	93	`delay(I2C_DELAY);`
94	`SCL_0();`	94	`SCL_0();`
95	`delay(I2C_DELAY);`	95	`delay(I2C_DELAY);`
96		96
97	`return;`	97	`return;`
98	`}`	98	`}`
99	`/#################################################################################################/`	99	`/#################################################################################################/`
100		100
101	`unsigned char i2c_transmit(unsigned char data)`	101	`unsigned char i2c_transmit(unsigned char data)`
102	`{`	102	`{`
103	`register unsigned char bit=0;`	103	`register unsigned char bit=0;`
104		104
105	`for(bit=0; bit<=7; bit++)`	105	`for(bit=0; bit<=7; bit++)`
106	`{`	106	`{`
107	`if( data & 0x80 ) { SDA_1(); } else { SDA_0(); }`	107	`if( data & 0x80 ) { SDA_1(); } else { SDA_0(); }`
108	`SCL_1();`	108	`SCL_1();`
109	`delay(I2C_DELAY);`	109	`delay(I2C_DELAY);`
110	`SCL_0();`	110	`SCL_0();`
111	`delay(I2C_DELAY);`	111	`delay(I2C_DELAY);`
112	`data = (data<<1);`	112	`data = (data<<1);`
113	`}`	113	`}`
114	`/* Look for AKNOWLEDGE */`	114	`/* Look for AKNOWLEDGE */`
115	`RELEASE_I2C_BUS();`	115	`RELEASE_I2C_BUS();`
116	`delay(I2C_DELAY);`	116	`delay(I2C_DELAY);`
117		117
118		118
119	`if( bit_is_clear(I2C_SDA_PIN_REG, SDA_PIN) )`	119	`if( bit_is_clear(I2C_SDA_PIN_REG, SDA_PIN) )`
120	`{`	120	`{`
121	`SCL_0();`	121	`SCL_0();`
122	`delay(I2C_DELAY);`	122	`delay(I2C_DELAY);`
123	`}`	123	`}`
124	`else{`	124	`else{`
125	`delay(I2C_TIMEOUT);`	125	`delay(I2C_TIMEOUT);`
126	`if( bit_is_clear(I2C_SDA_PIN_REG, SDA_PIN) )`	126	`if( bit_is_clear(I2C_SDA_PIN_REG, SDA_PIN) )`
127	`{`	127	`{`
128	`SCL_0();`	128	`SCL_0();`
129	`delay(I2C_DELAY);`	129	`delay(I2C_DELAY);`
130	`}`	130	`}`
131	`else { return(I2C_ERROR_DEVICE_NOT_RESPONDING); }`	131	`else { return(I2C_ERROR_DEVICE_NOT_RESPONDING); }`
132	`}`	132	`}`
133		133
134		134
135	`if( bit_is_clear(I2C_SDA_PIN_REG, SDA_PIN) )`	135	`if( bit_is_clear(I2C_SDA_PIN_REG, SDA_PIN) )`
136	`{`	136	`{`
137	`delay(I2C_TIMEOUT);`	137	`delay(I2C_TIMEOUT);`
138	`if( bit_is_clear(I2C_SDA_PIN_REG, SDA_PIN) ) { return(I2C_ERROR_DEVICE_BUSY); }`	138	`if( bit_is_clear(I2C_SDA_PIN_REG, SDA_PIN) ) { return(I2C_ERROR_DEVICE_BUSY); }`
139	`}`	139	`}`
140		140
141		141
142	`return(I2C_NO_ERROR);`	142	`return(I2C_NO_ERROR);`
143	`}`	143	`}`
144	`/#################################################################################################/`	144	`/#################################################################################################/`
145		145
146	`unsigned char i2c_receive(unsigned char ack)`	146	`unsigned char i2c_receive(unsigned char ack)`
147	`{`	147	`{`
148	`register unsigned char bit=0, data=0;`	148	`register unsigned char bit=0, data=0;`
149		149
150	`SDA_1();`	150	`SDA_1();`
151	`for(bit=0; bit<=7; bit++)`	151	`for(bit=0; bit<=7; bit++)`
152	`{`	152	`{`
153	`SCL_1();`	153	`SCL_1();`
154	`delay(I2C_DELAY);`	154	`delay(I2C_DELAY);`
155	`data = (data<<1);`	155	`data = (data<<1);`
156	`if( bit_is_set(I2C_SDA_PIN_REG, SDA_PIN) ) { data++; }`	156	`if( bit_is_set(I2C_SDA_PIN_REG, SDA_PIN) ) { data++; }`
157	`SCL_0();`	157	`SCL_0();`
158	`delay(I2C_DELAY);`	158	`delay(I2C_DELAY);`
159	`}`	159	`}`
160		160
161	`/* if CONTINUE then send AKNOWLEDGE else if QUIT do not send AKNOWLEDGE (send Nack) */`	161	`/* if CONTINUE then send AKNOWLEDGE else if QUIT do not send AKNOWLEDGE (send Nack) */`
162	`if(ack==I2C_CONTINUE) { SDA_0(); } else { SDA_1(); }`	162	`if(ack==I2C_CONTINUE) { SDA_0(); } else { SDA_1(); }`
163	`SCL_1();`	163	`SCL_1();`
164	`delay(I2C_DELAY);`	164	`delay(I2C_DELAY);`
165	`SCL_0();`	165	`SCL_0();`
166	`delay(I2C_DELAY);`	166	`delay(I2C_DELAY);`
167		167
168	`return data;`	168	`return data;`
169	`}`	169	`}`
170	`/#################################################################################################/`	170	`/#################################################################################################/`
171		171
172		172

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