1. /*
2.  * I2C.c
3.  *
4.  * Created: 11.04.2019 08:39:07
5.  *  Author: KTM
6.  */
7.  
8. #define F_CPU 16000000L
9. #include <avr/io.h>
10. #include<util/delay.h>
11. #define EEDEVADR 0b10100000
12. #define ERROR 1
13. #define SUCCESS (!ERROR)
14.  
15.  
16. #define D7 7
17. #define D6 6
18. #define D5 5
19. #define D4 4
20. #define E 3
21. #define RS 2
22. #define RW 1
23. #define SS 2
24. #define MOSI 3
25. #define MISO 4
26. #define SCK 5
27.  
28.  
29.  
30. void lcd_4bity(unsigned char fourbits)
31. {
32.   PORTD |= (1<<E);
33.   if( fourbits & 0x01) PORTD |= (1<<D4); else PORTD &= ~(1<<D4);
34.   if( fourbits & 0x02) PORTD |= (1<<D5); else PORTD &= ~(1<<D5);
35.   if( fourbits & 0x04) PORTD |= (1<<D6); else PORTD &= ~(1<<D6);
36.   if( fourbits & 0x08) PORTD |= (1<<D7); else PORTD &= ~(1<<D7);
37.   PORTD &= ~(1<<E);
38.  
39. }
40.  
41. void lcd_bajt(unsigned char bajt)
42. {
43.   PORTD |= (1<<E);
44.   lcd_4bity(bajt>>4);
45.   PORTD &= ~(1<<E);
46.   _delay_us(5);
47.   PORTD |= (1<<E);
48.   lcd_4bity(bajt);
49.   PORTD &= ~(1<<E);
50.   _delay_ms(1);
51.  
52. }
53.  
54.  
55. void ini_lcd(void)
56. {
57.   lcd_4bity(3);
58.   _delay_ms(10);
59.   lcd_4bity(3);
60.   _delay_ms(1);
61.   lcd_4bity(3);
62.   _delay_ms(1);
63.   lcd_4bity(2);
64.   _delay_ms(1);
65.  
66.   lcd_bajt(28);
67.   _delay_ms(1);
68.   lcd_bajt(20);
69.   _delay_ms(1);
70.   lcd_bajt(12);
71.   _delay_ms(1);
72.   lcd_bajt(6);
73.   _delay_ms(1);
74.   lcd_bajt(1);
75.   _delay_ms(10);
76.   lcd_bajt(128);
77.   _delay_ms(5);
78.  
79.  
80. }
81.  
82. char aData;
83. char bData;
84.  
85. void SPI_Init(void)
86. {
87.   DDRB |= (1<<SS);
88.   PORTB &= ~(1<<SS);
89.   /* Set MOSI and SCK output, all others input */
90.   DDRB |= (1<<MOSI)|(1<<SCK);
91.   PORTB |= (1<<MISO);
92.   /* Enable SPI, Master, set clock rate fck/16 */
93.   SPCR |= (1<<SPE)|(1<<MSTR)|(1<<SPR1)|(1<<CPHA);
94.  
95. }
96.  
97. char SPI_Transmit(char aData, char bData)
98. {
99.   PORTB |= (1<<SS);
100.   /* Start transmission */
101.   SPDR = aData;
102.   /* Wait for transmission complete */
103.   while(!(SPSR & (1<<SPIF)));
104.   SPDR = bData;
105.   /* Wait for transmission complete */
106.   while(!(SPSR & (1<<SPIF)));
107.   PORTB &= ~(1<<SS);
108.   char z = SPDR;
109.   return(z);
110. }
111.  
112. void setup(void)
113. {
114.   DDRD |= (1<<D7);
115.   DDRD |= (1<<D6);
116.   DDRD |= (1<<D5);
117.   DDRD |= (1<<D4);
118.   DDRD |= (1<<E);
119.   DDRD |= (1<<RS);
120.   DDRD |= (1<<RW);
121.   PORTD &= ~(1<<RW);
122.   PORTD &= ~(1<<RS);  
123.   PORTD &= ~(1<<E);
124.   ini_lcd();
125.   PORTD |= (1<<RS);
126.   _delay_ms(1);
127.  
128. }
129.  
130.  
131.  
132. void loop(void)
133. {
134.   PORTD &= ~(1<<RS);
135.   lcd_bajt(0x80);
136.  
137.   PORTD |= (1<<RS);
138.  
139.  
140.  
141. }
142.  
143. void TWIInit(void)
144. {
145.   //set SCL to 400kHz
146.   TWSR = 0x00;
147.   TWBR = 0x0C;
148.   //enable TWI
149.   TWCR = (1<<TWEN);
150. }
151. void TWIStart(void)
152. {
153.   TWCR =
154.   (1<<TWINT)|(1<<TWSTA)|(1<<TWEN);
155.   while ((TWCR & (1<<TWINT)) == 0);
156. }
157. void TWIStop(void)
158. {
159.   TWCR =
160.   (1<<TWINT)|(1<<TWSTO)|(1<<TWEN);
161. }
162. void TWIWrite(uint8_t u8data)
163. {
164.   TWDR = u8data;
165.   TWCR = (1<<TWINT)|(1<<TWEN);
166.   while ((TWCR & (1<<TWINT)) == 0);
167. }
168. uint8_t TWIReadACK(void)
169. {
170.   TWCR =
171.   (1<<TWINT)|(1<<TWEN)|(1<<TWEA);
172.   while ((TWCR & (1<<TWINT)) == 0);
173.   return TWDR;
174. }
175. uint8_t TWIReadNACK(void)
176. {
177.   TWCR = (1<<TWINT)|(1<<TWEN);
178.   while ((TWCR & (1<<TWINT)) == 0);
179.   return TWDR;
180. }
181. uint8_t TWIGetStatus(void)
182. {
183.   uint8_t status;
184.   //mask status
185.   status = TWSR & 248;
186.   return status;
187. }
188.  
189. uint8_t EEWriteByte(uint16_t u16addr, uint8_t u8data)
190. {
191.   TWIStart();
192.   if (TWIGetStatus() != 8)
193.   return ERROR;
194.   //select device and send A2 A1 A0 address bits
195.   TWIWrite((EEDEVADR)|(uint8_t)((u16addr & 0x0700)>>7));
196.   if (TWIGetStatus() != 24)
197.   return ERROR;
198.   //send the rest of address
199.   TWIWrite((uint8_t)(u16addr));
200.   if (TWIGetStatus() != 40)
201.   return ERROR;
202.   //write byte to eeprom
203.   TWIWrite(u8data);
204.   if (TWIGetStatus() != 40)
205.   return ERROR;
206.   TWIStop();
207.   return SUCCESS;
208. }
209.  
210. uint8_t EEReadByte(uint16_t u16addr)
211. {
212.   //uint8_t databyte;
213.   uint8_t sdata;
214.   TWIStart();
215.   if (TWIGetStatus() != 8)
216.   return ERROR;
217.   //select device and send A2 A1 A0 address bits
218.   TWIWrite((EEDEVADR)|((uint8_t)((u16addr & 0x0700)>>7)));
219.   if (TWIGetStatus() != 36)
220.   return ERROR;
221.   //send the rest of address
222.   TWIWrite((uint8_t)(u16addr));
223.   if (TWIGetStatus() != 40)
224.   return ERROR;
225.   //send start
226.   TWIStart();
227.   if (TWIGetStatus() != 16)
228.   return ERROR;
229.   //select device and send read bit
230.   TWIWrite((EEDEVADR)|((uint8_t)((u16addr & 0x0700)>>7))|1);
231.   if (TWIGetStatus() != 64)
232.   return ERROR;
233.   sdata = TWIReadNACK();
234.   if (TWIGetStatus() != 88)
235.   return ERROR;
236.   TWIStop();
237.   return sdata;
238.   }
239.  
240. int main(void)
241. {
242.   TWIInit();
243.   uint8_t ddata = 0;
244.   uint8_t ew;
245.   setup();
246.   ew= EEWriteByte(5, 'b');
247.   if(ew==SUCCESS)
248.   {
249.     lcd_bajt('S');  
250.   }
251.   else lcd_bajt('E');
252.   _delay_ms(10);
253.   ddata = EEReadByte(5);
254.   if(ew==ERROR)
255.   {
256.   lcd_bajt('E');
257.   }
258.   else lcd_bajt('S');
259.  
260.   lcd_bajt(ddata);
261.   while(1)
262.   loop();
263.   return 0;
264.  
265. }