GPIO模拟IIC，可读可写，已验证 

  1 #include "iic.h"
  2 
  3 void IIC0_Delay(u32 count)
  4 {
  5     for(uint32_t i= count*3;i>0;i--){}
  6     //Sys_HardDelayUs(count);
  7     //rt_thread_mdelay(1);
  8 }
  9 void SCL0_OUT(void)
 10 {
 11     gpio_init(GPIOB, GPIO_MODE_OUT_OD, GPIO_OSPEED_50MHZ, GPIO_PIN_8);
 12 }
 13 void SDA0_OUT(void)
 14 {
 15     gpio_init(GPIOB, GPIO_MODE_OUT_OD, GPIO_OSPEED_50MHZ, GPIO_PIN_9);
 16 }
 17 void SDA0_IN(void)
 18 {
 19     gpio_init(GPIOB, GPIO_MODE_IN_FLOATING, GPIO_OSPEED_50MHZ, GPIO_PIN_9);
 20 }
 21 void IIC0_Start(void)
 22 {
 23     SDA0_OUT();
 24     SCL0(1);
 25     SDA0(1);
 26     IIC0_Delay(5);
 27     SDA0(0);
 28     IIC0_Delay(5);
 29     SCL0(0);
 30 }
 31 void IIC0_Stop(void)
 32 {
 33     SDA0_OUT();
 34     SCL0(0);
 35     SDA0(0);
 36     //IIC0_Delay(2);
 37     SCL0(1);
 38     IIC0_Delay(5);
 39     SDA0(1);
 40     IIC0_Delay(5);
 41     //SCL0(0);
 42 }
 43 
 44 
 45 u8 IIC0_Wait_Ack(void)
 46 {
 47     u16 cnt=0;
 48 
 49     SDA0(1);
 50     IIC0_Delay(5);
 51     SCL0(1);
 52     IIC0_Delay(5);
 53     SDA0_IN();
 54     while(READ_SDA0())
 55     {
 56         cnt++;
 57         IIC0_Delay(1);
 58         if(cnt>1000)
 59         {
 60         IIC0_Stop();
 61         return 1;
 62         }
 63     }
 64 
 65     SCL0(0);
 66     SDA0_OUT();
 67     SDA0(0);
 68     return 0;
 69 }
 70 
 71 
 72 void IIC0_write_Byte(u8 data)
 73 {
 74     u8 i;
 75     SCL0(0);
 76     IIC0_Delay(2);
 77     for(i = 0; i < 8; i++)
 78     {
 79         if((data & 0x80))
 80         {
 81             SDA0(1);
 82         }
 83         else
 84         {
 85             SDA0(0);
 86         }
 87 
 88         data <<= 1;
 89         //SCL0(0);
 90         IIC0_Delay(2);
 91         SCL0(1);
 92         IIC0_Delay(2);
 93         SCL0(0);
 94         IIC0_Delay(2);
 95     }
 96 }
 97 void IIC0_Write(u8* data,u32 len)
 98 {
 99     u8 ret=0;
100     IIC0_Start();
101     while(len)
102     {
103         len--;
104         IIC0_write_Byte(*data);
105         ret = IIC0_Wait_Ack();
106         if(ret)
107         {
108             //break;
109         }
110         data++;
111     }
112     IIC0_Stop();
113 }
114 void IIC0_Ack(void)
115 {
116     SCL0(0);
117     SDA0_OUT();
118     SDA0(0);
119     IIC0_Delay(2);
120     SCL0(1);
121     IIC0_Delay(2);
122     SCL0(0);
123 }
124 void IIC0_NAck(void)
125 {
126     SCL0(0);
127     SDA0_OUT();
128     SDA0(1);
129     IIC0_Delay(2);
130     SCL0(1);
131     IIC0_Delay(2);
132     SCL0(0);
133 
134 }
135 u8 IIC0_Read_Byte(u8 ack)
136 {
137     u8 i=0;
138     u8 bit=0;
139     u8 data=0;
140     SDA0_IN();
141     for(i=0;i<8;i++)
142     {
143         SCL0(0);
144         IIC0_Delay(2);
145         bit = READ_SDA0();
146         SCL0(1);
147         IIC0_Delay(2);
148         data |= (bit<<(7-i));
149     }
150     if(ack)
151     {
152         IIC0_Ack();
153     }
154     else
155     {
156         IIC0_NAck();
157     }
158     return data;
159 }
160 
161 void IIC0_Read(u8* data,u32 len,u8*out)
162 {
163     u8 i=0;
164     u8 ret=0;
165     IIC0_Start();
166     while(i<2)//slave address bit0=Write,register address write
167     {
168 
169         IIC0_write_Byte(*data);
170         ret = IIC0_Wait_Ack();
171         if(ret)
172         {
173         break;
174         }
175         i++;
176         data++;
177     }
178     IIC0_Start();
179     do//slave address bit0=Read
180     {
181         IIC0_write_Byte(*data);
182         ret = IIC0_Wait_Ack();
183         if(ret)
184         {
185         break;
186         }
187     }while(0);
188     while(len)
189     {
190         len--;
191         *out = IIC0_Read_Byte(len);// if(len==0),NACK;if (len!=0),ACK;
192         if(!len)break;
193         out++;
194     }
195     IIC0_Stop();
196     return;
197 }
198 
199 void i2c0_soft_init(void)
200 {
201     SCL0_OUT();
202     SDA0_OUT();
203 }
204 
205

 

posted @ 2022-06-17 12:13  =没有编程天赋=  阅读(172)  评论(0)    收藏  举报