Project has been debugged and needs of small partners left a message at the mailbox
I have uploaded in CSDN, https: //download.csdn.net/download/qq_41840148/12185225
I simulated hardware is PB6 and PB7, PB7 do SDA, PB6 do SCL
There are two holes it certainly is 3.3V and GND wiring method this way, not on the map
Everyone to look at the way the module
There are printed on the serial Assistant pictures
In addition to temperature and humidity data, those above printed above " start1234 ------ success" is the process of debugging the code I
Because there is no lazy delete it, you can decide if they use their own fate
Temperature and humidity display I do not have to print out the unit, you can add yourself
After reading the effect of the process is now speaking about the development of
1, the first is to prepare an IO port simulation I2C project, this online resource is too much will not repeat
2, find the specifications AHT10 in http://www.aosong.com/ Aosong electronic official website, here it is my Specification 19 October 15
3, then you can start looking at the specifications for programming
Then turn AHT10 data sheet, which is on page 5 of 7 specifications sensor communication
The sample program is written in C, I think the format should guess arduino, no attention, we continue to
So what of 5.1 sensor to tell you that we have the power to skip it
No one should forget sensor to supply it ...
5.2 I2C tell us every time transmission of data must have a start and stop Well
So let's write code for these two functions
1 void I2C_Start(void) 2 { 3 SDA_OUT(); 4 IIC_SCL = 1; 5 delay_ms(4); 6 7 IIC_SDA = 1; 8 delay_ms(4); 9 IIC_SDA = 0; 10 delay_ms(4); 11 12 IIC_SCL = 0; 13 delay_ms(4); 14 }
1 void I2C_Stop(void) 2 { 3 SDA_OUT(); 4 IIC_SDA = 0; 5 delay_ms(4); 6 7 IIC_SCL = 1; 8 delay_ms(4); 9 10 IIC_SDA = 1; 11 delay_ms(4); 12 }
上面从数据手册截的图下面的字已经解释了开始信号和停止信号的过程了嘛
这里也重复一遍吧
I2C的启动：SCL为高电平时，SDA的电平从高变到低，这就是启动信号
I2C的停止：SCL为高电平时，SDA的电平从低变到高，这就是停止信号
另外提一个I2C协议的东西，假如我已经启动传输数据了，当SCL为高电平的时候，SDA是不允许变动电平的，必须保持稳定
传输数据中，SCL为高时，数据传输SDA数据必须保持其中一种状态
当传输完成时，SCL拉低时，SDA才可以变动电平等待下一次发送
我们继续
5.3主机stm32往从机AHT10发送命令
从实物图的那个103电阻我们也可以看出AHT10的设备地址是0x38
那么添加一个SDA的方向我们要传输的数据是什么呢
假设我们SDA的方向是主机往从机写内容W：‘0’
我用画图描述一下
就是往0x38后面添加一个0，最前面的数据丢掉，转为新的16进制数据0x70
1110 0001代表初始化也就是0xE1
1010 1100代表温湿度测量也就是0xBA
我们继续下一页来到传感器的读取流程
这个流程的函数我们写一下，代码中if else打印的内容是调试过程可以删除
第一个使能位Bit[3]不为1时的函数，初始化代码
1 void init_AHT10(void) 2 { 3 I2C_Start(); 4 5 I2C_WriteByte(0x70); 6 ack_status = Receive_ACK(); 7 if(ack_status) printf("3"); 8 else printf("3-n-"); 9 I2C_WriteByte(0xE1); 10 ack_status = Receive_ACK(); 11 if(ack_status) printf("4"); 12 else printf("4-n-"); 13 I2C_WriteByte(0x08); 14 ack_status = Receive_ACK(); 15 if(ack_status) printf("5"); 16 else printf("5-n-"); 17 I2C_WriteByte(0x00); 18 ack_status = Receive_ACK(); 19 if(ack_status) printf("6"); 20 else printf("6-n-"); 21 I2C_Stop(); 22 }
第二个触发测量的函数
1 void startMeasure_AHT10(void) 2 { 3 //------------ 4 I2C_Start(); 5 6 I2C_WriteByte(0x70); 7 ack_status = Receive_ACK(); 8 if(ack_status) printf("7"); 9 else printf("7-n-"); 10 I2C_WriteByte(0xAC); 11 ack_status = Receive_ACK(); 12 if(ack_status) printf("8"); 13 else printf("8-n-"); 14 I2C_WriteByte(0x33); 15 ack_status = Receive_ACK(); 16 if(ack_status) printf("9"); 17 else printf("9-n-"); 18 I2C_WriteByte(0x00); 19 ack_status = Receive_ACK(); 20 if(ack_status) printf("10"); 21 else printf("10-n-"); 22 I2C_Stop(); 23 }
第三个发送0x71读取采集的温湿度数据
1 void read_AHT10(void) 2 { 3 uint8_t i; 4 5 for(i=0; i<6; i++) 6 { 7 readByte[i]=0; 8 } 9 10 //------------- 11 I2C_Start(); 12 13 I2C_WriteByte(0x71); 14 ack_status = Receive_ACK(); 15 if(ack_status) printf("11"); 16 else printf("11-n-"); 17 readByte[0]= I2C_ReadByte(); 18 printf("test0:%d",readByte[0]); 19 Send_ACK(); 20 21 readByte[1]= I2C_ReadByte(); 22 printf("test1:%d",readByte[1]); 23 Send_ACK(); 24 25 readByte[2]= I2C_ReadByte(); 26 printf("test2:%d",readByte[2]); 27 Send_ACK(); 28 29 readByte[3]= I2C_ReadByte(); 30 printf("test3:%d",readByte[3]); 31 Send_ACK(); 32 33 readByte[4]= I2C_ReadByte(); 34 printf("test4:%d",readByte[4]); 35 Send_ACK(); 36 37 readByte[5]= I2C_ReadByte(); 38 printf("test5:%d",readByte[5]); 39 SendNot_Ack(); 40 //Send_ACK(); 41 42 I2C_Stop(); 43 44 //-------------- 45 if( (readByte[0] & 0x68) == 0x08 ) 46 { 47 H1 = readByte[1]; 48 H1 = (H1<<8) | readByte[2]; 49 H1 = (H1<<8) | readByte[3]; 50 H1 = H1>>4; 51 52 H1 = (H1*1000)/1024/1024; 53 54 T1 = readByte[3]; 55 T1 = T1 & 0x0000000F; 56 T1 = (T1<<8) | readByte[4]; 57 T1 = (T1<<8) | readByte[5]; 58 59 T1 = (T1*2000)/1024/1024 - 500; 60 61 AHT10_OutData[0] = (H1>>8) & 0x000000FF; 62 AHT10_OutData[1] = H1 & 0x000000FF; 63 64 AHT10_OutData[2] = (T1>>8) & 0x000000FF; 65 AHT10_OutData[3] = T1 & 0x000000FF; 66 printf("成功了"); 67 } 68 else 69 { 70 AHT10_OutData[0] = 0xFF; 71 AHT10_OutData[1] = 0xFF; 72 73 AHT10_OutData[2] = 0xFF; 74 AHT10_OutData[3] = 0xFF; 75 printf("失败了"); 76 77 } 78 printf("\r\n"); 79 printf("温度:%d%d.%d",T1/100,(T1/10)%10,T1%10); 80 printf("湿度:%d%d.%d",H1/100,(H1/10)%10,H1%10); 81 printf("\r\n"); 82 }
第四个计算温湿度值的内容和第三个组合在一起了
手册中有个基本命令集，前2个我们已经在上面的代码实现了，把软复位也完成一下
1 void reset_AHT10(void) 2 { 3 4 I2C_Start(); 5 6 I2C_WriteByte(0x70); 7 ack_status = Receive_ACK(); 8 if(ack_status) printf("1"); 9 else printf("1-n-"); 10 I2C_WriteByte(0xBA); 11 ack_status = Receive_ACK(); 12 if(ack_status) printf("2"); 13 else printf("2-n-"); 14 I2C_Stop(); 15 16 /* 17 AHT10_OutData[0] = 0; 18 AHT10_OutData[1] = 0; 19 AHT10_OutData[2] = 0; 20 AHT10_OutData[3] = 0; 21 */ 22 }
那么到这里我们要用的代码已经基本完成了
如果仔细看我们代码完全是按照手册里面的图来编程的
到了最后一步，把上面四个函数写成一个流程函数就可以使用AHT10显示温湿度
流程里面我们默认校准使能为0，开头进行一次软复位在执行采集流程
1 void read_AHT10_once(void) 2 { 3 delay_ms(10); 4 5 reset_AHT10(); 6 delay_ms(10); 7 8 init_AHT10(); 9 delay_ms(10); 10 11 startMeasure_AHT10(); 12 delay_ms(80); 13 14 read_AHT10(); 15 delay_ms(5); 16 }
这里还有一张表10没有介绍
他在采集数据的最后一步if( (readByte[0] & 0x68) == 0x08 )用得上
因为时间问题不多介绍了，画图一下就能明白为什么要这个判断
记录到这里就结束了，感觉记得东西有点乱
今天也加油啊
