LPC800+WIFI 数据上传，远程控制指示灯

zhangt0713 · 发表于 2021-6-28 00:07:33

本帖最后由 zhangt0713 于 2021-6-28 18:30 编辑

六月接近尾声，赶上社区的WiFi主题月，利用手上现有的资源，实现一个小功能。

实现内容：LPC800开发板，采集温湿度数据，通过WIFI上传到阿里云物联网平台，并在阿里云物联网平台实时显示，做个开关按钮，通过WIFI控制开发板上的蓝色指示灯亮灭.

一、硬件组成+开发工具

硬件：LPC800DIP、ESP32模块、GXHT30温湿度传感器组成

开发工具：Keil、阿里云物联网平台

二、组成框图

三、开发准备

1.阿里云物联网平台主要采用MQTT协议进行数据传输，注册一个阿里云物联网平台账号，建立项目，产品设备

2.阿里云三元组，和密钥计算，

3.采用MQTT.fx，模拟连接物联网平台，实现数据的发送

4.利用串口调试助手连接ESP32，发送AT指令连接阿里云物联网平台上的设备。

以上步骤完成后可以在，LPC800上实现具体的功能：

LPC800主要温湿度的采集，并通过AT命令控制ESP32的WIFI连接。用到的资源有，串口，定时器，I2C。

四、主要初始化和命令

1.温湿度传感器的数据通过LPC800的I2C实现温湿度的读取

按照上述步骤初始化I2C，

/* function to write a byte to GXHT30*/
void Write_GXHT30_CMD(uint8_t CMD_MSB, uint8_t CMD_LSB)
{
WaitI2CMasterState(LPC_I2C0, I2C_STAT_MSTST_IDLE); // Wait the master state to be idle
LPC_I2C0->MSTDAT = (I2C_ADDR_GXHT30<<1) | 0; // Address with 0 for RWn bit (WRITE)
LPC_I2C0->MSTCTL = CTL_MSTSTART; // Start the transaction by setting the MSTSTART bit to 1 in the Master control register.
WaitI2CMasterState(LPC_I2C0, I2C_STAT_MSTST_TX); // Wait for the address to be ACK'd
LPC_I2C0->MSTDAT = CMD_MSB; // Send the data to the slave
LPC_I2C0->MSTCTL = CTL_MSTCONTINUE; // Continue the transaction
WaitI2CMasterState(LPC_I2C0, I2C_STAT_MSTST_TX); // Wait for the data to be ACK'd
LPC_I2C0->MSTDAT = CMD_LSB; // Send the data to the slave
LPC_I2C0->MSTCTL = CTL_MSTCONTINUE; // Continue the transaction
WaitI2CMasterState(LPC_I2C0, I2C_STAT_MSTST_TX); // Wait for the data to be ACK'd
LPC_I2C0->MSTCTL = CTL_MSTSTOP; // Send a stop to end the transaction
}
void Read_GXHT30_CMD(uint8_t *data,uint8_t Num)
{
uint8_t i;
WaitI2CMasterState(LPC_I2C0, I2C_STAT_MSTST_IDLE); // Wait the master state to be idle
LPC_I2C0->MSTDAT = (I2C_ADDR_GXHT30<<1) | 1; // Address with 1 for RWn bit (READ)
LPC_I2C0->MSTCTL = CTL_MSTSTART; // Start the transaction by setting the MSTSTART bit to 1 in the Master control register.
for (i=0;i<Num;i++)
{
while(!(LPC_I2C0->STAT & STAT_MSTPEND));
data[i] = LPC_I2C0->MSTDAT;
LPC_I2C0->MSTCTL = CTL_MSTCONTINUE;
}
LPC_I2C0->MSTCTL = CTL_MSTSTOP; // Send a stop to end the transaction
}
void GXHT30_DATA(void)
{
uint8_t buff[6];
uint16_t tem,hum;
Write_GXHT30_CMD(0x24, 0x16);
Delay_ms(20);
Read_GXHT30_CMD(buff,6);
tem = ((buff[0]<<8) | buff[1]);//
hum = ((buff[3]<<8) | buff[4]);//
Temperature =(175.0 * (float)tem/65535.0 -45.0); //
Humidity= (100.0*hum/65535.0);
}