PSoc™62开发板之IoT应用

实验目的

使用PSoc62™开发板驱动OLED模块,实时监控室内的光照强度、温度信息

实验准备

  • PSoc62™开发板
  • SSD1309 OLED模块
  • DS18B20温度传感器
  • BH1750光照传感器

模块电路

SSD1309

OLED模块的电路连接和模块配置教程请参考之前的文章,这里不详细展开描述

BH1750

模块SCL、SDA、GND引脚分别接CON5的P8.0、P8.1、GND引脚,VCC则接CON6的3.3V引脚

实物连接图

i2c引脚配置,需要在RT-Thread Studio里边配置使用模拟i2c引脚P8.0和P8.1(分别对应编号64、65)

有需要的可以使能i2c-tools这个包

模块的设备地址用i2c-tools查看是0x23

DS18B20

模块out引脚连接CON8处的P10.5引脚,VCC、GND可以连接CON6处的3.3V、GND,模块已经接了上拉电阻,这里不需要额外配置

实物连接图

程序设计

SSD1309

OLED模块的程序设计请参考之前的文章

DS18B20

传感器驱动代码

#define DS18B20_PIN         GET_PIN(10, 5)
#define DS18B20_DQ_OUT(x)   rt_pin_write(DS18B20_PIN, x)
#define DS18B20_DQ_IN       rt_pin_read(DS18B20_PIN)

// 复位DS18B20
static void ds18b20_reset(void)
{
    DS18B20_DQ_OUT(0);  
    rt_hw_us_delay(750);      
    DS18B20_DQ_OUT(1); 
    rt_hw_us_delay(15);      
}

// 等待DS18B20的回应
uint8_t ds18b20_check(void)
{
    uint8_t retry = 0;
    uint8_t rval = 0;

    while (DS18B20_DQ_IN && retry < 200)  
    {
        retry++;
        rt_hw_us_delay(1);
    }

    if (retry >= 200)
    {
        rval = 1;
    }
    else
    {
        retry = 0;

        while (!DS18B20_DQ_IN && retry < 240) 
        {
            retry++;
            rt_hw_us_delay(1);
        }

        if (retry >= 240) rval = 1;
    }

    return rval;
}

// 从DS18B20读取一个位
static uint8_t ds18b20_read_bit(void)
{
    uint8_t data = 0;
    DS18B20_DQ_OUT(0);
    rt_hw_us_delay(2);
    DS18B20_DQ_OUT(1);
    rt_hw_us_delay(12);

    if (DS18B20_DQ_IN)
    {
        data = 1;
    }

    rt_hw_us_delay(50);
    return data;
}

// 从DS18B20读取一个字节
static uint8_t ds18b20_read_byte(void)
{
    uint8_t i, b, data = 0;

    for (i = 0; i < 8; i++)
    {
        b = ds18b20_read_bit(); 

        data |= b << i;       
    }

    return data;
}

// 写一个字节到DS18B20
static void ds18b20_write_byte(uint8_t data)
{
    uint8_t j;

    for (j = 1; j <= 8; j++)
    {
        if (data & 0x01)
        {
            DS18B20_DQ_OUT(0); 
            rt_hw_us_delay(2);
            DS18B20_DQ_OUT(1);
            rt_hw_us_delay(60);
        }
        else
        {
            DS18B20_DQ_OUT(0); 
            rt_hw_us_delay(60);
            DS18B20_DQ_OUT(1);
            rt_hw_us_delay(2);
        }

        data >>= 1;             
    }
}

// 开始温度转换
static void ds18b20_start(void)
{
    ds18b20_reset();
    ds18b20_check();
    ds18b20_write_byte(0xcc);   /*  skip rom */
    ds18b20_write_byte(0x44);   /*  convert */
}

// 初始化DS18B20的IO口 DQ 同时检测DS18B20的存在
uint8_t ds18b20_init(void)
{
    rt_pin_mode(DS18B20_PIN, PIN_MODE_OUTPUT_OD);
//    rt_pin_write(DS18B20_PIN, PIN_HIGH);

    ds18b20_reset();
    return ds18b20_check();
}

// 从ds18b20得到温度值(精度:0.1C)
short ds18b20_get_temperature(void)
{
    uint8_t flag = 1;           /* 默认温度为正数 */
    uint8_t TL, TH;
    short temp;

    ds18b20_start();            /*  ds1820 start convert */
    ds18b20_reset();
    ds18b20_check();
    ds18b20_write_byte(0xcc);   /*  skip rom */
    ds18b20_write_byte(0xbe);   /*  convert */
    TL = ds18b20_read_byte();   /*  LSB */
    TH = ds18b20_read_byte();   /*  MSB */

    if (TH > 7)
    {
        TH = ~TH;
        TL = ~TL;
        flag = 0;   /* 温度为负 */
    }

    temp = TH;      /* 获得高八位 */
    temp <<= 8;
    temp += TL;     /* 获得底八位 */
    temp = (double)temp * 0.625;    /* 转换 */

    if (flag == 0)
    {
        temp = -temp;   /* 将温度转换成负温度 */
    }

    return temp;
}

读取温度值

// ds18b20
ds18b20_init();

// ssd1309
OLED_Init();
OLED_Clear();

for (;;)
{
    // ds18b20
    int val = ds18b20_get_temperature();
    rt_memset(buff, 20, 0);
    rt_sprintf(buff, "temp : %d.%d'C  ", val / 10, val % 10);
    OLED_ShowString(10, 2, buff);
    rt_thread_mdelay(200);
}

用逻辑分析仪抓一下单总线的读写时序,读取的数据(0x0185,大概是室温20来度)是OK的

 

BH1750

模块驱动代码,用的是i2c1总线

#define BH1750_I2C_BUS_NAME     "i2c1"
#define BH1750_ADDR             0x23

static rt_uint8_t buffer[2];
static uint16_t light = 0;
static struct rt_i2c_bus_device *i2c_bus;

static int read_i2c_reg(rt_uint8_t reg_addr, rt_uint8_t *data, rt_uint8_t len)
{
    struct rt_i2c_msg msgs[2];
    msgs[0].addr = BH1750_ADDR;
    msgs[0].flags = RT_I2C_WR;
    msgs[0].buf = &reg_addr;
    msgs[0].len = 1;

    msgs[1].addr = BH1750_ADDR;
    msgs[1].flags = RT_I2C_RD;
    msgs[1].buf = data;
    msgs[1].len = len;

    if (rt_i2c_transfer(i2c_bus, msgs, 2) == 2)
    {
        return RT_EOK;
    }
    else
        return -RT_ERROR;
}

static int8_t write_i2c_reg(uint8_t data)
{
    struct rt_i2c_msg msgs[2];

    msgs[0].addr  = BH1750_ADDR;
    msgs[0].flags = RT_I2C_WR;
    msgs[0].buf   = NULL;
    msgs[0].len   = 0;

    msgs[1].addr  = BH1750_ADDR;
    msgs[1].flags = RT_I2C_WR | RT_I2C_NO_START;
    msgs[1].buf   = &data;
    msgs[1].len   = 1;

    if (rt_i2c_transfer(i2c_bus, msgs, 2) != 2)
    {
        return -RT_ERROR;
    }

    return RT_EOK;
}

void BH1750_Init()
{
    write_i2c_reg(0x10);
}

读取光照强度值

// bh1750
i2c_bus = (struct rt_i2c_bus_device *)rt_device_find(BH1750_I2C_BUS_NAME);
if (i2c_bus == RT_NULL)
{
    rt_kprintf("can't find %s device!\n", BH1750_I2C_BUS_NAME);
    return RT_ERROR;
}

BH1750_Init();
rt_thread_mdelay(500);

// ssd1309
OLED_Init();
OLED_Clear();

for (;;)
{
    // bh1750
    BH1750_Init();
    rt_thread_mdelay(200);
    read_i2c_reg(0, buffer, 2);
    light = ((buffer[0] << 8) | buffer[1]) / 1.2;
    rt_memset(buff, 20, 0);
    rt_sprintf(buff, "light : %d lx      ", light);
    OLED_ShowString(10, 5, buff);
    rt_thread_mdelay(150);
}

 

整合代码

以下代码用于读取DS18B20的温度值、BH1750的光照强度

#include <rtthread.h>
#include <rtdevice.h>
#include "drv_gpio.h"

#define DS18B20_PIN         GET_PIN(10, 5)
#define DS18B20_DQ_OUT(x)   rt_pin_write(DS18B20_PIN, x)
#define DS18B20_DQ_IN       rt_pin_read(DS18B20_PIN)

// 复位DS18B20
static void ds18b20_reset(void)
{
    DS18B20_DQ_OUT(0);  /* 拉低DQ,复位 */
    rt_hw_us_delay(750);      /* 拉低750us */
    DS18B20_DQ_OUT(1);  /* DQ=1, 释放复位 */
    rt_hw_us_delay(15);       /* 延迟15US */
}

// 等待DS18B20的回应
uint8_t ds18b20_check(void)
{
    uint8_t retry = 0;
    uint8_t rval = 0;

    while (DS18B20_DQ_IN && retry < 200)    /* 等待DQ变低, 等待200us */
    {
        retry++;
        rt_hw_us_delay(1);
    }

    if (retry >= 200)
    {
        rval = 1;
    }
    else
    {
        retry = 0;

        while (!DS18B20_DQ_IN && retry < 240)   /* 等待DQ变高, 等待240us */
        {
            retry++;
            rt_hw_us_delay(1);
        }

        if (retry >= 240) rval = 1;
    }

    return rval;
}

// 从DS18B20读取一个位
static uint8_t ds18b20_read_bit(void)
{
    uint8_t data = 0;
    DS18B20_DQ_OUT(0);
    rt_hw_us_delay(2);
    DS18B20_DQ_OUT(1);
    rt_hw_us_delay(12);

    if (DS18B20_DQ_IN)
    {
        data = 1;
    }

    rt_hw_us_delay(50);
    return data;
}

// 从DS18B20读取一个字节
static uint8_t ds18b20_read_byte(void)
{
    uint8_t i, b, data = 0;

    for (i = 0; i < 8; i++)
    {
        b = ds18b20_read_bit(); /* DS18B20先输出低位数据 ,高位数据后输出 */

        data |= b << i;         /* 填充data的每一位 */
    }

    return data;
}

// 写一个字节到DS18B20
static void ds18b20_write_byte(uint8_t data)
{
    uint8_t j;

    for (j = 1; j <= 8; j++)
    {
        if (data & 0x01)
        {
            DS18B20_DQ_OUT(0);  /*  Write 1 */
            rt_hw_us_delay(2);
            DS18B20_DQ_OUT(1);
            rt_hw_us_delay(60);
        }
        else
        {
            DS18B20_DQ_OUT(0);  /*  Write 0 */
            rt_hw_us_delay(60);
            DS18B20_DQ_OUT(1);
            rt_hw_us_delay(2);
        }

        data >>= 1;             /* 右移,获取高一位数据 */
    }
}

// 开始温度转换
static void ds18b20_start(void)
{
    ds18b20_reset();
    ds18b20_check();
    ds18b20_write_byte(0xcc);   /*  skip rom */
    ds18b20_write_byte(0x44);   /*  convert */
}

// 初始化DS18B20的IO口 DQ 同时检测DS18B20的存在
uint8_t ds18b20_init(void)
{
    rt_pin_mode(DS18B20_PIN, PIN_MODE_OUTPUT_OD);
//    rt_pin_write(DS18B20_PIN, PIN_HIGH);

    ds18b20_reset();
    return ds18b20_check();
}

// 从ds18b20得到温度值(精度:0.1C)
short ds18b20_get_temperature(void)
{
    uint8_t flag = 1;           /* 默认温度为正数 */
    uint8_t TL, TH;
    short temp;

    ds18b20_start();            /*  ds1820 start convert */
    ds18b20_reset();
    ds18b20_check();
    ds18b20_write_byte(0xcc);   /*  skip rom */
    ds18b20_write_byte(0xbe);   /*  convert */
    TL = ds18b20_read_byte();   /*  LSB */
    TH = ds18b20_read_byte();   /*  MSB */

    if (TH > 7)
    {
        TH = ~TH;
        TL = ~TL;
        flag = 0;   /* 温度为负 */
    }

    temp = TH;      /* 获得高八位 */
    temp <<= 8;
    temp += TL;     /* 获得底八位 */
    temp = (double)temp * 0.625;    /* 转换 */

    if (flag == 0)
    {
        temp = -temp;   /* 将温度转换成负温度 */
    }

    return temp;
}

///////////////////////////////////////////////////

#include "stdlib.h"
#include "oledfont.h"

// 绑定PSoc62板子的GPIO
#define CS_PIN      GET_PIN(10, 0)
#define DC_PIN      GET_PIN(10, 1)
#define RES_PIN     GET_PIN(10, 2)
#define SDA_PIN     GET_PIN(10, 3)
#define SCL_PIN     GET_PIN(10, 4)
#define WR_PIN      GET_PIN(0, 1)
#define RD_PIN      GET_PIN(0, 1)

// OLED模式设置
#define OLED_MODE   0
#define SIZE        16
#define XLevelL     0x00
#define XLevelH     0x10
#define Max_Column  128
#define Max_Row     64
#define Brightness  0xFF
#define X_WIDTH     128
#define Y_WIDTH     64

// OLED端口定义
#define OLED_CS_Clr()   rt_pin_write(CS_PIN, PIN_LOW)
#define OLED_CS_Set()   rt_pin_write(CS_PIN, PIN_HIGH)
#define OLED_RST_Clr()  rt_pin_write(RES_PIN, PIN_LOW)
#define OLED_RST_Set()  rt_pin_write(RES_PIN, PIN_HIGH)
#define OLED_DC_Clr()   rt_pin_write(DC_PIN, PIN_LOW)
#define OLED_DC_Set()   rt_pin_write(DC_PIN, PIN_HIGH)
#define OLED_SDIN_Clr() rt_pin_write(SDA_PIN, PIN_LOW)
#define OLED_SDIN_Set() rt_pin_write(SDA_PIN, PIN_HIGH)
#define OLED_SCLK_Clr() rt_pin_write(SCL_PIN, PIN_LOW)
#define OLED_SCLK_Set() rt_pin_write(SCL_PIN, PIN_HIGH)
#define OLED_WR_Clr()   rt_pin_write(WR_PIN, PIN_LOW)
#define OLED_WR_Set()   rt_pin_write(WR_PIN, PIN_HIGH)
#define OLED_RD_Clr()   rt_pin_write(RD_PIN, PIN_LOW)
#define OLED_RD_Set()   rt_pin_write(RD_PIN, PIN_HIGH)

#define OLED_CMD  0 // 写命令
#define OLED_DATA 1 // 写数据

#define u8 unsigned char
#define u32 unsigned int

static u8 buff[20];

// 向SSD1309写入一个字节数据:dat -> 要写入的数据 or命令,cmd -> 数据or命令
void OLED_WR_Byte(u8 dat, u8 cmd)
{
    u8 i;
    if(cmd)
        OLED_DC_Set();
    else
        OLED_DC_Clr();
    OLED_CS_Clr();
    for(i=0; i < 8; i++)
    {
        OLED_SCLK_Clr();
        if(dat & 0x80)
            OLED_SDIN_Set();
        else
            OLED_SDIN_Clr();
        OLED_SCLK_Set();
        dat <<= 1;
    }
    OLED_CS_Set();
    OLED_DC_Set();
}

// 设置绘制的坐标
void OLED_Set_Pos(unsigned char x, unsigned char y)
{
    OLED_WR_Byte(0xb0 + y, OLED_CMD);
    OLED_WR_Byte(((x & 0xf0) >> 4) | 0x10, OLED_CMD);
    OLED_WR_Byte((x & 0x0f) | 0x01, OLED_CMD);
}

// 开启OLED显示
void OLED_Display_On(void)
{
    OLED_WR_Byte(0X8D, OLED_CMD);
    OLED_WR_Byte(0X14, OLED_CMD);
    OLED_WR_Byte(0XAF, OLED_CMD);
}

// 关闭OLED显示
void OLED_Display_Off(void)
{
    OLED_WR_Byte(0X8D, OLED_CMD);
    OLED_WR_Byte(0X10, OLED_CMD);
    OLED_WR_Byte(0XAE, OLED_CMD);
}

// 清屏函数,屏幕会置为黑色
void OLED_Clear(void)
{
    u8 i,n;
    for(i=0;i<8;i++)
    {
        OLED_WR_Byte (0xb0 + i, OLED_CMD);      // 设置页地址(0~7)
        OLED_WR_Byte (0x00, OLED_CMD);          // 设置显示位置—列低地址
        OLED_WR_Byte (0x10, OLED_CMD);          // 设置显示位置—列高地址
        for(n = 0; n < 128; n++)
            OLED_WR_Byte(0, OLED_DATA);
    }
}

// 绘制字符
void OLED_ShowChar(u8 x,u8 y,u8 chr)
{
    unsigned char c=0,i=0;
    c=chr-' ';//得到偏移后的值
    if(x>Max_Column-1)
    {
        x=0;
        y=y+2;
    }
    if(SIZE ==16)
    {
        OLED_Set_Pos(x,y);
        for(i=0;i<8;i++)
            OLED_WR_Byte(F8X16[c*16+i],OLED_DATA);
        OLED_Set_Pos(x,y+1);
        for(i=0;i<8;i++)
            OLED_WR_Byte(F8X16[c*16+i+8],OLED_DATA);
    }
    else {
        OLED_Set_Pos(x,y+1);
        for(i=0;i<6;i++)
            OLED_WR_Byte(F6x8[c][i],OLED_DATA);

    }
}

// 显示一个字符号串
void OLED_ShowString(u8 x,u8 y,u8 *chr)
{
    unsigned char j=0;
    while (chr[j]!='\0')
    {
        OLED_ShowChar(x,y,chr[j]);
        x+=8;
        if(x>120)
        {
            x=0;y+=2;
        }
        j++;
    }
}

// 显示数字
void OLED_ShowNum(u8 x,u8 y,u32 num)
{
    rt_memset(buff, 20, 0);
    rt_sprintf(buff, "%d", num);
    OLED_ShowString(x, y, buff);
}

// 显示汉字
void OLED_ShowCHinese(u8 x,u8 y,u8 no)
{
    u8 t,adder=0;
    OLED_Set_Pos(x,y);
    for(t=0;t<16;t++)
    {
        OLED_WR_Byte(Hzk[2*no][t],OLED_DATA);
        adder+=1;
    }
    OLED_Set_Pos(x,y+1);
    for(t=0;t<16;t++)
    {
        OLED_WR_Byte(Hzk[2*no+1][t],OLED_DATA);
        adder+=1;
    }
}


// 初始化SSD1309
void OLED_Init(void)
{
    // init gpios
    rt_pin_mode(CS_PIN, PIN_MODE_OUTPUT);
    rt_pin_mode(DC_PIN, PIN_MODE_OUTPUT);
    rt_pin_mode(RES_PIN, PIN_MODE_OUTPUT);
    rt_pin_mode(SDA_PIN, PIN_MODE_OUTPUT);
    rt_pin_mode(SCL_PIN, PIN_MODE_OUTPUT);

    OLED_RST_Set();
    rt_thread_mdelay(100);
    OLED_RST_Clr();
    rt_thread_mdelay(100);
    OLED_RST_Set();

    OLED_WR_Byte(0xAE,OLED_CMD);    //--turn off oled panel
    OLED_WR_Byte(0x00,OLED_CMD);    //---set low column address
    OLED_WR_Byte(0x10,OLED_CMD);    //---set high column address
    OLED_WR_Byte(0x40,OLED_CMD);    //--set start line address  Set Mapping RAM Display Start Line (0x00~0x3F)
    OLED_WR_Byte(0x81,OLED_CMD);    //--set contrast control register
    OLED_WR_Byte(0xCF,OLED_CMD);    // Set SEG Output Current Brightness
    OLED_WR_Byte(0xA1,OLED_CMD);    //--Set SEG/Column Mapping     0xa0左右反置 0xa1正常
    OLED_WR_Byte(0xC8,OLED_CMD);    //Set COM/Row Scan Direction   0xc0上下反置 0xc8正常
    OLED_WR_Byte(0xA6,OLED_CMD);    //--set normal display
    OLED_WR_Byte(0xA8,OLED_CMD);    //--set multiplex ratio(1 to 64)
    OLED_WR_Byte(0x3f,OLED_CMD);    //--1/64 duty
    OLED_WR_Byte(0xD3,OLED_CMD);    //-set display offset   Shift Mapping RAM Counter (0x00~0x3F)
    OLED_WR_Byte(0x00,OLED_CMD);    //-not offset
    OLED_WR_Byte(0xd5,OLED_CMD);    //--set display clock divide ratio/oscillator frequency
    OLED_WR_Byte(0x80,OLED_CMD);    //--set divide ratio, Set Clock as 100 Frames/Sec
    OLED_WR_Byte(0xD9,OLED_CMD);    //--set pre-charge period
    OLED_WR_Byte(0xF1,OLED_CMD);    //Set Pre-Charge as 15 Clocks & Discharge as 1 Clock
    OLED_WR_Byte(0xDA,OLED_CMD);    //--set com pins hardware configuration
    OLED_WR_Byte(0x12,OLED_CMD);
    OLED_WR_Byte(0xDB,OLED_CMD);    //--set vcomh
    OLED_WR_Byte(0x40,OLED_CMD);    //Set VCOM Deselect Level
    OLED_WR_Byte(0x20,OLED_CMD);    //-Set Page Addressing Mode (0x00/0x01/0x02)
    OLED_WR_Byte(0x02,OLED_CMD);    //
    OLED_WR_Byte(0x8D,OLED_CMD);    //--set Charge Pump enable/disable
    OLED_WR_Byte(0x14,OLED_CMD);    //--set(0x10) disable
    OLED_WR_Byte(0xA4,OLED_CMD);    // Disable Entire Display On (0xa4/0xa5)
    OLED_WR_Byte(0xA6,OLED_CMD);    // Disable Inverse Display On (0xa6/a7)
    OLED_WR_Byte(0xAF,OLED_CMD);    //--turn on oled panel

    OLED_WR_Byte(0xAF,OLED_CMD);    /*display ON*/
    OLED_Clear();
    OLED_Set_Pos(0,0);
}

//////////////////////////
#define BH1750_I2C_BUS_NAME     "i2c1"
#define BH1750_ADDR             0x23

static rt_uint8_t buffer[2];
static uint16_t light = 0;
static struct rt_i2c_bus_device *i2c_bus;

static int read_i2c_reg(rt_uint8_t reg_addr, rt_uint8_t *data, rt_uint8_t len)
{
    struct rt_i2c_msg msgs[2];
    msgs[0].addr = BH1750_ADDR;
    msgs[0].flags = RT_I2C_WR;
    msgs[0].buf = ®_addr;
    msgs[0].len = 1;

    msgs[1].addr = BH1750_ADDR;
    msgs[1].flags = RT_I2C_RD;
    msgs[1].buf = data;
    msgs[1].len = len;

    if (rt_i2c_transfer(i2c_bus, msgs, 2) == 2)
    {
        return RT_EOK;
    }
    else
        return -RT_ERROR;
}

static int8_t write_i2c_reg(uint8_t data)
{
    struct rt_i2c_msg msgs[2];

    msgs[0].addr  = BH1750_ADDR;
    msgs[0].flags = RT_I2C_WR;
    msgs[0].buf   = NULL;
    msgs[0].len   = 0;

    msgs[1].addr  = BH1750_ADDR;
    msgs[1].flags = RT_I2C_WR | RT_I2C_NO_START;
    msgs[1].buf   = &data;
    msgs[1].len   = 1;

    if (rt_i2c_transfer(i2c_bus, msgs, 2) != 2)
    {
        return -RT_ERROR;
    }

    return RT_EOK;
}

void BH1750_Init()
{
    write_i2c_reg(0x10);
}

int main(void)
{
    // ds18b20
    ds18b20_init();

    // bh1750
    i2c_bus = (struct rt_i2c_bus_device *)rt_device_find(BH1750_I2C_BUS_NAME);
    if (i2c_bus == RT_NULL)
    {
        rt_kprintf("can't find %s device!\n", BH1750_I2C_BUS_NAME);
        return RT_ERROR;
    }

    BH1750_Init();
    rt_thread_mdelay(500);

    // ssd1309
    OLED_Init();
    OLED_Clear();

    for (;;)
    {
        // ds18b20
        int val = ds18b20_get_temperature();
        rt_memset(buff, 20, 0);
        rt_sprintf(buff, "temp : %d.%d'C  ", val / 10, val % 10);
        OLED_ShowString(10, 2, buff);
        rt_thread_mdelay(200);

        // bh1750
        BH1750_Init();
        rt_thread_mdelay(200);
        read_i2c_reg(0, buffer, 2);
        light = ((buffer[0] << 8) | buffer[1]) / 1.2;
        rt_memset(buff, 20, 0);
        rt_sprintf(buff, "light : %d lx      ", light);
        OLED_ShowString(10, 5, buff);
        rt_thread_mdelay(150);
    }
}

实验效果

实时读取环境的温度和光照强度,正值夜晚光照强度在0-100 lx范围内

实时效果:当温度传感器接触人体时,测量到的温度在不停上升

注意事项

这里有三个关键的模块,连接线比较复杂

  • 千万不要接错电源和地
  • i2c不能接错数据线和时钟线,spi接线也不例外
  • 读取不到数据可以借助一些工具排查一下,比如i2c-tools、逻辑分析仪
阅读剩余
THE END