1. 三轴加速度计MMA7660

pyBoard中内置了一个三轴加速度计MMA7660，输出x,y,z三个轴的加速度，测量范围大概是-1.5g到1.5g。pyb中关于MMA7660的构造函数和使用方法如下所示：

示例代码为：

import pyb
from machine import Pin,I2C

#初始化相关模块
accel = pyb.Accel()

#测量结果
x = accel.x()
y = accel.y()
z = accel.z()

2. 温度传感器DS18B20

DS18B20是常用的温度传感器，它是单总线式传感器，连接原理图如下所示：

pyBoard中单总线模块文件是"onewire.py"，DS18B20模块文件是"DS18X20.py",单总线模块的构造函数和使用方法为：

DS18B20的模块的构造函数和使用方法为：

温度传感器代码示例：

#引用相关模块
from pyb import delay
from machine import Pin,I2C
from onewire import OneWire
from ds18x20 import DS18X20

#初始化DS18B20
ow= OneWire(Pin('X11')) #使能单总线
ds = DS18X20(ow)        #传感器是DS18B20
rom = ds.scan()         #扫描单总线上的传感器地址，支持多个传感器同时连接

while True:
	ds.convert_temp()   #温度采集转换
	temp = ds.read_temp(rom[0]) #温度显示,rom[0]为第1个DS18B20

3. 温湿度传感器DHT11

DHT11也是常见的和常用的湿度传感器，其也是单总线传感器。

pyBoard中dht11.py文件中的构造函数和使用方法为：

DHT11的示例代码为：

#引入相关模块
from pyb import delay
from machine import Pin,I2C
from dht import DHT11

#创建DTH11对象dt
dt=DHT11(Pin('X12'))
delay(1000)          #首次启动停顿1秒然传感器稳定

while True:
	dt.measure()         #温湿度采集
	te=dt.temperature()  #获取温度值
	dh=dt.humidity()     #获取湿度值

4. 气压传感器BMP280

BMP280是常用的气压传感器，我们需要编写BMP280的驱动文件“bmp280.py”,该模块文件中的构造函数和使用方法为：

BMP280的代码示例为：

import pyb
import bmp280
from machine import Pin,I2C

#初始化BMP280，I2C接口2
BMP = bmp280.BMP280(I2C(2))

#测量结果
Tem = BMP.getTemp()
Pre = BMP.getPress()
Alt = BMP.getAltitude()

bmp280.py中的代码为：

BMP280_I2C_ADDR = const(0x76)

class BMP280():
    def __init__(self, i2c):
        self.i2c = i2c
        self.dig_T1 = self.get2Reg(0x88)
        self.dig_T2 = self.short(self.get2Reg(0x8A))
        self.dig_T3 = self.short(self.get2Reg(0x8C))
        self.dig_P1 = self.get2Reg(0x8E)
        self.dig_P2 = self.short(self.get2Reg(0x90))
        self.dig_P3 = self.short(self.get2Reg(0x92))
        self.dig_P4 = self.short(self.get2Reg(0x94))
        self.dig_P5 = self.short(self.get2Reg(0x96))
        self.dig_P6 = self.short(self.get2Reg(0x98))
        self.dig_P7 = self.short(self.get2Reg(0x9A))
        self.dig_P8 = self.short(self.get2Reg(0x9C))
        self.dig_P9 = self.short(self.get2Reg(0x9E))
        self.mode = 3
        self.osrs_p = 3
        self.osrs_t = 1
        self.setReg(0xF4, 0x2F)
        self.setReg(0xF5, 0x0C)
        self.filter = 3
        self.T = 0
        self.P = 0
        self.version = '1.0'

    def	short(self,	dat):
        if dat > 32767:
            return dat - 65536
        else:
            return dat
	
    # set reg
    def	setReg(self, reg, dat):
        self.i2c.writeto(BMP280_I2C_ADDR, bytearray([reg, dat]))
		
    # get reg
    def	getReg(self, reg):
        self.i2c.writeto(BMP280_I2C_ADDR, bytearray([reg]))
        t =	self.i2c.readfrom(BMP280_I2C_ADDR, 1)
        return t[0]
	
    # get two reg
    def	get2Reg(self, reg):
        self.i2c.writeto(BMP280_I2C_ADDR, bytearray([reg]))
        t =	self.i2c.readfrom(BMP280_I2C_ADDR, 2)
        return t[0] + t[1]*256

    def get(self):
        adc_T = (self.getReg(0xFA)<<12) + (self.getReg(0xFB)<<4) + (self.getReg(0xFC)>>4)
        var1 = (((adc_T>>3)-(self.dig_T1<<1))*self.dig_T2)>>11
        var2 = (((((adc_T>>4)-self.dig_T1)*((adc_T>>4) - self.dig_T1))>>12)*self.dig_T3)>>14
        t = var1+var2
        self.T = ((t * 5 + 128) >> 8)/100
        var1 = (t>>1) - 64000
        var2 = (((var1>>2) * (var1>>2)) >> 11 ) * self.dig_P6
        var2 = var2 + ((var1*self.dig_P5)<<1)
        var2 = (var2>>2)+(self.dig_P4<<16)
        var1 = (((self.dig_P3*((var1>>2)*(var1>>2))>>13)>>3) + (((self.dig_P2) * var1)>>1))>>18
        var1 = ((32768+var1)*self.dig_P1)>>15
        if var1 == 0:
            return  # avoid exception caused by division by zero
        adc_P = (self.getReg(0xF7)<<12) + (self.getReg(0xF8)<<4) + (self.getReg(0xF9)>>4)
        p=((1048576-adc_P)-(var2>>12))*3125
        if p < 0x80000000:
            p = (p << 1) // var1
        else:
            p = (p // var1) * 2
        var1 = (self.dig_P9 * (((p>>3)*(p>>3))>>13))>>12
        var2 = (((p>>2)) * self.dig_P8)>>13
        self.P = p + ((var1 + var2 + self.dig_P7) >> 4)
        return [self.T, self.P]

    # get Temperature in Celsius
    def getTemp(self):
        self.get()
        return self.T

    # get Pressure in Pa
    def getPress(self):
        self.get()
        return self.P

    # Calculating absolute altitude
    def	getAltitude(self):
        return '%.2f'%(44330*(1-(self.getPress()/101325)**(1/5.256)))

    # sleep mode
    def poweroff(self):
        self.setReg(0xF4, 0)

    # normal mode
    def poweron(self):
        self.setReg(0xF4, 0x2F)