Question

我正在尝试使用来自Adafruit的产品2635的Texas Instruments HDC1008来读取温度和湿度。我使用smbus模块在rasberry pi 2上。根据TI的PDF，在获取读数时，数字将以您放在一起的两个字节发送。我发现this code执行了我正在尝试用micropython做的事情，他们有一个recv函数，它似乎只是将它们发送回一个包含两个字节的列表。 SMBus模块似乎没有任何等同于我正在尝试做的事情。这是我的一些代码。

class HDC1008:

    I2C_BUS = 1

    #Registers
    REG_TEMP =   0
    REG_HUMID =  1
    REG_CONFIG = 2

    #Configuration bits
    CFG_RST = 1<<15
    CFG_MODE_SINGLE = 0 << 12
    CFG_MODE_BOTH = 1 << 12

    ADDRESS = 0x40

    def __init__(self, bus_num=I2C_BUS):
        self.bus=smbus.SMBus(bus_num)

    def readTemperature(self):
        #configure the HDC1008 for one reading
        config = 0
        config |= self.CFG_MODE_SINGLE
        self.bus.write_byte_data(self.ADDRESS, self.REG_CONFIG, config)

        #tell the thing to take a reading
        self.bus.write_byte(self.ADDRESS, self.REG_TEMP)
        time.sleep(0.015)

        #get the reading back from the thing
        raw = self.bus.read_byte(self.ADDRESS)
        raw = (raw<<8) + self.bus.read_byte(self.ADDRESS)

        #use TI's formula to turn it into people numbers
        temperature = (raw/65536.0)*165.0 - 40

        #convert temp to f
        temperature = temperature * (9.0/5.0) + 32
        return temperature

当我从bus.read_byte获取raw的值时，我能够得到温度位的前半部分，但第二次读数只是零，大概是因为第一次交易结束了。如何在一个事务中获得两个字节？

Answer 1

tnx分享这段代码很多。我很高兴能用Python工作。

我不完全理解这个问题，我可以用我们的代码读取温度和湿度（我能找到并且有效的唯一Python代码）

我做了一点改变（让它成为一个班级）：

GROUP BY Name

在该计划中：

import smbus

class HDC: 
 #Registers
  REG_TEMP =   0
  REG_HUMID =  1
  REG_CONFIG = 2

  I2C_BUS = 2 #2 for PCDuino, 1 for PI

  #Configuration bits
  CFG_RST = 1<<15
  CFG_MODE_SINGLE = 0 << 12
  CFG_MODE_BOTH = 1 << 12

  ADDRESS = 0x40

  def __init__(self, bus_num=I2C_BUS):
     self.bus=smbus.SMBus(bus_num)

  def readTemperature(self):
    #configure the HDC1008 for one reading
    config = 0
    config |= self.CFG_MODE_SINGLE
    self.bus.write_byte_data(self.ADDRESS, self.REG_CONFIG, config)

    #tell the thing to take a reading
    self.bus.write_byte(self.ADDRESS, self.REG_TEMP)
    time.sleep(0.015)

    #get the reading back from the thing
    raw = self.bus.read_byte(self.ADDRESS)
    raw = (raw<<8) + self.bus.read_byte(self.ADDRESS)

    #use TI's formula to turn it into people numbers
    temperature = (raw/65536.0)* 165  - 40


    #convert temp to farenheid
    #temperature = temperature * (9.0/5.0) + 32
    return temperature

 def readHum(self):
    #configure the HDC1008 for one reading
    config = 0
    config |= self.CFG_MODE_SINGLE
    self.bus.write_byte_data(self.ADDRESS, self.REG_CONFIG, config)

    #tell the thing to take a reading
    self.bus.write_byte(self.ADDRESS, self.REG_HUMID)
    time.sleep(0.015)

    #get the reading back from the thing
    raw = self.bus.read_byte(self.ADDRESS)
    raw = (raw<<8) + self.bus.read_byte(self.ADDRESS)

    hum=(raw/(2.0**16))*100
    return hum

Python：我可以使用smbus模块在一个事务中读取两个字节吗？

1 个答案: