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我是Python新手，目前正在开发Pi 3 mod b上的项目。我使用Adafruit ADC1015来转换模拟信号。然而，即使我有代码来获得一些电压测量，我得到一个“AttributeError：'int'对象没有属性'readADCSingleEnded'”的错误。Adafruit ADC和Python属性错误
要解释的是，Python脚本我试图运行如下：
#!/usr/bin/python
import time, signal, sys
from Adafruit_ADS1x15 import ADS1x15
def signal_handler(signal, frame):
print 'You pressed Ctrl+C!'
sys.exit(0)
signal.signal(signal.SIGINT, signal_handler)
ADS1015 = 0x00
ADS1115 = 0x01
gain = 4096 # +/- 4.096V
sps = 250 # 250 samples per second
# Initialise the ADC using the default mode (use default I2C address)
# Set this to ADS1015 or ADS1115 depending on the ADC you are using!
adc = ADS1015(ic=ADS1015)
# Read channel 0 in single-ended mode using the settings above
volts=adc.readADCSingleEnded(0, gain, sps)/1000
# To read channel 3 in single-ended mode, +/- 1.024V, 860 sps use:
# volts = adc.readADCSingleEnded(3, 1024, 860)
print "%.6f" % (volts)
的“ADS1x15”文件我们导入包含与错误的下面的代码：
# Constructor
def __init__(self, address=0x48, ic=__IC_ADS1015, debug=False):
# Depending on if you have an old or a new Raspberry Pi, you
# may need to change the I2C bus. Older Pis use SMBus 0,
# whereas new Pis use SMBus 1. If you see an error like:
# 'Error accessing 0x48: Check your I2C address '
# change the SMBus number in the initializer below!
self.i2c = Adafruit_I2C(address)
self.address = address
self.debug = debug
# Make sure the IC specified is valid
if ((ic < self.__IC_ADS1015) | (ic > self.__IC_ADS1115)):
if (self.debug):
print "ADS1x15: Invalid IC specfied: %h" % ic
return -1
else:
self.ic = ic
# Set pga value, so that getLastConversionResult() can use it,
# any function that accepts a pga value must update this.
self.pga = 6144
def readADCSingleEnded(self, channel=0, pga=6144, sps=250):
"Gets a single-ended ADC reading from the specified channel in mV. \
The sample rate for this mode (single-shot) can be used to lower the noise \
(low sps) or to lower the power consumption (high sps) by duty cycling, \
see datasheet page 14 for more info. \
The pga must be given in mV, see page 13 for the supported values."
# With invalid channel return -1
if (channel > 3):
if (self.debug):
print "ADS1x15: Invalid channel specified: %d" % channel
return -1
# Disable comparator, Non-latching, Alert/Rdy active low
# traditional comparator, single-shot mode
config = self.__ADS1015_REG_CONFIG_CQUE_NONE | \
self.__ADS1015_REG_CONFIG_CLAT_NONLAT | \
self.__ADS1015_REG_CONFIG_CPOL_ACTVLOW | \
self.__ADS1015_REG_CONFIG_CMODE_TRAD | \
self.__ADS1015_REG_CONFIG_MODE_SINGLE
# Set sample per seconds, defaults to 250sps
# If sps is in the dictionary (defined in init) it returns the value of the constant
# othewise it returns the value for 250sps. This saves a lot of if/elif/else code!
if (self.ic == self.__IC_ADS1015):
config |= self.spsADS1015.setdefault(sps, self.__ADS1015_REG_CONFIG_DR_1600SPS)
else:
if ((sps not in self.spsADS1115) & self.debug):
print "ADS1x15: Invalid pga specified: %d, using 6144mV" % sps
config |= self.spsADS1115.setdefault(sps, self.__ADS1115_REG_CONFIG_DR_250SPS)
# Set PGA/voltage range, defaults to +-6.144V
if ((pga not in self.pgaADS1x15) & self.debug):
print "ADS1x15: Invalid pga specified: %d, using 6144mV" % sps
config |= self.pgaADS1x15.setdefault(pga, self.__ADS1015_REG_CONFIG_PGA_6_144V)
self.pga = pga
# Set the channel to be converted
if channel == 3:
config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_3
elif channel == 2:
config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_2
elif channel == 1:
config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_1
else:
config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_0
# Set 'start single-conversion' bit
config |= self.__ADS1015_REG_CONFIG_OS_SINGLE
# Write config register to the ADC
bytes = [(config >> 8) & 0xFF, config & 0xFF]
self.i2c.writeList(self.__ADS1015_REG_POINTER_CONFIG, bytes)
# Wait for the ADC conversion to complete
# The minimum delay depends on the sps: delay >= 1/sps
# We add 0.1ms to be sure
delay = 1.0/sps+0.0001
time.sleep(delay)
# Read the conversion results
result = self.i2c.readList(self.__ADS1015_REG_POINTER_CONVERT, 2)
if (self.ic == self.__IC_ADS1015):
# Shift right 4 bits for the 12-bit ADS1015 and convert to mV
return (((result[0] << 8) | (result[1] & 0xFF)) >> 4)*pga/2048.0
else:
# Return a mV value for the ADS1115
# (Take signed values into account as well)
val = (result[0] << 8) | (result[1])
if val > 0x7FFF:
return (val - 0xFFFF)*pga/32768.0
else:
return ((result[0] << 8) | (result[1]))*pga/32768.0
我相信这会运行得非常好，因为它与ADC有关，但我还没有设法解决这个问题，即使我尝试了很多。