使用Python调用NI DAQmx

一、硬件： 笔记本电脑Windows 10系统 NI USB-6000 二、软件： （1）Python版本3.7如下 （2）NI DAQmx16.0 查看板卡对应的设备名称； （3）安装Python下的DAQmx，使用pip install DAQmx进行安装。 三、参考链接： NI DAQmx Python API说明参考： https://nidaqmx-python.readthedocs.io/en/latest/index.html Control NI DAQ Device with Python and NI DAQmx https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z0000019Pf1SAE&l=zh-CN 四、代码示例

import nidaqmx import pprint import numpy as np from matplotlib import pyplot as plt pp = pprint.PrettyPrinter(indent=4) with nidaqmx.Task() as task: task.ai_channels.add_ai_voltage_chan("Dev1/ai0") print('1 Channel 1 Sample Read: ') data = task.read() pp.pprint(data) data = task.read(number_of_samples_per_channel=1) pp.pprint(data) print('1 Channel N Samples Read: ') data = task.read(number_of_samples_per_channel=10) x=np.arange(0,len(data)) pp.pprint(data) plt.plot(x,data) task.ai_channels.add_ai_voltage_chan("Dev1/ai1") print('N Channel 1 Sample Read: ') data = task.read() pp.pprint(data) print('N Channel N Samples Read: ') data = task.read(number_of_samples_per_channel=2) pp.pprint(data)

执行结果如下： 五、示例2：

import nidaqmx import tkinter as tk from tkinter import ttk import matplotlib matplotlib.use("TkAgg") from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg from matplotlib.figure import Figure class voltageContinuousInput(tk.Frame): def __init__(self, master): tk.Frame.__init__(self, master) #Configure root tk class self.master = master self.master.title("Voltage - Continuous Input") self.master.iconbitmap("Voltage - Continuous Input.ico") self.master.geometry("1100x600") self.create_widgets() self.pack() self.run = False def create_widgets(self): #The main frame is made up of three subframes self.channelSettingsFrame = channelSettings(self, title ="Channel Settings") self.channelSettingsFrame.grid(row=0, column=1, sticky="ew", pady=(20,0), padx=(20,20), ipady=10) self.inputSettingsFrame = inputSettings(self, title="Input Settings") self.inputSettingsFrame.grid(row=1, column=1, pady=(20,0), padx=(20,20), ipady=10) self.graphDataFrame = graphData(self) self.graphDataFrame.grid(row=0, rowspan=2, column=2, pady=(20,0), ipady=10) def startTask(self): #Prevent user from starting task a second time self.inputSettingsFrame.startButton['state'] = 'disabled' #Shared flag to alert task if it should stop self.continueRunning = True #Get task settings from the user physicalChannel = self.channelSettingsFrame.physicalChannelEntry.get() maxVoltage = int(self.channelSettingsFrame.maxVoltageEntry.get()) minVoltage = int(self.channelSettingsFrame.minVoltageEntry.get()) sampleRate = int(self.inputSettingsFrame.sampleRateEntry.get()) self.numberOfSamples = int(self.inputSettingsFrame.numberOfSamplesEntry.get()) #Have to share number of samples with runTask #Create and start task self.task = nidaqmx.Task() self.task.ai_channels.add_ai_voltage_chan(physicalChannel, min_val=minVoltage, max_val=maxVoltage) self.task.timing.cfg_samp_clk_timing(sampleRate,sample_mode=nidaqmx.constants.AcquisitionType.CONTINUOUS,samps_per_chan=self.numberOfSamples*3) self.task.start() #spin off call to check self.master.after(10, self.runTask) def runTask(self): #Check if task needs to update the graph samplesAvailable = self.task._in_stream.avail_samp_per_chan if(samplesAvailable >= self.numberOfSamples): vals = self.task.read(self.numberOfSamples) self.graphDataFrame.ax.cla() self.graphDataFrame.ax.set_title("Acquired Data") self.graphDataFrame.ax.plot(vals) self.graphDataFrame.graph.draw() #check if the task should sleep or stop if(self.continueRunning): self.master.after(10, self.runTask) else: self.task.stop() self.task.close() self.inputSettingsFrame.startButton['state'] = 'enabled' def stopTask(self): #call back for the "stop task" button self.continueRunning = False class channelSettings(tk.LabelFrame): def __init__(self, parent, title): tk.LabelFrame.__init__(self, parent, text=title, labelanchor='n') self.parent = parent self.grid_columnconfigure(0, weight=1) self.xPadding = (30,30) self.create_widgets() def create_widgets(self): self.physicalChannelLabel = ttk.Label(self, text="Physical Channel") self.physicalChannelLabel.grid(row=0,sticky='w', padx=self.xPadding, pady=(10,0)) self.physicalChannelEntry = ttk.Entry(self) self.physicalChannelEntry.insert(0, "Dev1/ai0") self.physicalChannelEntry.grid(row=1, sticky="ew", padx=self.xPadding) self.maxVoltageLabel = ttk.Label(self, text="Max Voltage") self.maxVoltageLabel.grid(row=2,sticky='w', padx=self.xPadding, pady=(10,0)) self.maxVoltageEntry = ttk.Entry(self) self.maxVoltageEntry.insert(0, "10") self.maxVoltageEntry.grid(row=3, sticky="ew", padx=self.xPadding) self.minVoltageLabel = ttk.Label(self, text="Min Voltage") self.minVoltageLabel.grid(row=4, sticky='w', padx=self.xPadding,pady=(10,0)) self.minVoltageEntry = ttk.Entry(self) self.minVoltageEntry.insert(0, "-10") self.minVoltageEntry.grid(row=5, sticky="ew", padx=self.xPadding,pady=(0,10)) class inputSettings(tk.LabelFrame): def __init__(self, parent, title): tk.LabelFrame.__init__(self, parent, text=title, labelanchor='n') self.parent = parent self.xPadding = (30,30) self.create_widgets() def create_widgets(self): self.sampleRateLabel = ttk.Label(self, text="Sample Rate") self.sampleRateLabel.grid(row=0, column=0, columnspan=2, sticky='w', padx=self.xPadding, pady=(10,0)) self.sampleRateEntry = ttk.Entry(self) self.sampleRateEntry.insert(0, "1000") self.sampleRateEntry.grid(row=1, column=0, columnspan=2, sticky='ew', padx=self.xPadding) self.numberOfSamplesLabel = ttk.Label(self, text="Number of Samples") self.numberOfSamplesLabel.grid(row=2, column=0, columnspan=2, sticky='w', padx=self.xPadding, pady=(10,0)) self.numberOfSamplesEntry = ttk.Entry(self) self.numberOfSamplesEntry.insert(0, "100") self.numberOfSamplesEntry.grid(row=3, column=0, columnspan=2, sticky='ew', padx=self.xPadding) self.startButton = ttk.Button(self, text="Start Task", command=self.parent.startTask) self.startButton.grid(row=4, column=0, sticky='w', padx=self.xPadding, pady=(10,0)) self.stopButton = ttk.Button(self, text="Stop Task", command=self.parent.stopTask) self.stopButton.grid(row=4, column=1, sticky='e', padx=self.xPadding, pady=(10,0)) class graphData(tk.Frame): def __init__(self, parent): tk.Frame.__init__(self, parent) self.create_widgets() def create_widgets(self): self.graphTitle = ttk.Label(self, text="Voltage Input") self.fig = Figure(figsize=(7,5), dpi=100) self.ax = self.fig.add_subplot(1,1,1) self.ax.set_title("Acquired Data") self.graph = FigureCanvasTkAgg(self.fig, self) self.graph.draw() self.graph.get_tk_widget().pack() #Creates the tk class and primary application "voltageContinuousInput" root = tk.Tk() app = voltageContinuousInput(root) #start the application app.mainloop()

运行结果如下： 六、其他代码参见以下： 在本论坛搜索：nidaqmx-python-master.zip