Take4

Hi @reddish The dwf package seems very useful. I installed it. Thanks for the useful information.

Hi @attila Thank you for your help. I set analog input to 2V by dwf.FDwfAnalogInChannelRangeSet(hdwf, channel#, c_double(2.0)) and got the waveform below. The new version looks useful, I'll consider updating. One more question, can the sample mode be changed from the SDK? Thank you.

from ctypes import * from dwfconstants import * import math import time import matplotlib.pyplot as plt import sys import numpy import csv if sys.platform.startswith("win"): dwf = cdll.dwf elif sys.platform.startswith("darwin"): dwf = cdll.LoadLibrary("/Library/Frameworks/dwf.framework/dwf") else: dwf = cdll.LoadLibrary("libdwf.so") #--------declare ctype variables---------- hdwf = c_int() sts = c_byte() hzAcq = c_double(1000000) N = 262144 rgdSamples1 = (c_double*N)() rgdSamples2 = (c_double*N)() cAvailable = c_int() cLost = c_int() cCorrupted = c_int() fLost = 0 fCorrupted = 0 #-----------print(DWF version)--------------- version = create_string_buffer(16) dwf.FDwfGetVersion(version) print("DWF Version: "+str(version.value)) #---------------open device------------------- print("Opening first device") dwf.FDwfDeviceOpen(c_int(-1), byref(hdwf)) if hdwf.value == hdwfNone.value: szerr = create_string_buffer(512) dwf.FDwfGetLastErrorMsg(szerr) print(str(szerr.value)) print("failed to open device") quit() #------------------------------------Waveform setting------------------------------------------ print("Generating sine wave...") dwf.FDwfAnalogOutNodeEnableSet(hdwf, c_int(0), AnalogOutNodeCarrier, c_int(1)) dwf.FDwfAnalogOutNodeFunctionSet(hdwf, c_int(0), AnalogOutNodeCarrier, funcSine) dwf.FDwfAnalogOutNodeFrequencySet(hdwf, c_int(0), AnalogOutNodeCarrier, c_double(500)) dwf.FDwfAnalogOutNodeAmplitudeSet(hdwf, c_int(0), AnalogOutNodeCarrier, c_double(0.2)) dwf.FDwfAnalogOutConfigure(hdwf, c_int(0), c_int(1)) #---------------------------------set up for aquisition---------------------------------------- dwf.FDwfAnalogInChannelEnableSet(hdwf, c_int(-1), c_int(1)) dwf.FDwfAnalogInChannelCouplingSet(hdwf, c_int(-1), c_int(1)) dwf.FDwfAnalogInAcquisitionModeSet(hdwf, acqmodeRecord) dwf.FDwfAnalogInFrequencySet(hdwf, hzAcq) dwf.FDwfAnalogInRecordLengthSet(hdwf, c_double(N/hzAcq.value)) # -1 infinite record length #wait at least 2 seconds for the offset to stabilize time.sleep(2) print("Starting oscilloscope") dwf.FDwfAnalogInConfigure(hdwf, c_int(0), c_int(1)) cSamples = 0 Channel1_data = [] Channel2_data = [] #---------------------------------------------Start aquisition------------------------------------------------- while cSamples < N: dwf.FDwfAnalogInStatus(hdwf, c_int(1), byref(sts)) if cSamples == 0 and (sts == DwfStateConfig or sts == DwfStatePrefill or sts == DwfStateArmed) : # Acquisition not yet started. continue dwf.FDwfAnalogInStatusRecord(hdwf, byref(cAvailable), byref(cLost), byref(cCorrupted)) cSamples += cLost.value if cLost.value : fLost = 1 if cCorrupted.value : fCorrupted = 1 if cAvailable.value==0 : continue if cSamples+cAvailable.value > N : cAvailable = c_int(N-cSamples) dwf.FDwfAnalogInStatusData(hdwf, c_int(0), byref(rgdSamples1, sizeof(c_double)*cSamples), cAvailable) # get channel 1 data dwf.FDwfAnalogInStatusData(hdwf, c_int(1), byref(rgdSamples2, sizeof(c_double)*cSamples), cAvailable) # get channel 2 data cSamples += cAvailable.value dwf.FDwfAnalogOutReset(hdwf, c_int(0)) dwf.FDwfDeviceCloseAll() print("Recording done") if fLost: print("Samples were lost! Reduce frequency") if fCorrupted: print("Samples could be corrupted! Reduce frequency") #aquiring data length data_length = len(rgdSamples1) #Storing data in arrays for i in range(data_length): Channel1_data.append(rgdSamples1[i]) Channel2_data.append(rgdSamples2[i]) #--------------------------stored in csv file------------------------------ with open('record.csv', mode = 'w', newline = '') as file: writer = csv.writer(file) for item1, item2 in zip(Channel1_data, Channel2_data): writer.writerow([item1, item2]) plt.plot(numpy.fromiter(rgdSamples1, dtype = numpy.float64)) plt.plot(numpy.fromiter(rgdSamples2, dtype = numpy.float64)) plt.show() The top waveform was obtained from the Waveform application and the bottom waveform was obtained using the Waveform SDK. Hello, I have a question regarding the behavior of WaveForm SDK when acquiring waveforms. I use an ADP3450 and I want to get the same waveforms in the WaveForms app and the WaveForm SDK, but this makes a difference. Is this a difference between the settings in the SDK and the application? Can someone please help me with a solution to this? I attach the program of my python and the screen shot of the setting for acquiring waveforms in the application. Below is a screen shot of the settings for waveform acquisition in the application. This is the entire WaveForms setup screen. And, this image is the setting for acquiring waveforms. Thank you.

Hi @attila Thank you for the answer. I checked it while switching between DC and AC mode and it worked fine. Thank you for your help.

from ctypes import * from dwfconstants import * import math import time import matplotlib.pyplot as plt import sys import numpy import csv if sys.platform.startswith("win"): dwf = cdll.dwf elif sys.platform.startswith("darwin"): dwf = cdll.LoadLibrary("/Library/Frameworks/dwf.framework/dwf") else: dwf = cdll.LoadLibrary("libdwf.so") #--------declare ctype variables---------- hdwf = c_int() sts = c_byte() hzAcq = c_double(1000000) N = 262144 rgdSamples1 = (c_double*N)() rgdSamples2 = (c_double*N)() cAvailable = c_int() cLost = c_int() cCorrupted = c_int() fLost = 0 fCorrupted = 0 #-----------print(DWF version)--------------- version = create_string_buffer(16) dwf.FDwfGetVersion(version) print("DWF Version: "+str(version.value)) #---------------open device------------------- print("Opening first device") dwf.FDwfDeviceOpen(c_int(-1), byref(hdwf)) if hdwf.value == hdwfNone.value: szerr = create_string_buffer(512) dwf.FDwfGetLastErrorMsg(szerr) print(str(szerr.value)) print("failed to open device") quit() #------------------------------------Waveform setting------------------------------------------ print("Generating sine wave...") dwf.FDwfAnalogOutNodeEnableSet(hdwf, c_int(0), AnalogOutNodeCarrier, c_int(1)) dwf.FDwfAnalogOutNodeFunctionSet(hdwf, c_int(0), AnalogOutNodeCarrier, funcSine) dwf.FDwfAnalogOutNodeFrequencySet(hdwf, c_int(0), AnalogOutNodeCarrier, c_double(500)) dwf.FDwfAnalogOutNodeAmplitudeSet(hdwf, c_int(0), AnalogOutNodeCarrier, c_double(0.2)) dwf.FDwfAnalogOutConfigure(hdwf, c_int(0), c_int(1)) #---------------------------------set up for aquisition---------------------------------------- dwf.FDwfAnalogInChannelEnableSet(hdwf, c_int(-1), c_int(1)) dwf.FDwfAnalogInChannelCouplingSet(hdwf, c_int(-1), c_int(1)) dwf.FDwfAnalogInAcquisitionModeSet(hdwf, acqmodeRecord) dwf.FDwfAnalogInFrequencySet(hdwf, hzAcq) dwf.FDwfAnalogInRecordLengthSet(hdwf, c_double(N/hzAcq.value)) # -1 infinite record length #wait at least 2 seconds for the offset to stabilize time.sleep(2) print("Starting oscilloscope") dwf.FDwfAnalogInConfigure(hdwf, c_int(0), c_int(1)) cSamples = 0 Channel1_data = [] Channel2_data = [] #---------------------------------------------Start aquisition------------------------------------------------- while cSamples < N: dwf.FDwfAnalogInStatus(hdwf, c_int(1), byref(sts)) if cSamples == 0 and (sts == DwfStateConfig or sts == DwfStatePrefill or sts == DwfStateArmed) : # Acquisition not yet started. continue dwf.FDwfAnalogInStatusRecord(hdwf, byref(cAvailable), byref(cLost), byref(cCorrupted)) cSamples += cLost.value if cLost.value : fLost = 1 if cCorrupted.value : fCorrupted = 1 if cAvailable.value==0 : continue if cSamples+cAvailable.value > N : cAvailable = c_int(N-cSamples) dwf.FDwfAnalogInStatusData(hdwf, c_int(0), byref(rgdSamples1, sizeof(c_double)*cSamples), cAvailable) # get channel 1 data dwf.FDwfAnalogInStatusData(hdwf, c_int(1), byref(rgdSamples2, sizeof(c_double)*cSamples), cAvailable) # get channel 2 data cSamples += cAvailable.value dwf.FDwfAnalogOutReset(hdwf, c_int(0)) dwf.FDwfDeviceCloseAll() print("Recording done") if fLost: print("Samples were lost! Reduce frequency") if fCorrupted: print("Samples could be corrupted! Reduce frequency") #aquiring data length data_length = len(rgdSamples1) #Storing data in arrays for i in range(data_length): Channel1_data.append(rgdSamples1[i]) Channel2_data.append(rgdSamples2[i]) #--------------------------stored in csv file------------------------------ with open('record.csv', mode = 'w', newline = '') as file: writer = csv.writer(file) for item1, item2 in zip(Channel1_data, Channel2_data): writer.writerow([item1, item2]) plt.plot(numpy.fromiter(rgdSamples1, dtype = numpy.float64)) plt.plot(numpy.fromiter(rgdSamples2, dtype = numpy.float64)) plt.show() Hello, I have a question about programming with Waveform SDK. I use an ADP3450 and I want to change the coupling of the Input channels from DC to AC. I added to the program the command below dwf.FDwfAnalogInChannelCouplingSet(hdwf, c_int(-1), c_int(1)) ,but it didn't work. Could somebody tell me how to get the program to work properly? I attach the program of my python. Thank you.