Raspberry Pi 4 VL805 bulk transfer problem

[charkster]

I am having a problem with query_binary_values() and read_raw() when downloading waveform or csv data from my Rigol DS1054Z. These commands run just fine on my RPi3, RPi2 and PC, but with the latest RPi4 (and the VL805) I am seeing errors.

Here is what I see from query_binary_values():

  File "test_print_screen.py", line 6, in <module>
    scope.write_screen_capture()
  File "/home/pi/python_code/rigol/rigol_ds1054z.py", line 120, in write_screen_capture
    raw_data_list = self.oscilloscope.query_binary_values(':DISP:DATA? ON,OFF,PNG')
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa/resources/messagebased.py", line 703, in query_binary_values
    data_points, chunk_size)
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa/resources/messagebased.py", line 481, in read_binary_values
    block = self._read_raw(chunk_size)
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa/resources/messagebased.py", line 387, in _read_raw
    chunk, status = self.visalib.read(self.session, size)
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/highlevel.py", line 345, in read
    ret = self.sessions[session].read(count)
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/usb.py", line 111, in read
    usb.USBError)
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/sessions.py", line 477, in _read
    current = reader()
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/usb.py", line 105, in <lambda>
    return self._read(lambda: self.interface.read(count),
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/protocols/usbtmc.py", line 338, in read
    response = BulkInMessage.from_bytes(resp)
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/protocols/usbtmc.py", line 108, in from_bytes
    assert msgid == MsgID.dev_dep_msg_in
AssertionError

Here is what I see from read_raw():

Traceback (most recent call last):
  File "test_print_screen.py", line 6, in <module>
    scope.write_screen_capture()
  File "/home/pi/python_code/rigol/rigol_ds1054z.py", line 124, in write_screen_capture
    raw_data = self.oscilloscope.read_raw()[11:] # strip off first 11 bytes
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa/resources/messagebased.py", line 364, in read_raw
    return bytes(self._read_raw(size))
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa/resources/messagebased.py", line 387, in _read_raw
    chunk, status = self.visalib.read(self.session, size)
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/highlevel.py", line 345, in read
    ret = self.sessions[session].read(count)
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/usb.py", line 111, in read
    usb.USBError)
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/sessions.py", line 477, in _read
    current = reader()
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/usb.py", line 105, in <lambda>
    return self._read(lambda: self.interface.read(count),
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/protocols/usbtmc.py", line 338, in read
    response = BulkInMessage.from_bytes(resp)
  File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/protocols/usbtmc.py", line 108, in from_bytes
    assert msgid == MsgID.dev_dep_msg_in
AssertionError

If I wait one second after sending my write(':DISP:DATA? ON,OFF,PNG') command, I don't get any errors, but I only download 41bytes of data (when expecting 30KB).

Is this an issue with the VL805?
I suspect this is not a pyvisa issue, but a problem with bulk transfers with the VL805.

[MatthieuDartiailh]

You can try running using pyvisa-py master. Rigol instruments are known to implement the USBTMC protocol in a nor fully rigorous manner and the master can circumvent that. Let me know if you get it to work.

[charkster]

Hi Matthieu, Thank you for the quick response. I installed the master version of pyvisa-py and things actually got worse. Still had the issue on the RPi4, but RPi3 broke also. Was I supposed to upgrade to the master version of pyvisa too? I will just keep using my older raspberry pi 3 as pyvisa-py is working just fine with it. Thank you for this great software, it saves me a lot of time. -Chark Stanford

…

On Tue, Sep 3, 2019, 7:29 PM Matthieu Dartiailh ***@***.***> wrote: You can try running using pyvisa-py master. Rigol instruments are known to implement the USBTMC protocol in a nor fully rigorous manner and the master can circumvent that. Let me know if you get it to work. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#458?email_source=notifications&email_token=AHQZG6BVBW62JJAKI7IBSNTQH4MOZA5CNFSM4ITMTEW2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD52EGEQ#issuecomment-527713042>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AHQZG6B4QRSMRKJUBSYR7JDQH4MOZANCNFSM4ITMTEWQ> .

[MatthieuDartiailh]

Could you post the traceback you get on your raspberry 3 ?

[charkster]

Hi Matthieu, Here is the visa.log_to_screen() traceback for the successful case (RPi3): 2019-09-04 22:17:50,002 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success_max_count_read: 1073676294>) Scope information: RIGOL TECHNOLOGIES,DS1104Z,DS1ZA192107675,00.04.04.SP3 2019-09-04 22:17:53,022 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success_max_count_read: 1073676294>) Wrote screen capture to filename "rigol_2019-09-04_22-17-53.png" 2019-09-04 22:17:58,126 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - closing 2019-09-04 22:17:58,128 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - is closed Here is my python script: class rigol_ds1054z: # Constructor def __init__(self, debug=False): resources = visa.ResourceManager('@py') # insert your device here # resources.list_resources() will show you the USB resource to put below self.oscilloscope = resources.open_resource('USB0::6833::1230::DS1ZA192107675::0::INSTR') self.debug = debug if (debug): visa.log_to_screen() def print_info(self): self.oscilloscope.write('*IDN?') fullreading = self.oscilloscope.read_raw() readinglines = fullreading.splitlines() print("Scope information: " + readinglines[0]) * time.sleep(2)* def write_screen_capture(self, filename=''): self.oscilloscope.write(':DISP:DATA? ON,OFF,PNG') time.sleep(1) raw_data = self.oscilloscope.read_raw()[11:] # strip off first 11 bytes # save image file if (filename == ''): filename = "rigol_" + datetime.datetime.now().strftime("%Y-%m-%d_%H-%M-%S") +".png" fid = open(filename, 'wb') fid.write(raw_data) fid.close() print ("Wrote screen capture to filename " + '\"' + filename + '\"') * time.sleep(5)* from rigol_ds1054z import rigol_ds1054z scope = rigol_ds1054z(debug=True) scope.print_info() scope.write_screen_capture()

…

-Chark

On Wed, Sep 4, 2019 at 4:32 AM Matthieu Dartiailh ***@***.***> wrote: Could you post the traceback you get on your raspberry 3 ? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#458?email_source=notifications&email_token=AHQZG6APFLHJFG2FADHHUJDQH6MDZA5CNFSM4ITMTEW2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD53IMHQ#issuecomment-527861278>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AHQZG6FU4Y6V5NB4ZD7BBC3QH6MDZANCNFSM4ITMTEWQ> .

[charkster]

Hi Matthieu, Here is the traceback for the unsuccessful RPi4 case (same script as the RPi3). 2019-09-04 22:36:18,442 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success_max_count_read: 1073676294>) Scope information: RIGOL TECHNOLOGIES,DS1104Z,DS1ZA192107675,00.04.04.S 2019-09-04 22:36:20,459 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success_max_count_read: 1073676294>) Traceback (most recent call last): File "test_print_screen.py", line 6, in <module> scope.write_screen_capture() File "/home/pi/python_code/rigol/rigol_ds1054z.py", line 122, in write_screen_capture raw_data_list = self.oscilloscope.query_binary_values(':DISP:DATA? ON,OFF,PNG') File "/home/pi/.local/lib/python2.7/site-packages/pyvisa/resources/messagebased.py", line 715, in query_binary_values data_points, chunk_size) File "/home/pi/.local/lib/python2.7/site-packages/pyvisa/resources/messagebased.py", line 493, in read_binary_values block = self._read_raw(chunk_size) File "/home/pi/.local/lib/python2.7/site-packages/pyvisa/resources/messagebased.py", line 400, in _read_raw chunk, status = self.visalib.read(self.session, size) File "/usr/lib/python2.7/dist-packages/pyvisa-py/highlevel.py", line 345, in read ret = self.sessions[session].read(count) File "/usr/lib/python2.7/dist-packages/pyvisa-py/usb.py", line 111, in read usb.USBError) File "/usr/lib/python2.7/dist-packages/pyvisa-py/sessions.py", line 477, in _read current = reader() File "/usr/lib/python2.7/dist-packages/pyvisa-py/usb.py", line 105, in <lambda> return self._read(lambda: self.interface.read(count), File "/usr/lib/python2.7/dist-packages/pyvisa-py/protocols/usbtmc.py", line 338, in read response = BulkInMessage.from_bytes(resp) File "/usr/lib/python2.7/dist-packages/pyvisa-py/protocols/usbtmc.py", line 108, in from_bytes assert msgid == MsgID.dev_dep_msg_in AssertionError 2019-09-04 22:36:21,313 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - closing 2019-09-04 22:36:21,316 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - is closed

…

-Chark

On Wed, Sep 4, 2019 at 10:31 PM C Stanford ***@***.***> wrote: Hi Matthieu, Here is the visa.log_to_screen() traceback for the successful case (RPi3): 2019-09-04 22:17:50,002 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success_max_count_read: 1073676294>) Scope information: RIGOL TECHNOLOGIES,DS1104Z,DS1ZA192107675,00.04.04.SP3 2019-09-04 22:17:53,022 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success_max_count_read: 1073676294>) Wrote screen capture to filename "rigol_2019-09-04_22-17-53.png" 2019-09-04 22:17:58,126 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - closing 2019-09-04 22:17:58,128 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - is closed Here is my python script: class rigol_ds1054z: # Constructor def __init__(self, debug=False): resources = ***@***.***') # insert your device here # resources.list_resources() will show you the USB resource to put below self.oscilloscope = resources.open_resource('USB0::6833::1230::DS1ZA192107675::0::INSTR') self.debug = debug if (debug): visa.log_to_screen() def print_info(self): self.oscilloscope.write('*IDN?') fullreading = self.oscilloscope.read_raw() readinglines = fullreading.splitlines() print("Scope information: " + readinglines[0]) * time.sleep(2)* def write_screen_capture(self, filename=''): self.oscilloscope.write(':DISP:DATA? ON,OFF,PNG') time.sleep(1) raw_data = self.oscilloscope.read_raw()[11:] # strip off first 11 bytes # save image file if (filename == ''): filename = "rigol_" + datetime.datetime.now().strftime("%Y-%m-%d_%H-%M-%S") +".png" fid = open(filename, 'wb') fid.write(raw_data) fid.close() print ("Wrote screen capture to filename " + '\"' + filename + '\"') * time.sleep(5)* from rigol_ds1054z import rigol_ds1054z scope = rigol_ds1054z(debug=True) scope.print_info() scope.write_screen_capture() -Chark On Wed, Sep 4, 2019 at 4:32 AM Matthieu Dartiailh < ***@***.***> wrote: > Could you post the traceback you get on your raspberry 3 ? > > — > You are receiving this because you authored the thread. > Reply to this email directly, view it on GitHub > <#458?email_source=notifications&email_token=AHQZG6APFLHJFG2FADHHUJDQH6MDZA5CNFSM4ITMTEW2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD53IMHQ#issuecomment-527861278>, > or mute the thread > <https://github.com/notifications/unsubscribe-auth/AHQZG6FU4Y6V5NB4ZD7BBC3QH6MDZANCNFSM4ITMTEWQ> > . >

[MatthieuDartiailh]

Could you also post the traceback you get on pyvisa-py master ? I would prefer to avoid breaking your code with the new release.

[charkster]

Hi Matthieu, Here is the traceback on my good RPi3 after upgrading pyvisa-py to 0.4.0.dev0. 2019-09-05 19:36:04,574 - pyvisa - ERROR - Unknown attribute 1073676310 (0x3fff0016 - VI_ATTR_SEND_END_EN) Traceback (most recent call last): File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/sessions.py", line 377, in get_attribute return self._get_attribute(attribute) File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/usb.py", line 160, in _get_attribute raise UnknownAttribute(attribute) UnknownAttribute: Unknown attribute 1073676310 (0x3fff0016 - VI_ATTR_SEND_END_EN) 2019-09-05 19:36:04,581 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success_max_count_read: 1073676294>) 2019-09-05 19:36:04,583 - pyvisa - ERROR - Unknown attribute 1073676312 (0x3fff0018 - VI_ATTR_TERMCHAR) Traceback (most recent call last): File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/sessions.py", line 377, in get_attribute return self._get_attribute(attribute) File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/usb.py", line 160, in _get_attribute raise UnknownAttribute(attribute) UnknownAttribute: Unknown attribute 1073676312 (0x3fff0018 - VI_ATTR_TERMCHAR) 2019-09-05 19:36:04,584 - pyvisa - ERROR - Unknown attribute 1073676344 (0x3fff0038 - VI_ATTR_TERMCHAR_EN) Traceback (most recent call last): File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/sessions.py", line 377, in get_attribute return self._get_attribute(attribute) File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/usb.py", line 160, in _get_attribute raise UnknownAttribute(attribute) UnknownAttribute: Unknown attribute 1073676344 (0x3fff0038 - VI_ATTR_TERMCHAR_EN) Scope information: RIGOL TECHNOLOGIES,DS1104Z,DS1ZA192107675,00.04.04.SP3 2019-09-05 19:36:06,608 - pyvisa - ERROR - Unknown attribute 1073676310 (0x3fff0016 - VI_ATTR_SEND_END_EN) Traceback (most recent call last): File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/sessions.py", line 377, in get_attribute return self._get_attribute(attribute) File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/usb.py", line 160, in _get_attribute raise UnknownAttribute(attribute) UnknownAttribute: Unknown attribute 1073676310 (0x3fff0016 - VI_ATTR_SEND_END_EN) 2019-09-05 19:36:07,611 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success_max_count_read: 1073676294>) 2019-09-05 19:36:07,613 - pyvisa - ERROR - Unknown attribute 1073676312 (0x3fff0018 - VI_ATTR_TERMCHAR) Traceback (most recent call last): File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/sessions.py", line 377, in get_attribute return self._get_attribute(attribute) File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/usb.py", line 160, in _get_attribute raise UnknownAttribute(attribute) UnknownAttribute: Unknown attribute 1073676312 (0x3fff0018 - VI_ATTR_TERMCHAR) 2019-09-05 19:36:07,614 - pyvisa - ERROR - Unknown attribute 1073676344 (0x3fff0038 - VI_ATTR_TERMCHAR_EN) Traceback (most recent call last): File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/sessions.py", line 377, in get_attribute return self._get_attribute(attribute) File "/home/pi/.local/lib/python2.7/site-packages/pyvisa-py/usb.py", line 160, in _get_attribute raise UnknownAttribute(attribute) UnknownAttribute: Unknown attribute 1073676344 (0x3fff0038 - VI_ATTR_TERMCHAR_EN) Wrote screen capture to filename "rigol_2019-09-05_19-36-07.png" 2019-09-05 19:36:12,710 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - closing 2019-09-05 19:36:12,713 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - is closed

…

-Chark

On Thu, Sep 5, 2019 at 11:44 AM Matthieu Dartiailh ***@***.***> wrote: Could you also post the traceback you get on pyvisa-py master ? I would prefer to avoid breaking your code with the new release. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#458?email_source=notifications&email_token=AHQZG6DELCNCMV33ARUTRNTQIFHSBA5CNFSM4ITMTEW2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD6AJN5I#issuecomment-528520949>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AHQZG6AMLOJ3SW4MREBF56DQIFHSBANCNFSM4ITMTEWQ> .

[bjaraujo]

@charkster

Using the master branch, does it help if you change chunk_size like so?

inst.query_binary_values(':DISP:DATA? ON,OFF,PNG', chunk_size=2000*1024)

If not, maybe play around with the chunk size value (try chunk_size > or = total data size).

[MatthieuDartiailh]

Can you try pyvisa/pyvisa-py#207 ? It should the attribute issue on the USB backend.

[charkster]

Hi Matthieu,
I installed #207 and on my RPi3 and it works just fine (like it did before), but on my RPi4 I am seeing a different error now. I also turned-on the pyusb logfile and see that the RPi4 is not detaching the kernel driver. I have tried to detach it using usb.core, but have been unsuccessful (I can detach the usb port on my Ubuntu x86 PC with the same code).
It's odd that simple SCPI commands work fine, but any time I am downloading killobytes of PNG data or binary oscilloscope settings I get the unexpected MsgID.

Specifying the chunk_size also did not help (Thx bjaraujo).

2019-09-11 21:00:10,494 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success_max_count_read: 1073676294>)
/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/protocols/usbtmc.py:119: UserWarning: Unexpected MsgID format. Consider updating the device's firmware. See pyvisa/pyvisa-py#20
warnings.warn('Unexpected MsgID format. Consider updating the device's firmware. See pyvisa/pyvisa-py#20')
Traceback (most recent call last):
File "test_print_screen.py", line 15, in
scope.print_info()
File "/home/pi/python_code/rigol/rigol_ds1054z.py", line 22, in print_info
fullreading = self.oscilloscope.read_raw()
File "/home/pi/.local/lib/python2.7/site-packages/pyvisa/resources/messagebased.py", line 377, in read_raw
return bytes(self._read_raw(size))
File "/home/pi/.local/lib/python2.7/site-packages/pyvisa/resources/messagebased.py", line 400, in _read_raw
chunk, status = self.visalib.read(self.session, size)
File "/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/highlevel.py", line 329, in read
ret = self.sessions[session].read(count)
File "/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/usb.py", line 128, in read
USBTimeoutException)
File "/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/sessions.py", line 478, in _read
current = reader()
File "/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/usb.py", line 108, in _usb_reader
return self.interface.read(count)
File "/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/protocols/usbtmc.py", line 419, in read
response = BulkInMessage.from_bytes(resp)
File "/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/protocols/usbtmc.py", line 120, in from_bytes
return BulkInMessage.from_quirky(data)
File "/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/protocols/usbtmc.py", line 135, in from_quirky
if ';' in str(data):
UnicodeDecodeError: 'ascii' codec can't decode byte 0xda in position 3: ordinal not in range(128)
2019-09-11 21:00:10,562 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - closing
2019-09-11 21:00:10,565 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - is closed

[MatthieuDartiailh]

Thanks for testing. I still have no idea why the Raspberry 4 show the issue but we are doing something incorrect for quirky devices (ie which uses the wrong MsgId) in trying to convert the data to string. I pushed a temporary fix to pyvisa/pyvisa-py#207 but it would need some refinement (testing just for ; in any place looks dangerous to me). If you can test again it would be great. I will try to come with better fix in the meantime.

[charkster]

Your latest change fixed the errors but the payload was only 104 bytes (I was expecting 30k bytes). It looks like valid data is being removed. Certainly it is an improvement.

[MatthieuDartiailh]

Please note that read_raw will read till it encounters a termination character. Typically in binary block those can happen anywhere. I would recommend using read_binary_values and using the appropriate header format.

[charkster]

Hi Matthieu,
I switched to read_binary_values, but I don't know how to use "the appropriate header format".

I updated my script to be:

		self.oscilloscope.write(':DISP:DATA? ON,OFF,PNG')
		raw_data_list = self.oscilloscope.read_binary_values()

But I get this error:

2019-09-12 19:05:37,488 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success_max_count_read: 1073676294>)
/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/protocols/usbtmc.py:119: UserWarning: Unexpected MsgID format. Consider updating the device's firmware. See pyvisa/pyvisa-py#20
warnings.warn('Unexpected MsgID format. Consider updating the device's firmware. See pyvisa/pyvisa-py#20')
Scope information: RIGOL TECHNOLOGIES,DS1104Z,DS1ZA192107675,00.04.04.SP4
2019-09-12 19:05:39,499 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success_max_count_read: 1073676294>)
2019-09-12 19:05:40,292 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status None)
2019-09-12 19:05:40,293 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success: 0>)
2019-09-12 19:05:40,295 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success: 0>)
2019-09-12 19:05:40,297 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success: 0>)
2019-09-12 19:05:40,298 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success: 0>)
2019-09-12 19:05:40,299 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - reading 20480 bytes (last status <StatusCode.success: 0>)
Traceback (most recent call last):
File "test_print_screen_disable_kernel_driver.py", line 17, in
scope.write_screen_capture()
File "/home/pi/python_code/rigol/rigol_ds1054z.py", line 125, in write_screen_capture
raw_data_list = self.oscilloscope.read_binary_values()
File "/home/pi/.local/lib/python2.7/site-packages/pyvisa/resources/messagebased.py", line 520, in read_binary_values
chunk_size=chunk_size))
File "/home/pi/.local/lib/python2.7/site-packages/pyvisa/resources/messagebased.py", line 356, in read_bytes
chunk, status = self.visalib.read(self.session, size)
File "/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/highlevel.py", line 329, in read
ret = self.sessions[session].read(count)
File "/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/usb.py", line 128, in read
USBTimeoutException)
File "/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/sessions.py", line 478, in _read
current = reader()
File "/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/usb.py", line 108, in _usb_reader
return self.interface.read(count)
File "/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/protocols/usbtmc.py", line 421, in read
response = BulkInMessage.from_bytes(resp)
File "/usr/local/lib/python2.7/dist-packages/PyVISA_py-0.4.0.dev0-py2.7.egg/pyvisa-py/protocols/usbtmc.py", line 117, in from_bytes
msgid, btag, btaginverse = struct.unpack_from('BBBx', data)
struct.error: unpack_from requires a buffer of at least 4 bytes
2019-09-12 19:05:40,348 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - closing
2019-09-12 19:05:40,349 - pyvisa - DEBUG - USB0::6833::1230::DS1ZA192107675::0::INSTR - is closed