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Comments for “Fixing noisy measurements on Owon XDM2041”

Hello Petteri,
did you read out the flash of the GD32F103? And if so, could you provide me with a copy of the binary image? I have a defective device that does not correctly start up (stuck at the boot screen), which I hope to resurrect by reflashing the firmware. Maybe I'm lucky, as it is my birthday today ;-)

best regards, Andreas

— Andreas on 05.07.2021 at 09:42 (UTC)


I sent the firmware to you by email.

Though I must warn that I haven't tried reflashing my own device, so I
can't be 100% sure that the image has been extracted correctly. It looks
ok, but it is not easy to know if there might be some byte errors, as
readout protection blocks any verify functionality.

You'll probably also lose calibration by reflashing, and I don't know
how to trigger recalibration.

In my own tests I've noticed that the boot will hang with the progress
bar if the analog board is disconnected, so maybe verify those
connectors and the HY3131 power supply first.

— Petteri Aimonen on 05.07.2021 at 17:30 (UTC)


great work!
I have the same problem as Andreas, as my XDM2041 stucks at the progress bar. The µC does not try to contact the HY3131 by SPI at all. Seems the µC stucks 
in the Firmware. Can please send me the firmware, too ?


Did you get the Firmware burned into the µC ?

Thanks for your help


— Uli on 27.07.2021 at 08:05 (UTC)

I'll just summarize here what Andreas has shared by email: flashing the XDM2041 firmware on a faulty VC7055 fixed the boot problem. Copying calibration data (the last 2 kB page) also works.

— Petteri Aimonen on 07.08.2021 at 15:24 (UTC)

Hello Petteri,
I have the same problem as Andreas and Uli with my device.

@Petteri can you send me the firmware too?

Thanks for the great article and research!


— Justus Leiner on 22.08.2021 at 09:58 (UTC)

And I'm happy to report that Justus also had success with reflashing. For any others in need of the firmware & other info, I've set up this repository:

— Petteri Aimonen on 22.08.2021 at 16:39 (UTC)

To have the best of both worlds, both noiseless resistance measurement and a functioning frequency counter, you could also replace the crystal with an adjustable clock source such as the AD9851.


— Maarten Tromp on 07.11.2021 at 14:27 (UTC)

Hi. My display YYS37HV-133-A7 was damaged during transportation.
Do you know where I can bay a new display?
Do you know what kind of controller is inside the LCD?

— Vitaliy on 27.11.2021 at 11:23 (UTC)

@Vitaliy No, I haven't been able to find a place where the TFT can be bought. This page has some information on the pinout: https://github.com/PetteriAimonen/owon-xdm2041-info/tree/main/mcu_board

— Petteri Aimonen on 27.11.2021 at 11:28 (UTC)

@Petteri Thanks anyway.

— Vitaliy on 27.11.2021 at 11:39 (UTC)

I don't know if this is would be useful but this guy got a copy of a firmware update for the XDM1041 and it is posted here:

— Mick on 17.12.2021 at 18:49 (UTC)

What is interesting about the XDM firmware upgrade I mentioned above is that it includes a program to upgrade the firmware through the serial port and the instructions state that it is for the XDM2041 ("1. The PC computer and XDM2041 connected by RS232 cable").  Take a look at the readme for how to download the The firmware loader program from OWON.

— Mick on 20.12.2021 at 21:34 (UTC)

@Mick That is indeed very interesting! Have you tried it out? A capture of the serial traffic would be cool.

I decompiled the Java program, the main window is here: https://github.com/PetteriAimonen/OWON-XDM1041/blob/main/OWON%20firmware/decompiled/com/owon/uppersoft/common/comm/frame/OdpDownloadComposite.java

And the main download code is here:

There is hidden SCPI command "INT:VERSION" that sets the version number of the device. I also found that there is "INT:DOWNLOAD" that seems to enter some kind of a bootloader. Curiously I can't find that called in the decompiled code, instead it sends "start" which does nothing on my device.

— Petteri Aimonen on 21.12.2021 at 06:05 (UTC)

I have not tried it out, rumor has it I will be unwrapping a XDM2041 in few days.

— Mick on 21.12.2021 at 14:11 (UTC)

@Mick I tried it out, works on XDM2041. I made a Python script for the bootloader: https://github.com/PetteriAimonen/owon-xdm2041-info/tree/main/bootloader

— Petteri Aimonen on 09.01.2022 at 15:27 (UTC)

I got my got my XDM2041 and have been having fun with it.  I reached out to Owon via email and asked if there were any firmware updates they could share but they did not respond.  I was planning on capturing the seral port traffic and figuring our how to get the unit into download mode (as discussed at the 34 minute mark of the following video: https://www.youtube.com/watch?v=ULxfLKsuCSs&t=1894s) but you are way ahead of me.  Nice work!

— Mick on 18.01.2022 at 15:43 (UTC)


I am from Germany an i got a foulty relabelt XMD 2041 for my own. 

Its Relabelt as a Voltcraft VC-7055BT but it has the Original OWON PCB boards with the XDM 2041 Labeling in it. 

And i will make it run again. 
It has the Boot Problem with stuck on Prograss bar. 

But i dont know how the reflash the Chip. And i have big Problems to understand How to Use the Solutions that are Postet here. 

I Hope somone of You can helb me Out with an Manuel or with a Step by Step Instruction for me. But i am a total Noob with this Kind of Knowledge. 

I Hope somone of You can helb me out with my Problem. 

Best regards 


— Torsten on 26.01.2022 at 00:45 (UTC)

Anybody knows, the Voltcraft version has the same problem with noisy resistance measurement?
Best Regards, Laszlo

— Laszlo on 02.03.2022 at 21:34 (UTC)

> With the default crystal, dividers of 16384 and 32768 provide averaging times of 10 ms and 20 ms, which would eliminate mains noise.
I guess this meant to say 100 ms and 200 ms instead of 10 ms and 20 ms, otherwise math do not work for me.

Also does this issue affect anything else, like voltage, current? I guess low millivolt range could also be similarly affected?

— Giedrius on 18.04.2022 at 05:02 (UTC)

@Giedrius You are correct, I have fixed the times in the article now!

I can see the effect in voltage measurement range when the probes are not connected to anything. But even a weak source with 10 kilo-ohm resistance seems to be enough to overpower the noise. So the only practical problem I've found has been with the resistive range.

— Petteri Aimonen on 18.04.2022 at 06:44 (UTC)

Thank you for answering. I'll consider buying this multimeter then.

— Giedrius on 24.04.2022 at 08:58 (UTC)