Recent Posts

1

Projects, Designs, and Technical Stuff / Control of 2 CAN Open DS402 motors on a single shaft

« Last post by Simon on Today at 06:55:40 pm »

Having mostly mastered CAN Open (well fix one problem and now your see the next problem more clearly  ) I have been looking at how to refine my motor control.

I have two motors that are couple to the load with some elasticity - literally. Lets just approximate the system as two motors that drive a common shaft via belts and the are mounted such that for the shaft to rotate the motors rotate in opposite directions.

So I immediately discarded the idea of using the motors in speed controlled mode. A short experiment proved my theory right, One motor will take over all of the load delivery while the other will be left lazy. I want them to share.

So I went with Torque control. I send a sync message to the network, get the speed of the motors back, average that speed and decide on how to change the torque, then I send the new torque setting. It works OK, I am still debating with myself as to whether I should update often with small values or less often with larger values. At his point I started looking around for information on how to consider setting up a DS402 motor driver to run in torque mode with my external controller (CAN Open master) doing the speed control.

I came across an example of a non CAN Open motor system for a conveyor belt where one motor is run in speed control mode with additional "helper" motors running in torque mode. EUREKA!

But that makes my wonderings about precise settings even more relevant as now the two motors will have different behaviors while achieving the same thing together. The idea is that I no longer need to send a sync message to get the speed from each motor, process that and issue new torque commands. Instead I would send the speed required to one motor and send the sync message. The speed controlled motor will respond with it's target torque as well as actual torque. The torque controlled motor will be set up to receive this target torque as it's torque demand and so setting both motors to the same torque. In this way there is no race between the two motors with one taking over but I get to use the much faster and certainly better designed speed control loop in the motor driver than my own machination that is just keeping up.

Obviously that the motors are mounted opposite ways round is a problem as whatever the torque of one motor is the other needs the negative of the number. I currently do this in my program before sending the numbers out to the two motors. There is a setting somewhere for the encoder that basically reverses it's interpretation, need to look more into this one to see if there is a way to overall reverse the motor direction.

What I do wonder about though is the tuning of the two motors works. I guess that as the helper motor is just that it's torque does not need to be identical but I also do not want to confuse the speed control loop in the speed controlled motor. I suspect that the torque controlled motor needs to react faster than the speed controlled one so that it adds or subtracts it's torque in time for when the speed controlled motor is expected to achieve it's speed and so not confuse the system.

Has anyone ever done this?

2

Beginners / Re: Convert US standard 115V to International 230V

« Last post by tooki on Today at 06:53:57 pm »

As a practical matter, most modern electronic equipment is designed to work equally well at 50 or 60 Hz.
The more likely problem is 100 vs 120 vs. 240 V.

It’s already established that the device runs on two universal-input SMPSs. Model numbers much earlier in the thread.

3

Beginners / Re: Convert US standard 115V to International 230V

« Last post by tooki on Today at 06:53:02 pm »

The transformer really doesn't care if it's 50 or 60 Hz, it'll run fine either way. If it's a
50Hz transformer it'll actually run slightly cooler at 60Hz because it may have more
copper in it. And a SMPS will generally also run OK at either line frequency.
Unless there's some kind of frequency sampler circuit that wants to see a particular
line frequency(which would be rather odd), it's not worth the bother to design the
device for one or the other.

There is no transformer, just two SMPS.

4

Test Equipment / Re: Choosing between entry-level 12-bit DSOs

« Last post by KungFuJosh on Today at 06:52:30 pm »

Exactly. That's why I did 1s persistence to illustrate the glitches better over the limited framerate of the web console.

5

Beginners / Re: Photodiode output emulation

« Last post by tggzzz on Today at 06:49:07 pm »

This depends very much on how accurate you want to model the PD behavior.
The simplest would be to use a function generator and a resistor.
This works if your PD is zero voltage biased and your circuit can work with either side of the PD being at Earth ground as that's where your function generator ground will usually be at.

It works when simulating reverse-biassed PIN diodes, provided the input of the transimpedance amplifier is at (virtual) ground level.

You are of course missing quite a few secondary effects of the PD, such as junction capacitance and non-linear behavior if voltage develops due to the TIA not maintaining the zero bias (during transients).
The latter also affects the accuracy of the current. To minimize the effect, you should set the output voltage of the function generator as high as possible and then adjust for the desired current by picking larger resistor values (ideal current sources have infinite source resistance and infinite compliance voltage).
That being said there are many PD configurations where what I described would not work, so we would need to see your schematics.

Yup.

The frequency and transient response fidelity are key requirements in the OP's use case.

6

Test Equipment / Re: Choosing between entry-level 12-bit DSOs

« Last post by BillyO on Today at 06:45:32 pm »

and the display persistence hides the deviation of the peaks from the real value.

Persistence will not hide the peaks, it will tend to broaden the trace to include both peaks and the troughs and everything in between over the period of persistence.  Maybe you are thinking of averaging?

7

Test Equipment / Re: Hacking the Rigol MSO5000 series oscilloscopes

« Last post by BTO on Today at 06:42:02 pm »

FYI - I've created a new post that is dedicated to putting the Dr Mefisto solution in one place .
So far i've only go the post up with the description

AT THIS LOCATION
https://www.eevblog.com/forum/testgear/hacking-the-rigol-mso5000-dr-mefisto-licensing-method/new/#new

I will make and attach a PDF (Not ready yet, I need some sleep)
I'm also in the process of creating and in depth tutorial Video to follow along step by step

I believe with everything in 1 place and simple video instructions and my availability to help people if need be, there is no reason why everyone shouldn't start jumping onto this ASAP.

Give me your thoughts.

8

Projects, Designs, and Technical Stuff / Re: Powering NeoPixels from 3.3V - Wrong but everyone does it?

« Last post by Siwastaja on Today at 06:41:09 pm »

Remember that most 3.3V rated microcontrollers (etc) are rated to max recommended operating voltage of 3.6V. Sometimes this is all you need to interface (or like in this case, share power) with some "weird" chips, without needing multiple supplies or level shifting.

If you do use 3.6V, you might want to carefully look at regulator tolerances and maybe pay a bit premium for a 1% part instead of the absolute cheapest 3% accuracy regulator, though.

9

Security / Re: Microsoft repackages apps with a telemetry .NET wrapper

« Last post by radiolistener on Today at 06:39:44 pm »

Not sure I want anyone to know any of that! It's just a matter of degree, isn't it? Where one draws the line. And don't forget we are on about those not asking permission but just gobbling the stuff, because.

This is really going much more deep. What will protect you from some criminal who decide to use online access to your electric car computer to make some "small mistake in the firmware code" which leads to failure of brake and gas pedal and take remote control over the steering... and you get into a traffic accident. And there is no way to check what happens, because computer will have some seconds to clean all tails and log events. That is the price to allow internet access for your car computer...

So what I mean is that a proper opt-in system makes it clear that the software isn’t, for example, uploading your document to them.

What will prevent to collect the data independently on that opt-in setting?
The same as it happens with MS?

10

Test Equipment / Hacking the Rigol MSO5000 - Dr Mefisto Licensing Method

« Last post by BTO on Today at 06:38:51 pm »

HACKING THE RIGOL MSO5000 - Dr Mefisto's Fully Automatic License Activator

BACKGROUND :
This post exists because of the main rigol MSO5000 Post and specifically because of the python scripting method reverse engineered by Dr Mefisto (This is the VERSION 2 of the script)
https://www.eevblog.com/forum/testgear/hacking-the-rigol-mso5000-series-oscilloscopes/2671/

Also because SMAS laid out their path to activation in a very easy to understand way.
https://www.eevblog.com/forum/testgear/hacking-the-rigol-mso5000-series-oscilloscopes/2840/

But also because a few members have stated that there should be one simple place to come to instead of having to dig though almost 60 pages of discussion and then it's a matter of finding the files.
The unavoidable fact of these posts is that they will be long and will have many pages.

THE PROBLEM SUMMARIZED :
- As always it starts with us wanting to unlock all the features of the MSO5000 (or whatever scope it is at the time)

- as the method progressed it was quickly realized that rigol (Unlike the DS2000A) were not using "Symmetrical Encryption" but instead "Asymmetrical Encryption" which meant that since
  we didn't have Rigol's encryption key, we were not able to approach the solution in the same way. At this stage the "PATCH METHOD" was put into place.
  And it worked, but it had 1 problem... It would not survive a firmware upgrade. So in the future when the next upgrade came out and you installed it you would lose all your unlocked options.
  Same thing if you downgraded. But don't get me wrong... If you stayed on the same version you were totally fine and everything worked.

- Then in Post #2671 Dr Mefisto had a eureka moment and worked out a python script that would CORRECTLY LICENSE THE SCOPE. (Actually the original script was in an earlier post and Post 2671
  is the version 2 / aka The Automated Script.

- However a lot of people found this challenging and difficult to perform. it became the case that faced with "Patch Method" vs "Python Licensing Method" it was seen much easier to do the former.

WE NOW HAVE A FULLY WORKING SOLUTION...

FIRST LET ME THROW SOME FEARS OUT OF THE WAY
It has become obvious also that even though everyone should upgrade to this method as it means.... when further upgrades come out you will have nothing to worry about and you'll just download
the official upgrade from the Rigol website (No further hack or patching required). But even though everyone SHOULD, They are not doing it.

Why not ?

- one reason may be you're afraid of change and what may happen, because if it's working now with the patch why change ?
Answer : Because you'll have to anyway

- You've heard rumours of the scope being bricked

- You've heard people having problems with it

- You've heard that the script can damage your scope

LET ME PUT ALL THAT TO REST

- My scope started on V 1.3.0.3  )00.01.03.00.03) , i used the patch method and went up to 1.3.3.0 (Latest Version). All Options Unlocked
  I then Downgraded to 1.3.2.2 (During the downgrade all options are lost). I then used Dr Mefisto's script to license the scope and All Options were unlocked successfully.
  I then upgraded to version 1.3.3.0 ALL OPTIONS SURVIVED,  I then downgraded just to push my luck , to 1.3.0.3 ALL OPTIONS SURVIVED,  i even went as low as 1.1.4.4  ALL OPTIONS SURVIVED.

So Upgrading and downgrading is not a problem , But there's a catch, You can't downgrade via the operating system you have to do it in the Pre Boot Menu

- A Note on the Pre Boot Menu.  There are 2 Options   "Firmware Upgrade", "Restore Defaults" .  FIRMWARE UPGRADE both upgrades and downgrades your scope in a Pre O/S Environment.
  However RESTORE DEFAULTS Just restores your defaults,
IT DOES NOT Lower you to a lower version of firmware
IT DOES NOT take your scope back to it's original version (After you upgraded)
All it does is.. if you changed the settings in your scope, it restores them to stock settings.  This step is NOT necessary in order to upgrading, Nor does it avoid you bricking your scope if you don't do it.
it is a good step to do, but let there be no illusion, it's not a necessary step.

- I have , at the time of writing this post upgraded and downgraded my scope over 30 times just to see if i could brick it and around 3 of those times i used restore defaults, the rest i didn't. Nothing happened.  I have gone between the patch and back to the script method over and over.  THIS METHOD IS A VERY RELIABLE METHOD

- A WORD ON BRICKING YOUR SCOPE
1. You're probably not going to
2. IF YOU LOSE POWER during the FRAM copy process YES.. YOU'LL BRICK YOUR SCOPE
3. IF YOUR LOSE ETHERNET CONNECTION during the FRAM copy process... YES, YOU'LL BRICK YOUR SCOPE
Because the data stream cannot be interrupted until it gets to 100%  (this only applies to the .. maybe 2mins that the FRAM is actually being written to)

If this method doesn't work for you you can always revert back to the Patch Method if you wish.

- I have observed that most of the problems arise either from fear or lack of knowledge how to do this method  so......

HERE IS WHAT YOU NEED TO DO
(This post has been put up so that if you can get through it you won't need to watch the video) but i have included a video that will take you through it step by step.
and you can also ask me for help and i'll be happy to help you


STEP 1.
DOWNLOAD THE FOLLOWING
Rufus
https://rufus.ie/en/

Python
https://www.python.org/downloads/

THEN. GO TO MY MEGA CLOUD SERVER
https://mega.nz/folder/A8cEgQRI#5FSoMrCurJi71T7VkRPgYQ

Here you will find a few things that you'll need

1. Scope Firmware Version 1.3.2.2
2. Scope Firmware Version 1.3.3.0
3. Rigol_kg2.py   (Dr Mefisto's Script Version 2)
4. THERE IS A PDF FILE TO COME with detailed instructions (when i finish it and give it a name this line will be edited)
Download all of those

OPTIONAL
- Downgrading to 1.3.2.2  Video (this video shows you how to get into the Pre Boot Menu)
- FULL TUTORIAL VIDEO (Name not established yet and video is still to come, I'll keep you updated)


THE ACTUAL UPGRADE PROCESS

I'm going to give you 3 options

OPTION 1 - I will BRIEFLY detail the steps in this post , You can take a crack at it if you feel competent, However i personally feel if you are competent enough you wouldn't be here in the first place.

OPTION 2 - There will be a DETAILED pdf of the steps at my MEGA cloud location , Download the pdf and follow that

OPTION 3 - You can download the full tutorial video and watch it step by step, it's not short, but it will explain everything.


NOW...
HERE ARE THE BRIEFLY OUTLINED STEPS that you'll have to do

(THESE STEPS ASSUME THAT YOU HAVE A DECENT DEGREE OF NETWORKING EXPERIENCE AND BASIC PROGRAMMING EXPERIENCE - Python is preferred but not necessary, But you MUST have had
some experience actually programming from scratch, not just uploading sketches into arduino for example. you must be familiar with C.L.I. if you don't know what C.L.I. is then don't do this method.
you must be familiar with flashing EEPROM Basics.)

Now, i'm not saying Dr Mefisto's method is hard, i'm just saying, if you want to take the quick road and just read this post and jump in the deep end, IT DOES REQUIRE TECHNICAL KNOWLEDGE.
The other option is the PDF walkthrough or the video. But the method is easy, it's just very particular.

so...
- Get a USB Stick (up to 16GB)
- Download Rufus and format the USB stick to FAT32 File System (or... You can just use windows format if you like, but SOMETIMES this causes problems) Rufus is more reliable.
- Establish which firmware version your scope is on.

-  To do this upgrade you will need to start on Version 1.3.2.2
   If your scope is on 1.3.3.0 or lower , You will need to download 1.3.3.0  and 1.3.2.2 
   If your scope is on 1.3.2.2 then you only need to download 1.3.3.0
so Download the upgrade / Downgrade files that pertain to your situation

(NOTE : I AM ASSUMING A WINDOWS 10 PRO ENVIRONMENT - If you have Linux of Mac Make the appropriate Adjustements , Although i will say a few things later regarding Linux that you need to be aware of.)

- if you are on 1.3.3.0 and patched , Put the 1.3.2.2 software version on your USB stick             (First use Step 1 and do your backups) , Then Use the STEP 2 GEL file and put it on your USB stick.
- if you are on 1.3.2.2 with no options installed (You're fine), You just need to download the 1.3.3.0 firmware, Use Step 1, Do your backups , Then use STEP 2 GEL file and put it on USB Stick

- Now you need to turn off your scope, Insert the USB stick into the scope, and Enter the PRE Boot menu and do the firmware ugprade
 (You can feel free to select RESTORE DEFAULTS if you want, it doesn't hurt anything )

- After that , Regardless of what version you started on, you will not be on Ver. 1.3.2.2

- Now download the rigol_kg2.py script
- Open your command shell  YOU HAVE THE CHOICE TO USE WINDOWS cmd.exe OR  WINDOWS POWERSHELL  (Powershell is recommended), it has had a higher success rate.
However, sometimes during the python install it will  favour Windows cmd over Powershell and most times it will just work on both. (Work it out). Start in Powershell though if not sure.

- now whatever directory your command prompt or Powershell is starting in, Copy your script to that location .

- NOW SET UP YOUR NETWORK
You need a router (Internet is not required) (But the downloaded files are)
You need a PC
The PC needs to be connected to a LAN Port in the back of your router
You need an MSO5000
the MSO5000 needs to be connected to a LAN Port in the back of your router
(This is a basic Star Toplogy Configuration)

MAKE SURE THE POWER IS RELIABLE
MAKE SURE THE ETHERNET CABLES ARE PLUGGED IN PROPERLY
Make sure you don't have a lightning storm going on or power outtages
Make sure you don't have shit power boards and that everything is securely plugged in and can't fall out (YOU'VE BEEN WARNED... IF YOU BRICK YOUR SCOPE IT'S BECAUSE YOU IGNORED THIS)

Now that everything is connected

- Download Python
_ Install Python (this is the part where ... if you're not sure... Read the PDF or watch the video)
If you install python and run it and you can't connect to the scope (Uninstall Python and do not proceed with this method, but instead do the PDF or Video method). i'm assuming here you know
how to install python correctly and run it and have basic programming experience.

- Now take that USB stck out of your scope

- Obtain the scopes IP Address and Use Command prompt or powershell to run a ping command to see if your PC is communicating with it.
IF YES... Proceed
IF NO... Troubleshoot the network
Stay on AUTO and DHCP (Try to avoid using STATIC IP)

- TYPE    Python  Into the command shell or powershell to see if it connects to the python interpreter
if it does
- TYPE  exit()  and press enter   (do not enter the commands directly from the python interpreter) Use cmd or Powershell only to interface with the interpreter

Now you want to see what options you have before you   (ASSUME MY RIGOL SCOPE IP ADDRESS IS 10.1.1.666) 
TYPE
python rigol_kg2.py -h 10.1.1.666
Press ENTER
this will bring up the help menu (you can do no harm to your scope by doing this)
The options we are interested in  the SWITCHES that we are interested in are
-h HELP   --------------------------------- (THIS CANNOT HARM YOUR SCOPE)
-i INFORMATION ------------------------ (THIS CANNOT HARM YOUR SCOPE)
-r REGENERATE PRIVATE KEY--------- (THIS GENERATE THE PRIVATE KEY (Priv Prem) needed before activation)
-u UNINSTALL THE OPTIONS--------- (THIS Uninstalls all options and bundles) so if you are on 1.3.2.2 with installed patched options, you use this option to uninstall them

NOW LET'S PULL UP THE SCOPE INFORMATION
TYPE
python rigol_kg2.py -i 10.1.1.666
Press ENTER
Note the version of the scope
Note if the options are FOREVER or -
if you are on 1.3.2.2 and it says FOREVER because you used the patched version  do this now

TYPE
python rigol_kg2.py -u 10.1.1.666
Press ENTER
Make sure to restart your scope after this

If you now have
- All Options Uninstalled
- and are on 1.3.2.2

WE ARE NOW READY TO GENERATE THE PRIVATE KEY.... 
(Ensure you do not lose network or power connection at this stage)

TYPE
python rigol_kg2.py -r 10.1.1.666
Press ENTER
EXPECT THIS...

- the information table will appear
- A progress bar will appear that says "READING CFRAM"  ... Let it get to 100%
- Then "APPLYING NEW CFRAM"  Let it get to 100%
(if it seems to stall for longer than 1 min, it means you clicked on the screen,   RIGHT CLICK to un pause, then leave it alone)

- Then you will see multiple lines of ACTIVATING
- at the end of it you'll get an information window.   The options will still NOT BE ACTIVATED (that's normal)

NOW WE RUN THE SCRIPT
TYPE
python rigol_kg2.py 10.1.1.666
Press ENTER

After this you will expect all options to be activated (They won't be), That's also normal

- Now REINSTALL 1.3.2.2    even though the current version is 1.3.2.2  DO IT AGAIN,  put the USB in the scope with that firmware version on it and run Firmware upgrade again.
(Sounds stupid.. Just do it)

- Then follow the steps again
Get the python INFORMATION up again
NO NEED TO REGENERATE THE KEY THIS TIME
Then just run the script again
TYPE
python rigol_kg2.py 10.1.1.666
Press ENTER

THIS TIME YOU WILL BE ACTIVATED

BUT WAIT , YOU'RE NOT DONE JUST YET

- Now erase the USB stick and load 1.3.3.0 onto it

- do the Pre Boot Menu UPGRADE FIRMWARE to 1.3.3.0

NOW YOU WILL NOTICE A FEW THINGS

1. You're now on 1.3.3.0
2. ALL YOUR OPTIONS HAVE SURVIVED A FIRMWARE UPGRADE
3. You're not good to go

REMEMBER THOUGH

1. Do a self check (3 tests)
2. Do a self calibration
3. RUN YOUR BACKUPS AGAIN (Always remember to backup)

NOW YOU'RE ALL DONE , that's it