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Title: Problem with delay DIR-STEP [Print This Page]

Author: Nikolay81 Time: 2018-8-7 00:39
Title: Problem with delay DIR-STEP
Last edited by Nikolay81 In 2018-8-7 00:44 Editor

A very big problem was discovered.
At first I could not understand what was happening, but the oscilloscope helped me in this.
For example, a person bought on Aliexpress, DDCSV and drivers LEADSHINE 556 (the most popular).
He wants his machine to work quieter, and sets the division step 1/32.
Configures the controller, sets the "X axis pulse equivalency" to 1280 (with the step of the ball screw 5mm).
Rejoices, for a while, how well and quiet everything works.
But the joy does not last long. Since, soon he notes that the machine loses its steps when changing direction.
Even at the lowest speeds.
He begins to read the instructions to the drivers, and finds out that the minimum delay between DIR and STEP should be 5 microseconds.
After reading the forums, he finds out that everything is even worse. For these drivers, it is desirable to exhibit a minimum of 10 microseconds.
It sets the "Time interval between DIR & pulse" parameter, for example, at 7000 nanoseconds (7 microseconds).
And then this bug happens.
At large values of "X axis pulse equivalency" (more than 1000) and simultaneously, greater values of "Time interval between DIR and pulse"
(more than 5000), the machine can not develop speed, more than 2500 mm / min.
What happens at this time with STEP signals is visible in the figures.
If you increase the speed, for example to 5000 mm / min, even the numbers on the screen will stop spinning.
That is, the controller just stops generating STEP signals.
If you reduce the "Time interval between DIR & pulse", for example up to 300, the machine quietly develops 10000mm / min.
And STEP signals have an ideal shape.
If you reduce the division of the step to 1/8, the problem also disappears. Since it appears, only at a high frequency of the STEP signal.

How to fix it?

Good STEP.jpg (47.33 KB, Down times: 1462)

Bad STEP.jpg (52.75 KB, Down times: 1426)

Author: ytliu Time: 2018-8-7 06:21
If there are losing steps when changing direction,you do not need to adjust parameter #416, you only need to change the definition of the pulse level of the relevant axis (#418-#421).

Parameter #416 is recommended to set 300ns.

脉冲方向说明.png (10.06 KB, Down times: 1006)

Author: ytliu Time: 2018-8-7 06:27
In addition, you can also change the pulse trigger definition of the drive to solve such problems.

Author: Nikolay81 Time: 2018-8-7 14:11
Perhaps we do not understand each other well.
I will try to explain.
For Leadshine drivers, and for many other drivers, the DIR signal must switch slightly earlier than the STEP signal.
I tried both STEP signal levels. Anyway, at a value of # 416 = 300ns, it loses its steps on the Leadshine 556 drivers when
change of direction. Because, the minimum delay between DIR and STEP should be at least 5000ns.
Only then, the steps are guaranteed not lost when changing direction.
It is a fact. See the screenshot of the instructions for DM556.
Also, here is a link to Purelogic's research.
http://wiki.purelogic.ru/index.p ... %B8_DIR_%D0%B2_PLCM
See the end of the article.
They found out that when STEP signal level is changed to low, the delay should be even greater. Up to 25000ns (!). Since the Leadshine drivers do not work correctly with low level STEP signals.
Can I not correctly understand the meaning of the "Time interval between DIR & pulse" setting?
In my opinion, it determines how much the DIR signal is generated before the STEP signal. This is necessary because the driver does not have time
in time to understand that the direction of movement has changed (see figure).
I am wrong?
In any case, the machine loses its steps at # 416 = 300 ns (with a change of direction). And at # 416 = 7000ns does not lose.
I tried STEP both high and low. It does not change anything. The problem is solved only by setting parameter # 416, more than 5000ns.
But there is a bug that I described.

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556.jpg (108.6 KB, Down times: 1384)

Author: ytliu Time: 2018-8-7 18:25

Nikolay81 Posted at 2018-8-7 14:11
Perhaps we do not understand each other well.
I will try to explain.
For Leadshine drivers, and for ...

For this problem, I need your cooperation.

Let's first look at the CW / CCW mode, will there be a loss of steps?

Parameters #230-#233(command type) and #234-#237(DIR in CW/CCW mode) have been added to the configuration file. You can set the command type to CW/CCW mode, and set the direction of movement of axis via #234-#237.

If the controller is in CW/CCW mode, configure the drive to the same mode.

install.zip

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Author: Nikolay81 Time: 2018-8-7 19:33

ytliu Posted at 2018-8-7 18:25
For this problem, I need your cooperation.

Let's first look at the CW / CCW mode, will there be a ...

Thank you.
I am very glad that you are ready to solve this situation.
For dealers, customers' appeals for losing steps are the biggest "headache".
At a distance, it is impossible to understand what happened - the screw is wedged, the drivers are not properly configured, the wires have a problem, or the controller is buggy.
And all cases of loss of steps, through the fault of the controller, should be known and have a solution.
The problem is not as simple as it seems.
The fact is that on programs like:
G91
G1 X + 10 F2000
G1 X-10
G1 X + 10
G1 X-10
G1 X + 10
G1 X-10
and so on,
steps are not lost.
For any values of the parameters # 416 and # 418- # 421.
And on complex programs (example in the screenshot) - are lost for any values of # 418- # 421.
But an increase of # 416 to 7000 helps.

Today I'll take the oscilloscope, and I'll try to understand what there really is a delay, between DIR and STEP.
I need a little time, maybe a couple of days. I want to accurately identify the problem.

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StepsLost.rar

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Author: ytliu Time: 2018-8-7 20:38
Last edited by ytliu In 2018-8-7 20:43 Editor

Nikolay81 Posted at 2018-8-7 19:33
Thank you.
I am very glad that you are ready to solve this situation.
For dealers, customers' appe ...

I carefully read the LEADSHINE-556 user manual. The problem should be caused by the current-limiting resistor R. The series resistance(R) of the pulse/direction signal of the DDCSV controller is 100 ohms,which will cause insufficient drive current,Especially at high frequencies, the front end optocoupler of the driver may not be turned on normally.

You can replace the R107 and R112 resistors with 0 ohms.

DM556.png (156.95 KB, Down times: 1371)

DDCSV.png (1.32 MB, Down times: 1357)

Author: Nikolay81 Time: 2018-8-7 21:45

ytliu Posted at 2018-8-7 20:38
I carefully read the LEADSHINE-556 user manual. The problem should be caused by the current-limitin ...

It is interesting.
I can see a part of the DDCSV schematic diagram with outputs STEP / DIR?

Author: ytliu Time: 2018-8-7 22:12

Nikolay81 Posted at 2018-8-7 21:45
It is interesting.
I can see a part of the DDCSV schematic diagram with outputs STEP / DIR?

If the R107 and R112 in the controller are not convenient to replace, you can replace the 270 ohm resistor in the drive with 150 ohms.

In addition, in the latest controller, R107 and R112 have become 22 ohms.

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Author: Nikolay81 Time: 2018-8-8 01:37

ytliu Posted at 2018-8-7 22:12
If the R107 and R112 in the controller are not convenient to replace, you can replace the 270 ohm ...

The CW / CCW mode unfortunately does not work properly.
In this mode, depending on the direction of travel, the pulses must be generated at the STEP or DIR output.
Instead, when this mode is enabled, pulses are generated simultaneously at the STEP and DIR outputs.
Of course, the axis twitches and does not want to move.
Settings # 234- # 237 do not change anything.
What am I doing wrong?

Author: ytliu Time: 2018-8-8 06:08
Last edited by ytliu In 2018-8-8 06:33 Editor

Nikolay81 Posted at 2018-8-8 01:37
The CW / CCW mode unfortunately does not work properly.
In this mode, depending on the direction o ...

Sorry, I made a mistake. Parameter #230-#233 If configured as 1, the output mode is A/B phase mode, the controller does not support CW/CCW output mode.

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Author: Nikolay81 Time: 2018-8-8 15:16
Does the controller not support CW / CCW for hardware reasons?
Or will it be possible to add CW / CCW support in a programmatic way over time?

Author: ytliu Time: 2018-8-8 17:10

Nikolay81 Posted at 2018-8-8 15:16
Does the controller not support CW / CCW for hardware reasons?
Or will it be possible to add CW / CC ...

Yes, the controller cannot support CW/CCW due to hardware.

Author: Nikolay81 Time: 2018-8-9 04:08

ytliu Posted at 2018-8-8 17:10
Yes, the controller cannot support CW/CCW due to hardware.

I understood why steps are lost and how to fix it. Please read the article in the attached file. Also there is the original article in the Russian language. Maybe it will be interesting to someone.
I could not attach the file to the message, and put it on Google Drive
https://drive.google.com/open?id ... zTQGxHBonuvyN_-mcTn

Author: ytliu Time: 2018-8-9 06:15
Have you replaced the resistor? The problem now is that the optocoupler does not work properly during high frequency operation due to excessive series resistance.

Author: ytliu Time: 2018-8-9 06:48

ytliu Posted at 2018-8-9 06:15
Have you replaced the resistor? The problem now is that the optocoupler does not work properly durin ...

Ia=(5V-0.7V)/(270+100)=11.6ma < 16ma

When operating at high frequencies, the logic signal current cannot meet the requirements, resulting in lost steps.

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DM556.png (156.95 KB, Down times: 1171)

Author: Nikolay81 Time: 2018-8-9 14:37
Last edited by Nikolay81 In 2018-8-9 14:42 Editor

ytliu Posted at 2018-8-9 06:48
Ia=(5V-0.7V)/(270+100)=11.6ma < 16ma

When operating at high frequencies, the logic signal current ...

Thank you. I also read the instructions to these drivers and consulted with familiar electronics engineers.
I will certainly remove the resistors today. Just for the experiment.
This takes time. In this situation, the dismantling of the controller is rather complicated.
The result "before" and "after", I will describe in detail.
But, even with the help of logic and mathematics, one can understand that this can improve the problem but not solve it.
Because increasing the delay DIR-STEP solves the problem completely. Without removing the resistors.In this, I was convinced yesterday on my experience.
In the Purelogic controllers, there were no resistors at the outputs, but they still skipped the steps with the Leadshine drivers.
While they did not increase the delay of DIR-STEP. Then the problem immediately decided.
Still, the question arises: why did they even add the "Time interval between DIR & pulse" setting, if its value can not be changed?
After all, if there is something, it should work. If it obviously does not work, it should be removed, so as not to embarrass the users.

Perhaps I do not understand something. Please tell me how difficult it is to fix the bug with the setting "Time interval between DIR & pulse"?
If it takes a very long time, or is impossible at all - I'll understand.
Then we will look for "ways to bypass" the problem.

Author: ytliu Time: 2018-8-9 23:20

Nikolay81 Posted at 2018-8-9 14:37
Thank you. I also read the instructions to these drivers and consulted with familiar electronics en ...

I have encountered many customers who have lost steps due to the "Time interval between DIR & pulse". By changing the pulse level, this problem can be solved very well.

As for the problem you are currently experiencing, you must first replace the resistor, and subsequent analysis is meaningful. After replacing the resistor, if there is still a problem, I will purchase LEADSHINE 556 and verify it myself.

Since this update involves hardware logic, I have to be very cautious, please understand.

Author: Nikolay81 Time: 2018-8-10 05:49

ytliu Posted at 2018-8-9 23:20
I have encountered many customers who have lost steps due to the "Time interval between DIR & puls ...

I replaced the resistors with jumpers.
I had resistors 100 ohms.
The driver input circuit diagram is incorrect.
Everything is completely different there.
Perhaps this scheme is version 1.0. And I have version 2.2.

Before and after removing the resistors, I shot the oscillograms, between the different terminals of the optocoupler with a logic output of 6N137.
This is a very common optocoupler. Datasheet on it, you can easily find it in Google.

Conclusion - nothing has changed. Perhaps there was a little more interference. In general, the signal at the output of the optocoupler has a lot of noise.
Unfortunately, the theory of improving the performance of the optocoupler, after shunting the resistor, was not correct. You can not remove the resistor.

I uploaded a waveform to Google Drive. They can be opened by the program "Multi VirAnalyzer".
You can download it here: http://english.instrustar.com/upload/image//English%20Version(3_10_7_1).zip

In some oscillograms, I was wrong with the division of the probe (put X10). There, the voltage should be divided by 10.
I think everything will be clear.

In some oscillograms, a different frequency.
This has been the case before. Often on the same programs, there is a different frequency. I do not know why this happens.

I will write more in detail tomorrow. It's very late now.

Here is a link to oscillograms:
https://drive.google.com/open?id ... dpnRbFb1pjd4J3THV3r

Author: ytliu Time: 2018-8-10 07:22
Last edited by ytliu In 2018-8-10 09:22 Editor

The current motor drive signal generation logic is: in each signal processing period (t), the DIR signal is first established, and the PLU signal rises at time #416 and falls at t/2.(see Attachment)

I will make the following changes:
The current signal processing period DIR signal does not change, the PLU signal rises at time 0, and falls at t/2;
Otherwise, proceed as before.

Since the motion of the system is planned, the speed at which the direction changes is generally low. At this time, t is relatively large, so the case of #416>t/2 does not occur.

This should be a relatively simple way to solve this problem.

I have already ordered LEADSHINE 556 and I will verify it.

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Author: Nikolay81 Time: 2018-8-10 14:38

ytliu Posted at 2018-8-10 07:22
The current motor drive signal generation logic is: in each signal processing period (t), the DIR si ...

Please cancel the order DM556.
Do not waste your money. You can not buy the same driver as mine.
If you can not cancel the order, I'll pay you. Just tell me how much it cost.
The problem is not only in DM556. Leadshine produces a huge number of driver models.
In addition, now most of their products are counterfeits (say 70%).
It is necessary, that the controller correctly worked with any drivers, and not only with 556.

In addition to removing the resistors and removing the oscillograms, yesterday I went to a company that has been repairing CNC machines for many years.
I asked their specialists to consult me for money, but they did it for free, for which I am very grateful.

They read our correspondence with you and explained the problem. We were both mistaken.
Everything is simple enough. Briefly, it is necessary to increase the delay "DIR-STEP" to 7000-10000 nanoseconds.
Then any drivers will work correctly with DDCSV.
You can partially bypass the problem, individually in the case of each specific driver.
But, only the correct delay DIR-STEP will make it so that there will be no problem at all.
With any drivers.

If you can not do this programmatically, you can hardware shift the signal STEP relative to DIR.
The simplest option is to install a circuit from the resistor and the capacitor between the driver and the controller.
It's a little bit ugly in the form of the signal, but as I saw yesterday, the optocoupler, it's still very ugly.

Today I will write an article in which I will describe in detail what they explained to me.

Please do nothing until you read the article. You also need to understand what is going on to solve the problem.

Author: Nikolay81 Time: 2018-8-11 01:14
Last edited by Nikolay81 In 2018-8-13 03:41 Editor

ytliu Posted at 2018-8-10 07:22
The current motor drive signal generation logic is: in each signal processing period (t), the DIR si ...

I wrote a new article for you.
I hope it will help you better understand the reasons for missing the steps and find a good solution.
This problem is quite difficult to understand. Perhaps machine translation will distort the meaning of some phrases.
But I'd better do it until I can.
Please read the article and tell us your opinion about it.

https://drive.google.com/open?id ... 9uvzhUmf3IJdtMNvpR_

Author: ytliu Time: 2018-8-11 06:24

Nikolay81 Posted at 2018-8-11 01:14
I wrote a new article for you.
I hope it will help you better understand the reasons for missing t ...

Thank you very much for your analysis of this issue, I will use the first way you said to make changes.

Author: Nikolay81 Time: 2018-8-11 14:47
Last edited by Nikolay81 In 2018-8-11 15:03 Editor

ytliu Posted at 2018-8-11 06:24
Thank you very much for your analysis of this issue, I will use the first way you said to make cha ...

Thank you, for your desire to solve the problem, dear Ytliu.
I understand that solving this problem is quite difficult for you.
Making changes to hardware logic can cause many other glitches.
I certainly do not ask you to solve the problem, right now.
In such cases, you can not hurry.
It is necessary to think everything over.
You can solve this problem in six months, or a year.

The main thing is that now DDCSV, a little "crippled" or "problem" controller.
Since it does not meet the specifications of the leading manufacturer of drivers.

And the solution to this problem will immediately bring DDCSV to a whole new level of quality and reliability.
It will be possible to raise the price for it.
For example, now I would not risk, sell a lot of DDCSV, like your dealer.
Because, by reason of technical problems with the product, this business can "eat" me later.
To earn good money, i need to sell at least 40 controllers a month.
This is 500 controllers a year.
If even 10% of buyers have a hard-to-solve problem with the loss of steps, I will spare all my free time, I will spend on technical support of users.
But life is too short to waste it so stupidly :-)
I ask you to understand my position.
Have a nice weekend.

Author: Mehmet Time: 2018-8-12 00:28
Dear ytliu and nikolay
First of all. Thank you for a lot efforts for find a good solution about a problem. Everyday I am following your posts.
I am learning a lot of things from your posts (systems, stepper drive, signal ,step-dır, step lose etc...)

I am a simple DDCNC 2.1 user , but i don't have a cnc. I need a lot of parts like stepper driver, screws, spinle ..For now, I have a DDCNC 2.1 controller.
I want to make cloosed loop cnc so , next week order a Lichuan closed stepper driver. If you are use closed loop step (with encoder) never losing step ?  Is it correct ?
I am not sure but Lichuan stepper driver's Logic input current : 10 mA at 60vDC @200kHz  Ia=(5V-0.7V)/(270+100)=11.6ma > 10mA. (formula from ytliu). is it ok. for controller dncnc?

I need your experiences, If i use this closed loop  driver , machine doesn't lose steps when fast changing direction. I it correct or not?
Should I use a pulley belt system for solve  torque , microstepping , step loses.

http://servo.xlichuan.com/prod_v ... 166&FId=t3:69:3

Soory for my english.I hose so you understand..

LCDA86H.pdf

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Author: alexwalex Time: 2018-8-12 02:08
Last edited by alexwalex In 2018-8-13 00:40 Editor

Mehmet, i use this drivers and he does not lose steps. I tested parameter #416=50 with 1920 pulse/mm and no have a problem. Maybe dear ytliu have more information.

Author: Nikolay81 Time: 2018-8-12 07:51

Mehmet Posted at 2018-8-12 00:28
Dear ytliu and nikolay
First of all. Thank you for a lot efforts for find a good solution about a pr ...

This is a good driver.
Use Falling-Low, # 416 = 2000, dividing step 1/16. And almost certainly, there will not be any loss of steps.
Although the manufacturer also indicates a minimum delay of DIR-STEP of 5 microseconds.
No additional resistors, do not put.
It is desirable to properly configure the antiresonance in the driver.

Author: Nikolay81 Time: 2018-8-14 18:06
While Ytliu tries (or does not try) to implement the delay of DIR-STEP programmatically, I'll try to do it in hardware.
Of course, this is not an ideal option. But if you do not get it programmatically, there will be a backup option.
DDCSV is a very good controller. I believe that he has great prospects.
It's a pity that due to this flaw, it can not work with many drivers.

There are already a few options for implementing a digital delay line.
I think, within a week, it will be possible to make preliminary samples.
In any case, I will achieve the solution of this problem, since these controllers are very interesting for me.

Author: ugv Time: 2018-8-14 19:15
why you don't install the old ver:2016-06-29-81NOR ? work well we can change the time beetween pulse and dir

Author: ugv Time: 2018-8-14 19:40
i can send you install files by mail if you want

Author: Nikolay81 Time: 2018-8-14 22:25

ugv Posted at 2018-8-14 19:40
i can send you install files by mail if you want

Thanks for the suggestion.
But in new versions there are a lot of useful changes that make work much easier.
In addition, it is not a question of changing the value of parameter 416.
It can be changed. But at a certain value of it, there is a breakdown of the STEP signal generation. Read the article.

Author: ugv Time: 2018-8-15 01:49
ok you think i wille be install this last firmware? where download?

Author: Nikolay81 Time: 2018-8-15 02:25
http://bbs.ddcnc.com/forum.php?m ... TA1OHw3OXw0Mw%3D%3D

Author: ugv Time: 2018-8-15 02:36
merciiii i will try it soon

Author: ytliu Time: 2018-8-15 06:25

Nikolay81 Posted at 2018-8-14 18:06
While Ytliu tries (or does not try) to implement the delay of DIR-STEP programmatically, I'll try to ...

Looking forward to your results. In addition, I have completed the logic design, the test results are satisfactory, #416 set to 7000ns can meet most of the drive requirements. Thank you again for your excellent work.

Author: Nikolay81 Time: 2018-8-15 15:24

ytliu Posted at 2018-8-15 06:25
Looking forward to your results. In addition, I have completed the logic design, the test results ...

Excuse me Ytliu.
I confess, I doubted your ability to solve the problem.
But your abilities, as always, exceed all expectations.

In any case, I will bring the digital delay line to practical implementation.
If you, for whatever reason, fail, the digital delay line will be a temporary solution to the problem.

Author: Mehmet Time: 2018-8-17 00:47
Dear nikolay / ytliu
Please, I need your helps.I will order Leadshine HBS86H cloosed loop step driver. Do you have any
experience for this driver? In the manual of driver, there are some technical notes. But, I don't want a problem like step lose. DDCSV 2.1 and HSB86H driver matching perfectly ?

-  power supply capacity? Which one is the good for the controller? In the table ;  60VDC 10mA  / 100VDC 16mA
-  In the manual, PUL/DIR notes: "Double pulse mode (CW/CCW) Software configuable" ? is it a problem for ddcsv 2.1? You are talking  a problem about CCW/CW.
-  R=0 if VCC=5 , I am not sure, Should I add resistor between controller-driver  or remove series resistor (101=100 ohm) form controller? or nothing.

I will be pleased if you help me
-

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HBS-90-8.2.PDF

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Author: Nikolay81 Time: 2018-8-17 04:45
Last edited by Nikolay81 In 2018-8-17 04:46 Editor

Mehmet Posted at 2018-8-17 00:47
Dear nikolay / ytliu
Please, I need your helps.I will order Leadshine HBS86H cloosed loop step drive ...

Your problem is that you think too much.
And you complicate the task too much.
You have an NC machine tool of an amateur class. Why do you need a stepper motor with an encoder?
Why such a powerful driver?
I do not know what country you are from. Maybe there you have all the millionaires and you just do not know where to spend money?
If I'm wrong and you are not a millionaire, buy cheap drivers, like DM556.
To him buy ordinary cheap stepper motors for 3 amperes.
Everything will work. I guarantee this.
Unless, of course, you do not sell defective parts :-)
If I'm not mistaken, and you're a millionaire, buy brushless servo motors.
They will be in all respects better than stepper motors with an encoder.

Author: Mehmet Time: 2018-8-17 06:28
All of machine parts are second hand ; stepper motors (nema 34 with encoder) , vfd , screws +nuts , etc. I am not millionaire

Author: Nikolay81 Time: 2018-8-17 14:37

Mehmet Posted at 2018-8-17 06:28
All of machine parts are second hand ; stepper motors (nema 34 with encoder) , vfd , screws +nuts , ...

Then take any Leadshine driver with the encoder.
Lichuan drivers are copies of Leadshine. Kind of like Adidas and Abibas :-)
You can take the driver without the encoder. The motor encoder is not necessary to connect.
Everything should work if the drivers are not defective.
Do not think about it that much.

Author: Biligo Time: 2018-8-19 04:37
Dear gurus, I would like to ask for your advice. Which drivers would you recommend purchasing? Which ones will work properly without any extra dance with tambourines. I have some sort of noname 4A drivers on the TB6600 chip (you can find lots of those on eBay for £5-6) but I still cannot make those drivers work without skipping steps. Does anyone have experience in working with DM542 drivers? Please share your knowledge.

Author: Nikolay81 Time: 2018-8-19 05:49

Biligo Posted at 2018-8-19 04:37
Dear gurus, I would like to ask for your advice. Which drivers would you recommend purchasing? Which ...

I would be in your place, I bought a normal digital drivers (your drivers are analog).
They now cost very cheaply for Aliexpress.
But if you want to "sex" with those drivers that you have, you first need to understand what part is to blame for skipping steps. Drivers, motors or mechanics.
It is necessary to disconnect the motors from the machine.
If the steps are still lost, it is advisable to get somewhere known to the serviceable motor, which does not exactly lose steps and check with it.
If this does not help, you need to understand the steps are lost when changing direction, or while moving in one direction.
To do this, you need to create special test programs.
When you give this information - I'll tell you what to do next.

Author: Biligo Time: 2018-8-19 09:14

Nikolay81 Posted at 2018-8-19 05:49
I would be in your place, I bought a normal digital drivers (your drivers are analog).
They now co ...

Thank you for your willingness to help Nikolay. I found a post on this forum, where Alessio uploaded pictures of that driver and said that he couldn't start it at all. Thereby, I really do not feel like having "sex" with them

I would like to hear people's recommendations on which drivers work the best with the controller DDCSV2.1

Author: Nikolay81 Time: 2018-8-19 17:41

Biligo Posted at 2018-8-19 09:14
Thank you for your willingness to help Nikolay. I found a post on this forum, where Alessio upload ...

I know people who have a machine running these drivers.
And it works well. But the controller there is not DDCSV.
By the way, I was mistaken. These drivers are digital. But they do not have a connector for tuning through a computer.
But if there is a great desire, you can get everything to work.
You can try to conduct the last experiment, before they throw it away.
Step division 1/8. # 416 = 7000. There are two jumpers inside the driver, J1 and J3. J1 must be opened and J3 closed.
Parameters # 418- # 421 = LOW.
Disconnect the motors from the machine, put the disks on their shafts. The diameter of the disks is equal to the diameter of the motor housing. Disks can be made from anything.
For example, from plywood or plastic. On the disks and on the body you draw serifs. On them you will determine if the motor loses its steps.
Speed is not more than 5000 mm / min.
And you try to run test programs.
Based on the results, sign off.

Author: ytliu Time: 2018-8-20 09:13

Biligo Posted at 2018-8-19 04:37
Dear gurus, I would like to ask for your advice. Which drivers would you recommend purchasing? Which ...

The tb6600 driver can be used with confidence, and we have a lot of users using it. If lost steps occurs during processing, change the pulse level polarity in ddcsv.

Author: Nikolay81 Time: 2018-8-20 23:18

ytliu Posted at 2018-8-20 09:13
The tb6600 driver can be used with confidence, and we have a lot of users using it. If lost steps ...

He does not have original drivers (noName).
With such products, anything can happen.
So, first you need to try the "ideal" settings and exclude the wedging of the ball screw.
If this does not help, you need to buy new drivers.

Author: Nikolay81 Time: 2018-9-2 01:28

ytliu Posted at 2018-8-20 09:13
The tb6600 driver can be used with confidence, and we have a lot of users using it. If lost steps ...

Sorry for the wait, Ytliu.
I was sick for a while. And the task was not as simple as I thought.
To make an effective digital delay line, it was possible on the shift registers.
I managed to implement 2 versions of the device: on microcircuits MC14557 (need 4 pieces) and 74HC7731 or 74HCT7731 (1 piece is needed).
The delay value is controlled by switches. The device is very small, low-cost, consumes little power, does not heat up and is easily placed inside the DDCSV housing (instead of 100m output resistors).
I post the schematic for MC14557. Because 74HC7731 is a rare chip. I have not received it yet. The circuit on 74HC7731 will be later.
The device is tested in operation and with an oscilloscope. It does not spoil the quality of the output signal. Loss of steps there.

Please rate the scheme, Ytliu. I value your change as a professional. Maybe I did not take something into account?

DELAY_MC14557.pdf

56.97 KB, Down times: 1018

Author: ytliu Time: 2018-9-2 07:53
Thank you for your excellent work. I saw the schematic and I think it has no defects. This circuit should be very good at solving the problem of losing steps.
DDCSV has built-in FPGA, I added delay logic on FPGA, it has been tested for a while, and it works well so far.

Author: Nikolay81 Time: 2018-9-2 17:26

ytliu Posted at 2018-9-2 07:53
Thank you for your excellent work. I saw the schematic and I think it has no defects. This circuit s ...

And how can "ordinary people" benefit from the results of your work?
Will it be possible, through the usual firmware, or Cyclone III, to be flashed separately?

Author: ytliu Time: 2018-9-4 06:23

Nikolay81 Posted at 2018-9-2 17:26
And how can "ordinary people" benefit from the results of your work?
Will it be possible, through ...

Your idea is correct, users can't update fpga themselves.

Author: Nikolay81 Time: 2018-9-4 14:47

ytliu Posted at 2018-9-4 06:23
Your idea is correct, users can't update fpga themselves.

Excuse my incomprehensibility. I correctly understood that now all DDCSV will be produced with a new firmware FPGA? And in them, parameter # 416 can be set to any number up to 10000 ns?

Author: ytliu Time: 2018-9-4 21:44

Nikolay81 Posted at 2018-9-4 14:47
Excuse my incomprehensibility. I correctly understood that now all DDCSV will be produced with a n ...

Users cannot update the fpga firmware themselves.
After the detailed test is completed, we will upgrade the fpga firmware in the new production ddcsv system.
In the new fpga firmware,parameter #416 can be set to any number up to 1ms.

Author: Nikolay81 Time: 2018-9-5 03:21

ytliu Posted at 2018-9-4 21:44
Users cannot update the fpga firmware themselves.
After the detailed test is completed, we will up ...

Thank you very much for your work, Ytliu.
I think the problem can be considered solved.
I hope soon all DDCSV will be sold with a new firmware Cyclone III.

Those who have already bought DDCSV and can not solve the problem of skipping steps when changing directions with settings, you need to collect a simple digital delay line scheme.
This solves the problem in all cases.

Author: Lukasz Time: 2018-9-8 16:10
Hello Ytliu,

Is it possible to program the FPGA by using external tool (eg. USB blaster) and JTAG connector on the controller PCB?
Are you able to provide firmware and instruction how to do that?

Regards
Lukasz

Author: ytliu Time: 2018-9-8 23:01

Lukasz Posted at 2018-9-8 16:10
Hello Ytliu,

Is it possible to program the FPGA by using external tool (eg. USB blaster) and JTAG c ...

Sorry, we are unable to provide firmware for fpga.

Author: bgarroweer Time: 2018-9-26 16:08
Last edited by bgarroweer In 2018-9-26 16:11 Editor

After the detailed test is completed, we will upgrade the fpga firmware in the new production ddcsv system.

To ytliu:
Did I understand right that the problem cannot be solved by downloading Upgrading Code from here https://www.nvcnc.net/ddcsv2.1.html and I sould buy new unit or add a piece of electronic circuit to it?

Author: ytliu Time: 2018-9-27 06:56

bgarroweer Posted at 2018-9-26 16:08
To ytliu:
Did I understand right that the problem cannot be solved by downloading Upgrading Code fro ...

Hi bgarroweer!

Your understanding is correct. However, in most cases, the problem of out-of-step is solved by adjusting the parameters.

In addition, we will soon release a new version of the DDCSV system, this issue will be fixed.

Author: bgarroweer Time: 2018-9-27 16:53
Thank you for answer, I hope new release will be soon, should I rely on this year? Because I want to buy particularly this controller (DDCS) with as less bugs as possible.

Author: Nikolay81 Time: 2018-10-1 18:02
I post, very simple and cheap scheme of the digital signal delay line. This is a very good and reliable option, but the main chip is difficult to buy. She was removed from production.

schematic.pdf

27.25 KB, Down times: 1092

Author: milawka2222 Time: 2019-1-8 16:36
Tell me, is this DM500 remote already free of this disease?

Author: ytliu Time: 2019-1-10 17:40
yes

Author: milawka2222 Time: 2019-1-13 03:32

ytliu Posted at 2019-1-10 17:40
yes

Thank you, I will take DM500

Author: Aleksandr Time: 2020-8-4 02:24

Nikolay81 Posted at 2018-9-4 14:47
Excuse my incomprehensibility. I correctly understood that now all DDCSV will be produced with a n ...

Николай,доброговремени суто!Прочитал,как чайник в электронике,с опозданием на 2года,Вашу переписку с разработчиками DDCSV3.1.Читал,как детектив,хотя больше увлекаюсь технической литературой.Вы сами не знаете,какие Вы молодцы,так бы еще совместно и прочие проблемы решать!Низкий поклон Вам за Ваше неровнодушие и Вашу любознательность.А с дровами ТВ6600,я тоже имел проблемы и долго не мог их решить.Построил чпу на 4еоси и походу токарный настольный станок.Всю жизнь бреди этой идеей,да только на пенсии дохожу потихоньку.В новой версии предел задержки повышен до9999н/с имногочего нового добавилось. Еще раз Спасибо Вам!Александр - Николай, доброговремен суто! Читайте как чайник по электронике, с опозданием на 2 года вашу переписку с разработчиками DDCSV3.1. Читайте, как детектив, хотя я больше увлекаюсь технической литературой. Вы не знаете, что вы молодцы, так что еще общего и решать другие проблемы! Низкий вам поклон за ваше безразличие и вашу любознательность. А с дровами TB6600 у меня тоже были проблемы и долго не мог их решить. Построили чпу на 4eosi и походу токарный настольный станок. Всю жизнь идёт эта идея и только на пенсию дохожу медленно. В новой версии предел задержки повышен до9999н / с добавлен новый счет. Еще раз спасибо! Александр

Author: Sabritezniti Time: 2023-2-14 20:31
I have problem with limit axis and spindle don't work please help

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