Problem with delay DIR-STEP

Nikolay81

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?

Sabritezniti

I have problem with limit axis  and spindle don't work please help

Aleksandr

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

milawka2222

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

Thank you, I will take DM500

ytliu

yes

milawka2222

Tell me, is this DM500 remote already free of this disease?

Nikolay81

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.

bgarroweer

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.

ytliu

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.

bgarroweer

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?