2.5MBIT, Isolated USB to RS232/RS485/TTL Out Converter

[devfirat]

When you design project with line connected you have to be careful about isolation. Otherwise you can say goodbye to your USB ports or even your computer!

If you use RS232 or RS485 communication you have to get one of isolated converter with USB input and yes they are not so cheap!

So i designed open hardware platform for this purpose so you can use it very easyly!

You can read about test in this article (It is Turkish).

http://www.firatdeveci.com/usb-to-rs232rs485ttl-cevirici-usb2rsx/

[Old_but_Alive]

just an initial look at the photo.
looks like a very nice layout

Jumpers J1-J5  I hope you didnt use conductive paint which destroys the isolation  

[Sideshow Bob]

Did you consider using the ADUM4160BRWZ in your project?

[devfirat]

@old_but_alive: Of course it isn't conductive paint It has 3kV isolation!

@sideshow bob: I thought to use it but ISO7242+RS232+RS485 chips combine are more cheaper than that.

[Gallymimu]

seems nice but:

BOM seems incomplete i.e. IC4 is missing as are some resistors.

If it's open source where are the released design files?  Or did you mean you only made it open for manufacturing?

In any case thanks for sharing.

[Sideshow Bob]

I thought to use it but ISO7242+RS232+RS485 chips combine are more cheaper than that.

I was actually thinking on the cheaper ADUM3160BRWZ version writing this. But anyway your totalt cost argument is completely legit in your design choice

[devfirat]

@Gallymimu: IC4 or others are not missing. I wrote "TAKILMAYACAK" means "BE NOT CONNECTED". Besides IC4 and IC5 are same. Sometimes we can use wide package for RS232 side. There are two packages on same area. You are right, it is open for manufacturing.

[Gallymimu]

@Gallymimu: IC4 or others are not missing. I wrote "TAKILMAYACAK" means "BE NOT CONNECTED". Besides IC4 and IC5 are same. Sometimes we can use wide package for RS232 side. There are two packages on same area. You are right, it is open for manufacturing.

Thanks for the clarification.  I wondered if it meant DNI (english version DO NOT INSTALL)

[Vineyards]

I have checked your site devfirat and it seems you are doing a lot of good work there. Thanks for sharing with us. It seems you are into converters and the stuff. I have one of these Chinese 4020 CNC's that come with a parallel port based controller. As parallel port has become obsolete, it is no longer supported in 64bit OS's (Windows based). Do you think a USB to Parallel Port converter that will not miss steps can be designed. As far as I know existing hardware can't keep up with the timing requirements...

[devfirat]

@Vineyards: Thanks for you comment. As you can see I am not a communication guy. I am power electronics engineer and these kind of stuffs were developed because I work all day with mains so it is very dangereous for me. So I need them and I do not trust to chinese products.

If I want USB to Parallel port converter one day, be sure i will share with everybody

[Sideshow Bob]

I have checked your site devfirat and it seems you are doing a lot of good work there. Thanks for sharing with us. It seems you are into converters and the stuff. I have one of these Chinese 4020 CNC's that come with a parallel port based controller. As parallel port has become obsolete, it is no longer supported in 64bit OS's (Windows based). Do you think a USB to Parallel Port converter that will not miss steps can be designed. As far as I know existing hardware can't keep up with the timing requirements...

Some mother boards still come with a parallel port header like this board ASUS P9D WS but others also. Using a PCIe card will most probably cause allocating of non-standard parallel port addresses to PCI parallel port cards. As the software may look for the port at standard parallel port addresses-0x0378, 0x0278, and 0x03BC. I am not sure how the USB to paralell converter solve this problem. Anyway if your board do have an paralell port windows 10 should support it i think. At least in the 32 bit version. As I have read on the net USB to paralell converter may be the best way to go. If your computer do not have any paralell port. All I can say is that a lot of cut-and-try may be needed. Do not buy anything if not the firm have an return policy

[Vineyards]

Mach3 supports 32 bit OS and it seems to run on 64bit ones. Perhaps a virtual parallel port software could aolve the problem.  I am not good at Windows API programming but if it works for serial ports it should work for the paralled one too.

[Sideshow Bob]

Mach3 supports 32 bit OS and it seems to run on 64bit ones. Perhaps a virtual parallel port software could aolve the problem.  I am not good at Windows API programming but if it works for serial ports it should work for the paralled one too.

It looks like mach3 support PCIe types paralell port addresses. As long as the driver is supported by your OS of course. I would then had gone for PCIe card supported by your OS. Se the manual http://www.machsupport.com/wp-content/uploads/2013/02/Mach3Mill_Install_Config.pdf page 61

[Vineyards]

I have about 5 parallel card some PCIe and some PCI but still no joy.

[Sideshow Bob]

I have about 5 parallel card some PCIe and some PCI but still no joy.

Have you tried installing a windows 10 in 32 bit version. It should be quite easy to make a dual boot setup with windows 10 in 32 and 64.

[mars01]

If you are searching for an USB controller that work with MACH3 out of the box and with a good price, you can use Pokeys boards. They are made and sold by some guy in Slovenia (w w w . p o s c o p e. c o m - remove the spaces for the correct address). It costs around 40 euro (USB version, without shipping costs)) and they have a MACH3 plugin. Just the board itself can work up to 25KHz step frequency but it can go higher (up to 125KHz) by adding a simple HC595 register.

I posted a project in this section with a board that I made to interface with Pokeys and has the above-mentioned HC595 on it, but right now, due of missing steps when stopping the spindle (big power spike), I am designing a new add-on board totally isolated (optical and also using isolated DC-DC converters).

Then you can use a notebook to control your CNC (nowadays laptops don't have parallel port anymore and no extension ports like PCMCIA or the like).

There are some other open source/hardware projects of CNC USB controllers based on GRBL project (like Smoothie project) but they do not work with MACH3.

[Vineyards]

I have no problems with 32 bit OS's. The problem begins when I try to use it on 64 bit system. You know many CAD packages run on 64bit. All I want is having everything on the same PC setup. At the moment, I try to desing using 64 bit system and use a 32 bit one to get the CNC working. I will check out on your tip and please let me know if you get that daughter board design working without losing steps.

I have also found something which might be interesting. My setup passes the benchmark performed by the drivetest utility provided by ArcSoft. However, when I test for lost steps by getting the head to return to the zero point, I observe discrepancies when the speed is higher than 25 or 35kHz.

[mars01]

Windows is not a real time OS (neither Linux but Linux at least tries hard to be) therefore there are some other tasks that it tries to execute while generating the pulses for stepping. Increasing the stepping frequency too high might get in conflict with internal mechanisms of the OS (a fight for processor time) and steps might be lost. This is why the best solution is an external step frequency generator especially if it is made with a FPGA...
Unfortunately the price for those FPGA based USB controllers might be a bit high so in between is where Pokeys type of devices find it's place.

Once I finish the design and I am happy with how it works, I will share the project here for all to use.

[Vineyards]

Have you tried installing a windows 10 in 32 bit version. It should be quite easy to make a dual boot setup with windows 10 in 32 and 64.

Yes I did. I have setup Windows on two different hard drives and boot selectively. However when you have to change something you still have to shut down and boot up, shut down again and boot up once more.