breakout board

[nitroboy]

Hi all !

I hope this is the right forum to ask this question.
So I made a CNC mill with an USB controller but I have some problems with it.
And I was thinking if it would be better to make a parallel port breakout board ?
Does anyone know where to find a scheme, I was searching for it but there are so many and I don't know what I have to look for.
Im using leadshine optoisolated drivers.

Thanks in advance

[nitroboy]

someone ?

[Al_The_Man]

What are you looking for exactly? If you already have opto's I would drive them from the P.P. output with ULN2002/3/4 style buffers, or you can drive a 24vdc load directly from the output of the ULN and do away with the opto's.
Al.

[nitroboy]

So if i understand this it would be enough to use uln200x to protect my computer ?

Do I need an external power supply ?

and then I can use mach 3 to run it ?

[Al_The_Man]

What are you trying to protect your computer from?
The PC power supply is at ground potential anyway.
I usually connect all power supplies commons to a Earth ground also.
It depends if you want to go the total isolation method, I suspect this causes more noise problems than any other.
Proper grounding is essential either way.
Either method you can use a separate supply for the external outputs, I use 24vdc.
Al.

[nitroboy]

Thanks for the reply but do you know where i can get a scheme of an breakout board.
I can't find one.

[Iron-Man]

Originally Posted by nitroboy Hi all ! I hope this is the right forum to ask this question. So I made a CNC mill with an USB controller but I have some problems with it. And I was thinking if it would be better to make a parallel port breakout board ? Does anyone know where to find a scheme, I was searching for it but there are so many and I don't know what I have to look for. Im using leadshine optoisolated drivers. Thanks in advance

Check here; http://www.cnczone.com/forums/genera...schematic.html .

See this link; DIY Parallel Port Breakout Board .

Hope this helps,

Iron-Man

[MrWild]

PMinMo.com has everything you need to make your own. Schematics, parts lists, and board art.

[nitroboy]

thanks allot

[nitroboy]

just one more quastion.

on this board http://members.shaw.ca/swstuff/bob-lg-brd.png
can I connect 6 limit switches instead of the pp11, pp12, pp13, pp16, pp01, pp14 ?

that would be great
thanks

[Iron-Man]

Are you using Mach3 or EMC2?
Those outputs use the same buffer.
Depending on the software that you are using you may have to make changes to the design. This BoB was set up to use EMC2, not Mach 3, even though I am using it with Mach 3 and EMC2, just for the X,Y,Z and A axes. In other words, your software needs to be able to map to the pins that you want to use for those 6 limit switches.

Hope this helps,

Iron-Man

[nitroboy]

Yes it does help, thanks