Need Help!- USB v/s Parallel

[o1roadkingrider]

Hello all,

I'm looking into stepper/driver board kits, and need to make a decision soon. I'm purchasing an X2 from Harbor freight and want a NEMA 23 stepper set up. From what I'm finding most are set up for parallel ports. My HP laptop runs Vista and has no parallel port. I did find adapter cables on the net for linking a USB into Parallel port printers. Has anyone tried this? Would I be better off to use my ancient PC for my controler? I'm planning on using Mach3. Thanks!

JJ

[ger21]

Originally Posted by o1roadkingrider I did find adapter cables on the net for linking a USB into Parallel port printers. Has anyone tried this?

Won't work. You have a few options.

Use your old PC if it's 1 Ghz or faster, although it might work if it's a little slower.

Use a SmoothStepper, which emulates two parallel ports through a USB connection. www.warp9td.com

Use a ncPod. www.oemtech.com

Both the SmoothStepper and ncPod have Mach3 plugins available.

[sansbury]

I run EMC2 on an ancient (100MHz pentium something or other, 256MB ram) dumpster PC. I'm able to get plenty of speed and run it with the full GUI (Axis) without any trouble. If you're trying to save money you can probably get a machine like this out of your neighbor's garage or on Craigslist for next to nothing.

[cyclestart]

Originally Posted by sansbury I run EMC2 on an ancient (100MHz pentium something or other, 256MB ram) dumpster PC.

Wow, if it's Intel, possibly an original Pentium ? PII at best. Glad it works for you
According to the linuxcnc wiki some PII's have very adequate realtime performance.
Maybe it's a linux thing

What are the advantages to using a laptop for cnc? Other than the logic of "I already own it" ? Portability?

advantages of a cnc desktop
1) Usable units with good parallel port easy to find. Used is ok imho. Just think of it as "pre-tested"
2) Most of the parts can be placed in a safe location away from chips and flying tools. Under the bench works well. Get a rubber cover for the keyboard.
3) Parts are mostly cheap and easy to replace. Easier to build to your liking also.

advantages of a cnc laptop
1) Takes up less real estate.
2) Cnc programs can be created and simulation- tested away from the mill's location. This is easily worked around with the desktop alternative however.
3) Can't think of a third advantage atm.

If using Mach3 there may be another consideration. Some opinions* I've read on this forum suggest the computer with Mach3 should be kept as clean as possible. In other words a dedicated machine. What else do you need that laptop for ?

*This may or may not be a majority opinion.* I don't use Mach3, hearsay only etc.

EDIT/ Way OT but....
sansbury, according to wikipedia PII's start at 233 clockspeed. Are you sure the machine is 100MHz? I just installed Ubuntu 8.0.4 on a friends 400 MHz PII. It works but is noticably slower than my own 900 MHz PIII.

Further to the laptop topic. Using one for cnc may require changes to the bios that make it unpleasant for normal use.

[richlandrick]

I have run Mach 3 using two 800 mghz Dell boat anchor PCs for a couple of years with no problems.

According to Artsoft Mach can not be run on a laptop because of the power saving features built into laptops. It interupts teh data stream.

I do have a question for the well initiated out there. Ar ethere any problems using a USB to parallel cable when running Mach? My breakout board and of course mach are designed for parallel cables. My new duo-core computer doesn't have a parallel connection. Should I install a card to obtain a parallel output or will a USB to parallel cable do?

[HimyKabibble]

USB to parallel converters will absolutely *not* work with Mach3. You need a real PCI parallel port.

Regards,
Ray L.

[richlandrick]

Thanks Himy,

I did a little more reading after the post and came to the same conmclusion, but I'm very glad to get teh confirmation.

I decided on one fo these http://3btech.net/papopcicocaa.html

"Parallel Port PCI Controller Card - Add a DB25 IEEE1284 Printer Port to Your PC."

Thoughts?

[HimyKabibble]

That one should work just fine.

Regards,
Ray L.