Some time ago I bought a used small format Dell desktop (Optiplex GX280) that I was going to put Mach3 to drive the pp . As things turned out, ie it is not a good idea to run the pp in the house and it is too much trouble to move the desktop to the garage every time I want to cut something and my lovely wife has adopted the new computer with the phlatpanel LCD, I had to go back at figuring how to use the Dell C840 laptop for Mach3. In my initial tests I thought the motors were missing steps to an unacceptable level, like the axis were binding too much. Then I found out about the issues with operating system control and timing and gave up on the laptop idea and went for the inexpensive small desktop route.
As explained in the beginning the desktop is not practical, partly because it is not dedicated to cutting and partly because I want to stay married.
So I kept digging into the laptop thing. I tried everything I could find on the internet and finally I have something that works. The answer was found in the Mach3 FAQ forums and it says:

The secret is .... disable the ACPI driver!
Open the device manager and find the 'Computer' icon.
Click on the plus next to that and you will see something like Advanced Configuration and Power Interface (ACPI) computer. Chose the 'update driver' option and select 'Standard PC' as a replacement.
Windows demands a reboot after this, and a lot of the hardware had to be 'rediscovered' and reinstalled (all used drivers it knew about already, so was painless), another reboot for good measure and now it works flawlessly.

http://www.machsupport.com/forum/index.php/topic,5981.0.html

If you are going to use this method make sure it is on a laptop that will be used just for cutting, because it does get "neutered". After the lobotomy the laptop will forget about printer drivers, networks drivers, etc. It will never go to sleep again and the screen will not go blank unless you manually turn it off. But those side effects are a small price to pay if you have a laptop to spare for your precious pp . The little Mach3 test program will produce a near phlat line, a good indication that you have a clear uninterrupted pulse going thru the printer port. I was able to jog the axis without any missed steps at the IPM I was using with the desktop.

I will post an update when I actually cut something with the laptop driving the pp .

Stelio

 

I tried it, and it made no difference whatsoever. My parallel port still sucked! Maybe I did something wrong though, because the laptop never asked for a reboot, nor did any other drivers need to be refreshed. Maybe Win XP confused the issue.
I'm still hoping my SmoothStepper will fix everything.

btw, you should select "Standard P C" for your printer driver - The forum replaced those 2 letters (with no space) with the word "pc", but "Standard pc" is NOT a printer driver.

 

Correction made for the PC. Thank you for pointing out the error.
Stelio

 

After cutting the Eiffel tower and 66tbird's Gorilla I can say that the mod for the laptop works. Now I need to find another computer for unimportant things like my Quicken and TurboTax.

Did I mention how great the pp is for making stocking stuffers...

Thank you Mark and Trish!!!!!

Stelio

 

Oooooo! I am so jealous! :geek: