I should probably provide a link to the gadget I'm talking about--
All I have to control the desktop cnc mill I'm putting together is my macbook. I have windows on it, but no parallel port. I would very much love to be able to use my laptop for this purpose, but it seems that there is no easy way to do this. I have an idea for a workaround, though: sparkfun puts out a product called a usb bitwhacker that is recognized by the computer as a COM port, which can have individual pins set high or low. They make mention of its potential use as a parallel port replacement. I was thinking I could define the port address as the bitwhacker's port address in Mach or KCam, and it would work out.
Do these programs allow specification of port location like this? Is this feasible? Does anyone see a glaring reason why this would be domed to failure?
Thanks for your help!
This former thread may help
http://www.cnczone.com/forums/showthread.php?t=43895 (USB and Mach 3)
I'm an EMC2 user, but the same principles may apply.
1. USB to parallel port conversion does not work because the precise step timing information is not preserved. Alternativelly, motion controllers (such as smoothstepper) are available which are designed to work with USB.
2. Laptops are usually frowned upon for CNC machine control because the power management features may interrupt the control
I have used a Macbook Pro running XP via. boot camp to control a CNC machine, using a Smooth Stepper. It worked fine for me, though your mileage may vary.
I wouldn't consider relying on windows running under Parallels or VMware Fusion though - that's just asking for trouble in my opinion. Also, you wouldn't want to be doing anything else with the macbook at the same time.