Hi everyone. I was eying CNC machines for a while (even bought a set of stepper motors and stuff once to build one). The stumbling block for finally going through with it was always that CNC programs only seemed to work with the parallel port. This had a number of problems for me and I guess I am not alone with at least some of those.
1) the parallel port is a dying breed
2) using the parallel port as GPIO is always troublesome (it was never designed for that purpose)
3) running true real time applications on ANY OS (including RTOS) is located somewhere between really difficult and impossible.
4) it would require me to have a full PC with keyboard and monitor etc. in the garage with the CNC machine and all the other dust and particle generating tools/machinery. Not to mention the space a PC would take up...
A little while ago I was looking for solutions again as I do about once a year or so. I figured perhaps a Linux solution may now run on the Pi. And sure enough someone has done the great deed and made it work. Thanks a LOT for the great work! Now all that would be needed is the official Pi touch screen (whenever that arrives...
Meanwhile I finally got a small CNC machine and just spent the day struggling with Mach3 on my PC to check out if the machine is working, only to end up tossing Mach3 to the can. The pulsing engine driver simply refuses to install correctly. So I wrote a quick hack Java program to generate pulses on the parallel port. At lest the machine responds on all three axes. My true hope is that this will be much less troublesome on the Pi. At least someone finally saw the light of day and moved the pulse generation off the host machine.
The next project will be making a copy of the PICnc-V2 parallel port adapter for the Pi. I will probably recreate a copycat of the existing design in DipTrace. One thing I am planning to change is to allow for a straight (40 pin) ribbon cable connection to the Pi2. There should also be a power connection on the board to optionally feed the Pi from a robust power supply through the ribbon cable, instead of a USB adapter. If there are any other ideas floating around for changes on that circuit please let me know. I will try to incorporate them as I go.