Now I get the circular interpolation part. Its not that it *cant* do it if the axis pitches aren't the same, it just means that it'll take CPU power to calculate the ever changing slope of the eliptical path required to cut that circle. As long as your computer is fast enough to do the calculations within the time span required to complete a command, you won't notice anything. If its not fast enough, the controller will have to twiddle its electrons for a bit, waiting for the new information to be calculated and sent.
Oh and yes, I was trying to make out what all the screw connectors were on the controller. I think the ones on the left side of the picture are home switch inputs, the rest I couldn't really make out.
I'd like to suggest that the desciption of the controller board could do with some expansion. Just looking at the description I didn't realize that it was really a complete breakout board with limits, estop, etc. To a noob it seemed more like a copy protection dongle (incorrect assumption of course). I've only just recently become aware of the difficulties with bit-banging the parallel port through windows. I Guess its one of those things that "everyone knows so why bother explaining?" things we all fall into.
At $100 it seemed like a horribly expensive copy protection dongle. Now that I know what it really is, $100 seems quite reasonable to me. Hell, I spent $60 putting together a urinal flush timer for work - and believe me it was NOT complex.
So far DeskCNC is the front runner for me. Mach2 looks damned good too and I like the price but, I want to do mostly 2.5D stuff (PCBs, front panels, etc) and DeskCNC seems to be the least hassle on my part. DeskPCB looked OK too but who knows, might want to move up to a "real" milling machine sometime and whack some metal around.  |