[MacRuby-devel] CNC Machine control using USB to IEEE 1284 Parallel port adapter

[Bill Hill]

On 18 Jan 2012, at 15:33, Will Thorne wrote:

> Hello,
> 
> Long time lurker making first post here. You could use an Arduino and do the real time pulse generation stuff on that. Then just write a macruby app that serialises the commands and feeds them to the Arduino which interprets them and flips the necessary IO pins on and off. It's years since I looked at this stuff but I seem to remember that CNC commands work such that they could be grouped into a single machining operation. Hypothetical example to cut a slot on a horizontal miller: Start milling cutter, start carriage +z, stop carriage, start carriage +x, stop carriage, start carriage -z, stop carriage, stop cutter. You could load that whole sequence into the Arduino if you break it down into groups like this. Put the arduino in a plastic box with a parallel port on one end and usb cable coming out the other? I don't know for sure that this would work, but in my experience microcontrollers are much simpler to do real time stuff on because they have pretty much no software stack compared to a desktop PC.

Hi,
Another lurker making a first post here! I'm getting into CNC Arduino and I've been doing very much what you describe. I've currently got a lathe/mill (Sieg C1 lathe + X1 head) that I've got driven by three steppers (Vexta PK545) with their driver modules directly hooked to an Arduino. I initially custom programmed the Arduino for each job, but now I'm sending simple commands from OSX and the Arduino parses the commands and bit bashes to step the motors. There's one step connection and one direction connection per motor, and one common "engage" connection to let me manually position; 7 outputs total. At the moment I'm manually sending CNC commands using screen, plus I've got a few custom routines as command line C binaries (drill a big hole with a small end mill and do a crib board ;-) I hadn't thought of using MacRuby for this...
Bill