I like to see the contraptor based on a broader (and open source) software base, like linux.
And your board seems to be a cheap alternative to all the arduino-electronics and drivers, which makes it more attractive for beginners.
I almost went down this path myself, but there was one big factor stopping me. The lack of parallel ports on modern computers. If you have a laptop, you can just forget about it. I didn't want to buy an entire computer to just act as the decoder. If you are working with small motors, have you thought about using the newer RepRap driver board? It is supposed to have less heat issues, and it can do micro stepping. It is also supposed to cost less. http://reprap.org/wiki/Stepper_Motor_Driver_2.3
Thank you Oliver. I guess all that software around Arduino even the python scripts and the firmware are open source too and can be run on each operating system. Thats there advantage over EMC. But EMC is able to work as a live-CD so that no installation is necessary.
It's right, that modern computers lack more and more a parallel port. At EMC there are some attempts to get it running with USB, but this seems to be a hard challenge, because USB doesn't support real time support.
I'm glad to have a parallel port on a fairly modern PC. And my next PC will have one also. For me the overwhelming advantages of EMC are more valuable than using the Arduino board (I like it very much) and the software around it. The existing software is sensed too restricted for me compared to EMC, I don't have the skills to improve it and I don't see a consistent, tactical development for this software.
So let's see it as two ways to use CNC-machines now, depending what you prefer for yourself.
During the forthcoming holidays I will add some pics, maybe videos and descriptions. All in all it's quite easy to get it run with EMC. Until that have a look at Configuring a L297 Board Reprap Stepper v1.2 on linuxcnc.org.
Today I got all the files finished to show you, how I got the Contraptor Mini-CNC running with the Enhanced Machine Controller - EMC.
First of all an understanding of the parallel port is very helpfully. Here is a picture of a 25 pin female D type parallel port connector
And here is a schematic picture of it:
I general
the blue pins are data output pins
the red pins are data input pins
and the green pins are grounded at 0 Volt.
Here is a table showing you how I connected the parallel port pins to the pins of the Reprap Stepper Motor Driver v1.2 (only the connected pins).
Parallel Pin
Function
Stepper Pin
2
XDIR
X-4
3
XSTEP
X-3
4
YDIR
Y-4
5
YSTEP
Y-3
6
ZDIR
Z-4
7
ZSTEP
Z-3
10
XMAX
X-7
11
XMIN
X-6
12
YMAX
Y-7
13
YMIN
Y-6
14
AMP-EN
X-5, Y-5, Z-5
15
ZMAX
Z-7
21
GND
X-2. Y-2, Z-2
The pins are mirrored because this is for a male connector.
The schematics I made with KiCad (I can't upload files here in the forum. I will inform You where to get the files.)
Here is a picture of the PCB. I used the Toner-Transfer-Method. Here is the PCB you can use for it. I will explain it more detailled when uploading the KiCad files.
And here is a video, which gives you an idea, how to run the Mini-CNC with EMC2.
Very helpful video; I'm wondering why it was not possible to run the GCode - it looks like the "exceeded dimensions" error is really a warning as it allows to proceed anyway?
