Possible documented protocol options for a Mach3 controller

[MechanoMan]

I've kinda wanted to get into developing a motion controller since the printer port has been "problematic".  I do have significant microcontroller experience.

Now I asked about ModBus but from what I was told, it directly tries to write pulses so it's subject to the same problems if there's any glitches in the smoothness of the databus as the parallel port is.  My drivers suck anyways and being the tech guy I am would probably try to build drivers too, even if it costs more than buying them.

Ideally I'd expect to see some sort of format with either a more compact description of the operation- such as "513 pulses on this driver with this direction at this freq" and/or timestamps, and some sort of flow control so the sent commands will neither overrun nor underrun the controller's receiver.

I could always just modem over the G-code.  But there's a LOT of commands in G-code that might come up, and this basically removes Mach3 and all its useful functionality from the picture.  No, I still want Mach3 here, just talking to a controller through a completely reliable link.

I looked at some of the Mach3 plugins but I didn't see where they were actually documented so you could actually build a controller using it.  Are they intended to be proprietary, or did I just not look hard enough for documentation?

Are there good documented, open protocols that Mach3 uses that we can use to reliably talk to the controller?

[ger21]

Not sure, but I think this is what you're looking for.

http://www.machsupport.com/forum/index.php/topic,4884.0.html

[jemmyell]

Hi, that tutorial will get you started with the mechanics of plugin development.  There is also a wiki that has much good information.  Searching the yahoo group and looking thriough the files section is also useful.  Here is a blow-by-blow description written by Art Fenerty that tells how the Gecko G100 motion controller interface works.

http://www.machsupport.com/MachCustomizeWiki/index.php?title=The_G100/GREX_plugin_as_a_model_for_device_control

-James Leonard

[smurph]

Also, take a look at the Galil plug-in in the SDK.  You can download the SDK from the Mach downloads page.  There, you will see how Mach uses the Galil motion commands.  Then you can go to Galils website and download the user manual for a DMC-2100 controller and see what these commands are actually doing. 

You don't need much of a motion controller.  The Galil is far overkill for what is being fed to it.  Galil drivers will communicate with external Galil Ethernet controllers via TCP.  On an unmolested network, this is plenty fast and very smooth.  For a machine control interface over Ethernet, you would most likely use a crossover cable between the mach machine and the motion controller device.  Or a switch/hub in an isolated network. 

I would imagine that if you had a modbus motion controller that spoke modbus over TCP, then that would work as well.  You would just nee to write the modbus communication routines into your plug-in, or link with some library.

Steve

[vmax549]

A note here(;-) THe emc guys use the MESA I520 controller as a simple motion controller that is completely programable in two senarios. One is direct from mach the other as a self contained controller. Might want to check it out. All it needs is a plugin to MACH.

(;-) TP

[piv]

A plugin for the Mesa5i20 would be a good thing.

[ger21]

There's a post here from someone who was to be working on some plugins for those.

[piv]

Thanks, ive searched the forum for
mesa
5i20
and all I get is this post.  If you can link me that would be great.

[ger21]

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