Messages

791

SmoothStepper USB / Re: When, Oh When, are we going to get backlash compensation?

« on: August 09, 2009, 11:23:09 AM »

Mach4 maybe wasn't even in the planning.

How do you know what Greg and Brian may have been discussing a year ago??

Folks never want to hear it but reducing backlash mechanically should always be the first step. Software can't fix everything...

792

General Mach Discussion / Re: Will switching motion system to Mach smooth out old steppers

« on: August 03, 2009, 09:20:24 AM »

'Roughness' can generally be attributed to the PC not putting out a nice clean pulse stream to the stepper drivers. Other processes running on the PC or sometimes the PC hardware itself can prevent the precise timing needed. I would first start with running Machs driver test and seeing that that looks like. On this forums download page you can also find a document that describes how to optimize the PC to run Mach, this can help out a lot in some cases.

The SmoothStepper works so well because it moves all the stuff that requires really precise timing onto dedicated hardware. I like to recommend them to folks as it eliminates the possible complications of the parallel port. The folks I have sold them too really like them.

793

General Mach Discussion / Re: Computer Load Vs Hardware.. Smooth stepper etc.

« on: July 31, 2009, 02:25:59 PM »

OK, that is basically what I am doing with the vector drive plug-in, I set the mode, direction and RPM. The rest of the interaction is done via handshaking with hardware lines (enable, etc.) You might be able to use it as a framework for what you are wanting to do.

794

General Mach Discussion / Re: Computer Load Vs Hardware.. Smooth stepper etc.

« on: July 31, 2009, 11:59:34 AM »

methinks this is one of those semantics things; multi-tasking vs multi-threading.

Sort of, multi-tasking works by dividing the processor time between multiple process/threads running on the machine. A process (task) can be made up of multiple threads. Even though all of these threads are running on a single processor the advantage is that they are running independently of one another. If one thread is waiting on disk access the thread redrawing the screen can still do its thing without waiting for the disk access to complete.

As to the question about talking to serial servo drive through Mach's VB script. You won't be able to do that, it is just too slow. If you want to try and talk to servo drives over a serial link then it needs to be done via a plug-in. When I get the vector drive plug-in done I'll post it as a reference.

795

General Mach Discussion / Re: Computer Load Vs Hardware.. Smooth stepper etc.

« on: July 30, 2009, 12:17:56 PM »

Remember computers have been multi tasking long before they had multiple processors. Separate threads do not need to run on separate processors, it just means they are running independently of one another, one does not have to finish before the other starts. In serial coms you tell it what to send and it goes off on its own and sends all those bits. You then get a callback if/when there is a response. The thread that asked for the communication to be sent does not stop and wait for a reply.

You can talk to a number of external devices over ethernet with Mach: G100, Galil, etc...

796

General Mach Discussion / Re: Computer Load Vs Hardware.. Smooth stepper etc.

« on: July 30, 2009, 10:49:05 AM »

Yes processes as show in task manager are not threads. Mod-bus, Ethernet, USB all are serial. Even the Vector drive plug-in I'm finishing does serial coms asynchronously (in its own thread) if you did not Mach would grind to a halt having to wait on serial coms to complete.

797

General Mach Discussion / Re: Computer Load Vs Hardware.. Smooth stepper etc.

« on: July 30, 2009, 09:24:30 AM »

 

Mach is not multi threaded

Oh yes it is! Among other things the toolpath display now runs in its own thread, any serial coms are also run in their own thread...

798

General Mach Discussion / Re: Computer Load Vs Hardware.. Smooth stepper etc.

« on: July 29, 2009, 11:36:42 PM »

Mach's parallel port drive is amazing. It is limited by the underlying PC hardware. No software generated pulse stream (on PC hardware) will be as accurate/smooth/jitter free as that from dedicated hardware. I've had decent luck with the parallel port but it can be a struggle on some PCs to get it working right and on some it will not work at all.

Using a PC for all the things it is good for (crunching numbers, nice display, etc) and a HW based pulse generator gets you the best of both worlds. It also completely eliminates the parallel port issue that many new users struggle with. I am a big fan of the SmoothStepper and reccomend them. Everyone I have sold them to have been really pleased.

799

Galil / Re: Strange #AUTO Galil program behavior

« on: July 27, 2009, 11:25:33 AM »

Well, the guys at Galil were stumped too. I did an Master Reset and even re-flashed the FW (and MR afterwords) and neither helps. It just seems to randomly stop parsing user programs. Guess it is time to send it in for repair. 

800

General Mach Discussion / Re: Struggling connecting Mach3 to a controller

« on: July 25, 2009, 09:17:40 AM »

What are the specs of the computers you have tried? Did you do a fresh install of Windows on the computers and run through the Mach optimization steps? Then run the driver test as mentioned above.

I like to recommend the SmoothStepper to folks: http://soigeneris.com/Warp9.aspx, it takes care of all the timing critical pulse generation for Mach freeing up PC resources.