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Author Topic: Minimum PC requirements vs real life (Newbie)  (Read 15192 times)

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Re: Minimum PC requirements vs real life (Newbie)
« Reply #10 on: June 21, 2015, 12:19:04 PM »
When you say the PC doesn't need to be close to the table, you do realize that CNC involves a LOT of personal interaction between the operator, the PC and the machine.  This is like sitting in your office and sending a report to the networked printer down the hall.  The operator has to fixture parts, pick up the origin, install and/or change tools, check clearances at holding points, sometimes halt the program and move the holding devices, on an on.
Re: Minimum PC requirements vs real life (Newbie)
« Reply #11 on: June 22, 2015, 08:45:43 AM »
Thanks Gary, I'm not planning on putting the PC in a different room, I'm just looking for a little more freedom on setup. I'm not sure where the table is going to go yet, and am hoping to keep the cable off the floor.
Re: Minimum PC requirements vs real life (Newbie)
« Reply #12 on: June 22, 2015, 09:33:27 AM »
Thanks Craig, I don't mind spending a little more of my client's money if it means better performance and less downtime, which I generally get from a mid-range workstation vs a desktop for an extra $100 or so (plus $150 for the GPU in this case). My client wins in employee satisfaction/productivity and lower IT consulting costs. My users won't mind tinkering with the software or the router, but as far as the PC goes, they just want it to work and stay out of the way, so although they're similar to the members of this group, they're not as tech savvy which needs to be accommodated.

Re: Minimum PC requirements vs real life (Newbie)
« Reply #13 on: July 03, 2015, 04:10:59 AM »
Hi  ITGuy,
how did you get on? Did you find a combination to suit the customer?
Can't help but think you can spend as much as you like on a computer but the slightest hitch with competing software/graphics/LAN/anti virus
and you end up with a stall at best and a CRASH at worst. A crash can be very expensive, thousands... and if an operator happens to be in the firing
line injury is assured.
I suffered a crash in exactly that manner, namely a 3d redraw was sufficient to starve Mach3 and an axis stalled, on resumption it crashed and bloody near
taking my hand as well. My limit switches were poorly configured and response was to slow anyway. Since then I have made it a rule that NO other
software be installed let alone running while my machine is energised. LAN, firewall, antivirus nill/nada/zip, I mean nothing that may even remotely
interfere and have never had a problem since.

Craig
My wife left with my best friend...
     and I miss him!
Re: Minimum PC requirements vs real life (Newbie)
« Reply #14 on: July 03, 2015, 11:14:14 AM »
Thanks Craig, I'm still waiting for them to find some space on the shop floor and choose an external controller. I'll definitely minimize the software on the box but hadn't considered an AV scan bringing it to a screaming halt! I might dedicate some cores to the production apps to avoid unwanted interference. Are you sure your problem was a resource issue and not a corrupt buffer or something like that?

Bruce

Offline BR549

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Re: Minimum PC requirements vs real life (Newbie)
« Reply #15 on: July 03, 2015, 12:08:02 PM »
Just a note. ANY function outside of MACH3 CAN(but not always) interfere with Mach3 being able to maintain sync with the pulse ouput. It all depends on how loaded the CPU is when the outside event occurs. ANY program that is running either in the foreground OR background can cause this problem. Eventually even a low cpu load can be effected. It all just DEPENDS.

That is why it is recommend to ONLY run MAch3 and NO background or monitoring programs when controlling a machine.

Just a thought, (;-) TP
Re: Minimum PC requirements vs real life (Newbie)
« Reply #16 on: July 03, 2015, 12:45:03 PM »
OK, so what I'm hearing is that Mach 3 doesn't need much as far as resources go, but if it doesn't get what it needs, it fails horribly. Dedicating a CPU core or two to Mach 3 should get around any CPU bottleneck issue, and I assume it's ok at allocating enough RAM for itself; any other runtime events I should be considering?

Bruce
Re: Minimum PC requirements vs real life (Newbie)
« Reply #17 on: July 09, 2015, 04:10:05 AM »
Hi Bruce,
you are obviously way more knowledgeable than I about dedicating cores and similar and that may prove to be an excellent solution.
My experience is not so much that the CPU gets overloaded but rather it gets a stream of high priority interrupts with certain processes
or apps. What reading I have done suggests interrupts are an important mechanism that Windows uses to communicate between threads.
Further those interrupts are assigned a priority by Windows with little or no control by the user.
Competing interrupts screw with the pulse stream generated by the Mach pulse engine. Admittedly I still use a PP and of course have made myself
vunerable to this problem. From what I have heard in the forum is that an external controller relieves the CPU of demanding interrupt timing and
much improves Machs ability to run smoothly.
Are you of the opinion that a dedicated core is less suspect to competing interrupts than a multiple cores running the same thread?

There are some questions I have about external controllers as well. I understand that Mach becomes a trajectory planner and sends via a buffer
by USB or Ethernet to the controller. What I want to know is wether the contents of the buffer have to be flushed thru to the controller before
the controller can signal back to Mach some external event like a limit switch or probe switch event. If that is the case then the latency of USB
could be significant if you were expecting a critically timed event signal. It may be for that reason that Ethernet controllers seem to enjoy a better
rep than USB amongst our most experienced users.

Craig
My wife left with my best friend...
     and I miss him!
Re: Minimum PC requirements vs real life (Newbie)
« Reply #18 on: July 09, 2015, 08:50:36 PM »
Dedicating a CPU to Mach 3 probably won't be of any benefit. I have set Mach3 at highest priority in the past and it makes little if any difference. The main issue with Mach3 is the memory use. If you can force it to run in memory AND use the best memory you can get without pageing out you will find it works fine. Watch for Video Memory buffers and such as well. I have an i5 System with 4GB memory in Vista running antivirus, networking(WiFi), Video and at times Various programs for calculating different engineering work. This does not cause problems, However!!!! do not run anything while you are cutting, watch for timeouts on system components. As you would be aware in the BIOS or now days the UEFI there are time out periods in there that need to be overridden. Also watch for little things like "allow the system to switch of this device" settings within the actual configuration in PP,USB,Video,etc etc. these will destroy parts. I think the biggest thing to worry about with using Mach3 is making sure your setup is bulletproof to start with.


Wes
Let us know how you Go

Offline ger21

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Re: Minimum PC requirements vs real life (Newbie)
« Reply #19 on: July 09, 2015, 08:59:47 PM »
Quote
If you can force it to run in memory AND use the best memory you can get without pageing

It also works fine on my 1Ghz Pentium III with 256MB of RAM, even with very large files (500,000 lines). Personally, I think you can throw your memory theory out the window.

Basically, if you're using the parallel port, then you just need a PC that Mach3's parallel port driver gets along with.
With a motion controller, it should run on just about anything.

The only issue that occasionally comes up is with onboard video or very low spec video cards. And I mean very  low spec.
Gerry

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