Messages

1

Brains Development / Connecting External Toggle switches?

« on: November 15, 2010, 03:57:43 AM »

Hi All,

I am sure there is a simple solution to this problem but after trying all sorts of brains and OEMs my own brain is starting to wear out.

I am putting a small control panel on my machine and have fitted a couple of toggle switches for the Feedhold and Single Step functions, this is so I can have hard wired LEDs in the buttons to show when they are active.  The trouble comes when I try to get this to work in Mach as these functions seem to only have toggle inputs. No matter what I try I can only get them to operate every second time round.

Does anyone know how each of these functions can be controlled by a single ON/OFF input?  Instead of Push On, Push Off?

Thanks in advance to anyone who can offer a solution!

Cheers

Pete

2

General Mach Discussion / Re: Dual function for MPG?

« on: July 05, 2010, 06:29:17 PM »

Sounds good to me, so now the big question is how do I write a brain?

3

General Mach Discussion / Re: Dual function for MPG?

« on: July 05, 2010, 05:51:58 PM »

I tried writing a small macro to do what you said and it does work, move the MPG, run the Macro and the FRO changes...Perfect!!  So far so good!  Saved it as a macropump and it sort of worked but as you say, very slow and erratic.  

So, now we have proven the principle, how can we implement it in a Brain?   I think the two main conditions  for this are:

1) Needs to work based on the condition of an input pin.
2) FRO should not be allowed to go below zero

In the macro I could only get it to work by storing the MPG count to use as the reference for the next cycle, since we need to determine the change in MPG DRO.  Can this be implemented in a brain?

The other way I could see it working is to trigger a Macro from another input pin, but how can you call a Macro from an input?

Cheers

4

General Mach Discussion / Re: Dual function for MPG?

« on: July 04, 2010, 10:25:22 PM »

Well, sort of familiar ....Can set up OEM codes to inputs and played a little with basic Macros, but unfortunately that is about it.  With this I can see your point, that is very clever, and it does sound quite easy in principle, but if we were to go with a macro then it would have to be triggered  (I don't know how a brain would handle it!). 

I do have one spare input pin, so if I couple that to an edge trigger on the MPG so as to pulse the spare input on each transition, that could call the macro to update the FRO.  I'll get on to it and see I can come up with.   

BTW, what is the best way to trigger a Macro from an input transition??

Cheers

5

General Mach Discussion / Re: Dual function for MPG?

« on: July 04, 2010, 06:22:23 PM »

I am using it through Greg's Smoothstepper board, coming in on Port3 as MPG1.  I have my own FPGA a little further downline from Gregs in which I can enable or disable the MPG signals depending on the mode (lock it out when in Auto).  This mode signal also comes back to Port 2 input pin to select MPG jog mode.

6

General Mach Discussion / Re: Dual function for MPG?

« on: July 04, 2010, 05:34:36 PM »

Thanks for your replies.   
Yes I am very keen to try it, but I have absolutely no experience with working with a BRAIN (not even sure I have one!) but willing to try anything once!  Thanks for your offer, and if you can I really would appreciate it.  I know time is a valuable commodity so if you can't find the time I am quite happy to do the work if you can give me a direction and some hints and pointers along the way.
Cheers.

7

General Mach Discussion / Dual function for MPG?

« on: July 02, 2010, 08:16:39 PM »

Hi All,

Does anyone know if the MPG can also be used as a Feedrate Override?  I am hoping to optimise on the inputs I have available on a new controller and want to implement a Feedrate Override knob.  Since I have an MPG wheel, and since this is used only for manual positioning, and not used when a program is running, it would be really cool if it's function could be switched from MPG jog to F/R Override.  Does anyone have any ideas on if or how this could be accomplished?