Messages

7401

General Mach Discussion / Re: Does this product exist?

« on: September 22, 2016, 04:39:05 AM »

Hi Davek0974,
some good vid's on youtube about them. Reamarkably simple tho, three coils side by side
with the centre one energised by some AC voltage, few kHz is common, mine is 160kHz.
A magnetic core slips down the middle of the coils, if nearer one end than tother the outer coil
gets energised by transformer action, shift the core to the other end and that coil becomes energised.
Little bit of electronics and you have an infinite resolution linear gage with core in the centre
equal zero V.
They are available comercically as rugged contact free transducers. One with 1mm stroke but centre
accuracy of 100nm right through to 200mm and more stroke with centre accuracy of 20um.
I can't afford to buy one but I can make one! My current one offers 38mV/mm sensitivity and a linear
range of plus/minus 2mm. Not great but getting better.

Craig

7402

General Mach Discussion / Re: Does this product exist?

« on: September 22, 2016, 02:56:06 AM »

Hi Davek0974,
I've had a look at Tweaky's probe and its really nice, his workmanship is superb.
I've not seen anything like it for sale and can only guess that whomever bought
his design went no further with it, a shame.
Except for a few operator bungles I've never had a problem with probing. Nonetheless
I have considered no 'overrun' to be less than desirable.
A good microswitch is not a bad idea. Both Ormron and Honeywell make a competitive
line of switches with good repeatability, hysteresis and overrun. I achieve .01mm repeatability
with 2.5mm overrun with one such switch, I also use the same series of switches for home switches.

More recently I became a bit more ambitious and started making a linear voltage differential transformer.
Project not finished yet but testing shows .002mm absolute accuracy with +-2mm stroke. The example
I'm working on has an overall height of 110mm so not compact. Subsequent designs will be about 50mm
height 4mm stroke and 1um accuracy.

Given that probing works as well as it does this is probably a waste of time but I'm having fun!

Craig

7403

General Mach Discussion / Re: Help Please: Computer upgrade causes no communication with controller

« on: September 21, 2016, 02:11:39 AM »

Hi Preso,
I'm not familiar with your controller but your description suggests that it is governed by the parallel port.

It's not an ironclad test but running the Mach3 Driver Test program is simple and can often point you in the
right direction. Does it show a  'clean' or nearly so output. While I run my machine at a kernel speed of 25kHz
I sometimes test much higher, up to 100kHz just to get a feel for the PC's ability. Note that if you change kernel
speed you have to close then restart Mach to see the change, a mistake I've made.

Another useful test is to find the physical terminal on the controller board for the Estop and short it to 0V with a piece of
wire or a 100Ohm resistor if your concerned about letting the smoke out. It should signal Mach to Estop and if so
the controller can communicate with the PC. You could in theory test all inputs this way but becomes pretty tedious
often without learning much more.

If you have the original documentation for the controller find out if it needs an enable signal or possibly a charge
pump. A lot of non responsive BOB's are cured by getting the enable/charge pump settings correct.
Not sure why such a setting may have changed but subtle changes between one setup and another can be very
hard to spot.

One other possibility it the pullup/pulldown resistor settings. Not even sure that your controller has jumpers for
either but can be a source of much confusion when setting up. Given that you have tested the controller on the
old PC makes me think this is unlikely but sometimes changing something and thinking about the results will
inspire a 'lightbulb' moment.

Craig

7404

Mach4 General Discussion / Re: Return Codes

« on: September 18, 2016, 06:25:05 AM »

Hi DTG,
you're right, its totally pointless and your insight suggests not possible.

I imagined that an MDI call to a function that would navigate to a file and load it
would be pretty straightforward. The way you framed your question suggests that you consider
an MDI macro call to be in the nature of 'running Gcode' and such a function would fail as it
would be trying to overwrite itself.

The real purpose is to gain familiarity with Lua and wxLua. The example file dialog that I found in
the Lua Examples folder is really my focus. I need to manipulate it to navigate to a file, read line
by line, preform a mathematical correction and output line by line to a new file, suitably named.

I have done a similar thing in Mach3. My feeling is that the VB variant in Mach3 works but has holes
and Mach3 as good as it is has bugs. If I'm going to make the effort to learn a new language then
Lua is  more modern and capable, ergo the effort should be made there.

Craig

7405

Mach4 General Discussion / Re: how to connect analog joystick to Mach4?

« on: September 18, 2016, 03:57:57 AM »

Hi Leo,
I cant really help much but certain things are clear...

In order to use an analogue signal it will have to be converted to digital before Mach can use it.
On possibility is to use two ADC's (or one two channel) and communicate those values via Modbus.
The ADC's commonly used in microcontrollers are 12 and 14 bits and may therefore lack the resolution
you require. All in all this approach could be a major project.

I may be mistaken but I think HICON have an addon board which accepts two channels analogue. There may well
be others but I recall seeing that feature listed when I was surfing around.

Craig

7406

Mach4 General Discussion / Re: Return Codes

« on: September 18, 2016, 03:44:23 AM »

Hi,
now understand how errorcodes are passed around, thanks DTG.

I'm not out of the woods yet tho...

if(file:ShowModal() == wx.wxID_OK)then
            local path = file:GetPath()   
            local linecount
            local buf
            local rc
            local pathGenerating=1

       rc=mc.mcCntlLoadGcodeFile(inst, path)
            wx.wxMessageBox(tostring(rc))
            rc = mc.mcToolPathGenerate(inst)
           
           
            while(pathGenerating==1)do
                pathGenerating, rc = mc.mcToolPathGetGenerating(inst)
            end
            linecount, rc = mc.mcCntlGetGcodeLineCount(inst)
            buf, rc = mc.mcCntlGetGcodeFileName(inst)




            wx.wxMessageBox(buf.."    lines loaded  "..linecount)
                     
        end

The file dialog gets a good path and filename. If I debug it works ok.
If I run it as m150 at the MDI line it fails. The file dialog operates normally
but the file does not load or generate a toolpath neither the message boxes
come up to indicate progress.
One possibility I considered was that the instructions imediatley following the load
were happening so fast that it was 'breaking' the load.
You can see I've tried to put a while loop in there to allow the load/generate to
complete. It didn't work either, although that may be my poor coding than anything.

The other possibility that occurred to me is that when I start the macro the panel is
showing the MDI input and maybe the Gcode has got nowhere to go.

Might point out that this is not really necessary macro but rather an experiment
in Lua coding.

Craig

7407

Mach4 General Discussion / Re: Return Codes

« on: September 17, 2016, 02:48:37 PM »

Hi DTG,
thanks for that. I guess the definitions are in a C header file somewhere.

I have found, as you suggested I might, a file dialog example in the examples
folder which I can modify for my purpose.

Thanks again
Craig

7408

Mach4 General Discussion / Return Codes

« on: September 17, 2016, 06:52:00 AM »

Hi All,
yet another dumb question from a  Lua virgin...

Have written this code in a file dialog:

rc=mc.mcCntlLoadGcodeFile(inst, path)
            if(rc==MERROR_NOERROR)then wx.wxMessageBox("success")

When debugging the path variable is good, it correctly indentifies a Gcode file
but the return code is a number, value=0.

The API.chm reference:

rc = mc.mcCntlLoadGcodeFile(
      number mInst,
      stringFileToLoad)

and the return codes are:

MERROR_NOERROR No Error.
MERROR_INVALID_INSTANCE The mInst parameter was out of range.
MERROR_INVALID_ARG FileToLoad is NULL.
MERROR_FILE_EXCEPTION Exception while loading file.
MERROR_FILE_EMPTY No data a in file.
MERROR_FILE_SHARING Violation sharing file.
MERROR_FILE_INVALID Not a valid file type.
MERROR_FILE_BADSIZE Invalid file size (over 1.5GB).
MERROR_FILE_NOT_FOUND The file cannot be found in the file system.
MERROR_FILE_BADFORMAT The file had a line end without a new line character. The file may be incomplete.

How is it that the return code from my function call is numeric?

Is MERROR_NOERROR=0
and MERROR_INVALID_INSTANCE=1
and MERROR_INVALID_ARG=2

etc.

Craig

7409

Mach4 General Discussion / Re: Namespace?

« on: September 13, 2016, 03:18:55 AM »

Hi DTG,
looking at the range of mc.mcCalls 99% of any script I'm likely to want/need
are going to be these.
There is one feature that I would like to build into a script however is a 'file browse' window.
When you call 'load Gcode' for instance you can browse to your file of interest and
I presume the function returns a path/filename to the calling app.
I haven't yet found a script or program fragment which codes such a feature but when I
do I will study it mighty hard that I might replicate it for my own use.
Clearly such a feature would be coded with the wx.wxFuncs which in turn create and
manipulate graphics windows and access Windows file structures. Also seems likely to
be reasonably complicated so may have to take some patience pills!

Craig

7410

Mach4 General Discussion / Re: Namespace?

« on: September 13, 2016, 02:58:56 AM »

HI DTG,
thanks for your reply.
That example is great, exactly the style of thing that I'm looking for. Enuf
detail to get the basic structure and syntax and a clue as to how it works.
Then go to a reference manual to get the nitty gritty details.

Craig