Messages

421

Mach3 under Vista / Re: 2% jog (.001) Metric on Axis A & B not accurate

« on: December 05, 2022, 10:49:46 PM »

Hi,
I suspect that your steppers have microstepping regime of 8 microsteps per full step or more.
When you click the MPG Mach will issue say one or two steps but the steppers will not move until four, five or six steps have accumulated.
This is a common problem with steppers, you might think that if you have 1600 steps per rev if Mach issues one step it will move 1/1600 of a rev,
but not so. This is because the differential torque between micro steps diminishes very rapidly beyond half stepping.

The practical maximum resolution of a two phase stepper is 400 steps/rev (or half stepping) irrespective of the microstepping regime.

Craig

422

Mach4 General Discussion / Re: force screen label to refresh

« on: December 05, 2022, 10:27:24 PM »

Hi,
sometimes the screen does not update or updates infrequently or sporadically. This is because the  Lua GUI chunk, ie the screen runs
as a co-routine with Machs core. Only one can run at a time, and there are occasions where Machs core hogs all the processing time
and the screen misses out.

Co-routines are Lua's only way to have mulithreaded applications but co-routines are co-operative, one thread cannot force the other
thread to yield.

Craig

423

Mach4 General Discussion / Re: PLC Inputs

« on: December 04, 2022, 06:04:10 PM »

Hi,
the signal script fires ANYTIME the signal changes state, and so it will trigger on activation, but also on deactivation.

I would guess that your BoB/motion controller has active pull-ups, and therefore the signal script will trigger on the negative going transition
not the more normal positive going transition.

Craig

424

Mach4 General Discussion / Re: Doing math to DRO values

« on: December 02, 2022, 05:10:51 PM »

Hi,

but please remember they are write and read as strings, not numbers.

That is not correct. Try experimenting.

There are three APIs to set the value of a register:

mcRegSetValue()      stores a numeric value, I suspect a 32bit floating point IEEE 754
mcRegSetValueLong()      stores an integer value, I suspect 32 bit signed
mcRegSetValueString()      which as the name suggests stores a variable length string.

As an example I tried this piece of code:

Code: [Select]

local regHandle=mc.mcRegGetHandle(inst,"iRegs0/MyString")
local string=mc.mcRegGetValueString(regHandle)
local string=string/2.07
where I stored '6789' as the value of the string. One some occasions the division failed, dividing a string by a numeric value does not really make sense, but on
other occasions the string was re-cast and the division proceeds with a real result, ie a fractional portion. I have yet to discover why Lua sometimes re-casts and sometimes
not.

Another example:

Code: [Select]

local regHandle=mc.mcRegGetHandle(inst,"iRegs0/MyInteger")
local integer=mc.mcRegGetValueLong(regHandle)
local integer=integer/2.07
This time I stored the same number (6789) but as an integer by using SetValueLong(). Note that I tried storing the value 6789.1234 using the same API
but the actual stored value is 6789, ie the fractional portion is lost, ie stored as an integer. Interestingly the division works but returns a real value, ie with
a fractional component. It suggests that the integer value was re-cast as a real number and then the division is completed.

This is a common feature of Lua, being essentially type free, is that re-casts happen behind the scenes often transparently to the user. None the less there are at least three
distinct data types that can be stored in a register. You have to be aware of when Lua re-casts......and that has caused me a little grief from time to time.

Craig

425

Mach4 General Discussion / Re: Doing math to DRO values

« on: December 01, 2022, 02:26:47 PM »

Hi,
to assign a register:
1) Open the Configure/Plugins/Regfile
2) Use the green cross checkmark to generate a new instance register
3) Give it a unique name, an inital value if required and whether you want it persistent. Its a handy feature that means the register is saved in the .ini file
on shutdown and the register is restored when you next start up Mach. Very handy!

To see that the register is properly configured, its value and if you want to manually edit it then:
1) Open Diagnostic/Regfile
2) Expand the instance registers, that is iRegs0 with the '+' checkmark

Generally global data in say the GUI cannot be accessed by the Gcode Interpreter because the GUI and Interpreter are different chunks and only one can be active.
A register on the otherhand can be shared across different chunks and between modules. Registers are the true global variable.

To access the register from code:

Code: [Select]

local RegHandle=mc.mcRegGetHandle(mInst,"iRegs0/MyRegister")
local Value=mc.mcRegGetValue(RegHandle)
If you have problems with accessing registers it is usually a fault with the string description of the register 'iRegs0/MyRegister' This string has to be exactly right, letter and case
or you will not get a valid handle. Its highly worthy to put a code test after the GetHandle API call to ensure that you have a non-nill handle....or you will crash.

Craig

426

Mach4 General Discussion / Re: Doing math to DRO values

« on: December 01, 2022, 12:59:44 PM »

Hi,
pound variables are defined within Mach, you cannot o my knowledge assign a pound variable.
What you can do however is define a register. The register can contain a data variable, either numeric or string.
Your DRO would simply display that value.

Craig

427

Mach4 General Discussion / Re: Doing math to DRO values

« on: November 30, 2022, 10:20:16 PM »

Hi,
a DRO is a visual representation of a numeric quantity in Mach. If you want to do some calculation then get the value, almost certainly stored in a pound variable,
not the visual string in the DRO.

What DRO are you trying to read?

Craig

428

General Mach Discussion / Re: z axis always short by the same value

« on: November 28, 2022, 10:29:15 PM »

Hi,
what is the resolution of your machine?. It rather sounds like its 0.025mm in which case the machine is always just one step short.
I have seen that before, usually a mix-up between pull-up verses pull-down, and as a consequence the machine actually does 999 steps
when you commanded it to do 1000 steps.

Craig

429

Mach4 General Discussion / Re: First tests with Smooth Stepper and Mach4 2.500

« on: November 28, 2022, 02:20:11 PM »

Hi,
ALL Windows PCs have a buffered motion system, with the motion buffer usually in the range of 100-300ms. A secondary source of latency is the
reporting time, the same as we have been discussing, the plugin frequency. Typically 5-50ms. Given that the reporting delay is much shorter it is very
easy to be unaware of it, the motion buffer is often noticable.

before buying a Pokey

Have you enquired of PoKey's whether they have a Mach4 plugin for data IO alone, ie NOT a motion controller? Without such a plugin a board would be useless
so you should establish that it WILL do as you want BEFORE you buy.

I wanted to try the SmartASD that I have in my drawer...

I have no idea what a SmartASD is. I can't find anything online about them. Does it have a Mach4 plugin? If not then its no good to you.

1-How do I tell Mach4 that I want to use analog control for red and pink boxed controls?

Each of those controls have a series of functions and actions which in combination cause them to work. If you inspect then in Screen Edit mode you can
see how they are arranged. You would probably retain the same basic structure but swap some of the built-in Mach code for your own code.

2-how do you assign the keys of the PC keyboard in Mach4 to the functions with the yellow box?

There is a good video that has been posted by Daz-the-Gaz about the use of the keyboard plugin which addresses that question.

https://www.machsupport.com/forum/index.php?topic=31585.0

Craig

430

Mach4 General Discussion / Re: Units/Rev readout in Mach4?

« on: November 27, 2022, 02:19:22 PM »

Hi,

What variable or register og function would give me the feedrate and the  spindlespeed?
And would the calculation just be: feed divided by ( revolution multiplyed by number of flutes) ?

The raw data from which you would calculate the feed/rev is stored in registers within Mach. They are commonly called pound variables, and can be viewed/edited at:

Diagnostic/Regfile/#Variables.

I have composed various lists which include the assignment of (some) pound variables:

https://www.machsupport.com/forum/index.php?topic=40051.0

Craig