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Gcode parameters live inside the interpreter and are not directly accessible from outside the gcode program. However there are ways to expose the values from within the Gcode program.
In your case you could use 'M68 E0 Q#1000' to send the parameter value to the hal pin 'motion.analog-out-00' which you can then connect to your gladevcp display.
The M68 code would need to be called every time after the #1000 parameter is changed in the gcode.


linuxcnc.org/docs/html/gcode/m-code.html#mcode:m68
linuxcnc.org/docs/html/man/man9/motion.9.html

For passive BOBs like the SainSmart ones, the configuration with or without  BOB is Identical

You still need to pay customs if you buy from the EU? Didn't that change two decades ago or so?

Anyway - there are cheap clones of the 7i92 on Aliexpress which work the same way like the original, with original Mesa bitfiles. May be worth trying, but they are going more and more expensive very fast. Or does Aliexpress stuff still disappear in Serbian post?

Hi;

I have a gladevcp panel that I would like to display a counter from a gcode routine. In my gcode I have something like lcnt = lcnt + 1 to track the iteration number of a loop. IF I understand the documentation correctly I could assign this value to a global number parameter, say #1000 by using the syntax #1000 = lcnt.  That all seems simple enough.

Now I would like to:
1. Read the contents of #1000 in a python handler associated with the gladevcp panel and display the value on the panel. (I understand the display part, just not the read part)
2. Know when the value of #1000 changes to update the display

Is this possible? How would I code python to read the value? How could I know if the value has been changed by the gcode? Is there an on_changed signal for variable updates?

Kind regards,
 

In that case, if I do a mesaflash for two Bobs, will the configuration work using only one Bob as the base, for example the p1 port, and the other port directly from the card?How would you configure it for my case?

Unless you can get a MPG with open collector outputs ( that match the SainsSmart BOB inputs ),
you are probably better off connecting the MPG  directly to the 7I92.

 

better solution is always 7i96s, The price of the card is not expensive at all, but the problem is that with customs and transportation, even from Portugal, the price is almost double here in Serbia.

This classic bob is available in our market, so in that case, would it be possible to somehow make mpg wheels work with 100ppr/5v?

Yes, you can use the 5ABOBx2 firmware for the common Sainsmart BOB
and choosing the discover option in pnccconf will allow you to make a
working configuration for that firmware.

On issue with the SainSmart type BOBS is that they have no TTL encoder inputs
Those BOBs have 10v ? sourcing inputs (ground to actuate) which may work with
low resolution encoders with open collector outputs. ( low resolution because those inputs
are fed through slow opto isolators )

thanks, in that case I like the option to flash the card for 2xbob, both bob via a fmale to fmale 26pin cable?...in that case I need for my lathe machine one spindle analog output, one spindle encoder input and xzA config for servos and two independent simulative mpg wheels for x and z. In that case, will the pnccfg and gecko initial configuration give me the ability to meet the above needs, possibly by modifying hal for mpg and spindle encoder?

Yes, the G540X2 configuration supports step/dir on both connectors (8 stepgens total)
The 5ABOB x2 configuration is anothe possibility

You _can_ use the output directly with some limitations.

1. They are 3.3V outputs but can drive 5 V  loada when using in sinking mode
( say drive STEP+ to +5V, drive STEP- to  7I92 STEP)

2. The 7I92 pins can be damaged easily by overvoltages (input output range is -0.3V to +7V)
Its very easy to damage with negative voltages unless there is some current limiting

How do you get a negative voltage with high current? Just connect a GPIO pin to frame ground
that has 1VAC of of HF electrical noise relative to 7I92 ground from axis drives/VFDs
If you use the 7I92 GPIO directly, its best to have a small series resistor to protect against
this issue
 

need help with card configuration through pnccfg or mesact...namely specific question can 7i92tm be used without bob  cards directly and if so what is the initial configuration that should be selected in pnccfg? there is an option for gecko in the menu, is it adequate in case of using two bob cards or some other option. so that both P1 and P2 connectors are functional. thanks?

Wow, those are some pretty hefty files you're working with. 
Thanks for sharing more with us.

I have another question. I select the option to turn on the spindle. Output 27 is the option available, but it doesn't output 24V to turn on the relay and start the engine. The other available outputs (numbers 12, 13, 14, 29, 30, 31) always output 5V. Therefore, I wouldn't be able to connect a relay for the refrigeration pump and other control outputs. I've already changed the input and output functions, but the voltage remains the same.

At work I use a 5axis large format machine, ive had over 100mb files before cutting for ~25 hours. 
It has a tool changer but rarely used since it gets full of crud- crappy gantry design with very little dust extraction.
Much fun!