[Grbl_Esp32 Issue#495] Tool measurement

#1 – JensHauser 于 2020-07-26

Is it possible to get to known the
* current Z position in WCS or
* the location after G38.2

in the
void usertoolchange(uint8t newtool)
function?

This could help to perform the calculation between old tool and new tool position

#2 – bdring 于 2020-07-26

Yes,

Look at how reporting.cpp reports these values.

#3 – JensHauser 于 2020-07-27

While learning C and how to Esp32JH/blob/master/GrblEsp32/Machines/4axisxyxz.h”>4axisxyxz.h and

#4 – bdring 于 2020-07-27

I am headed out of town for a week to visit family. I won’t be able to review or test any code. I also can’t donate much time to non standard machines.

Creating custom machine features in GrblESP32 is powerful, but requires a good understanding of GrblESP32 and C++/RTOS development.

Grbl buffers commands. As each command finished, it will accept a new command. If you have 3 commands and there is room in the buffer, it may appear that Grbl instantly executed 3 commands. It just put them in the queue and will execute them when it can. There are ways to force Grbl to wait in a function until the queued commands are done.

You can also create a new task and state machine. The state machine will execute commands and loop around waiting for a state change. The loop’s separate task does not affect the main tasks performance.

===========================================================

I did this machine in 8-bit grbl. I plan to convert it to GrblESP32/

#5 – JensHauser 于 2020-07-31

I´d like to make use of the tool change functionality for me, learn C and contribute to the project in reverse sequence

So I spent many hours with Bart´s advices and hope to bring some benefit.

Output is a basically working manual tool change function with Z probe as user machine (Esp32JH/blob/master/GrblEsp32/Custom/4axisxyxz.cpp”>4axisxyxz.cpp).

How does it work so far?
– Tool change (“Tx M06”) is triggered by typing in ESP3D
– Measure tool length (only once for the first tool)
– Go to tool change position. Do the tool change manually and press “resume”
– Measure tool length of new tool
– calculate G43.1 and set it

Technically?
– The state machine is a RTOS task
– The RTOS task is started in “machineinit” and triggered in “usertool_change” by the initial machine state (an integer value)
– Typing in “T1 M06” is fine, all steps are performed, including G38.2 and G43.1

What´s open?
– There is an issue with the calling function “usertoolchange” while the task is running
– Once the trigger for the task is set, “usertoolchange” returns and goes on with the main g code
– It doesn´t wait for the final state of the task (I know why)
– This behaviour seems to mix up tool change code and regular g code file. Weird moves, of course.

I don’t know what to do in the do/while loop until the final state is achieved. Sleep/time/etc. didn’t work, the machine doesn’t take reliable moves then. Maybe this approach is misleading.

So far I have this code, but it needs improvement (status output and machine moves are out of sync):

“
void usertoolchange(uint8t newtool)
{
newtoolNo = new_tool;
tcstate = TOOLCHANGEINIT; // trigger to let the RTOS task start working.

while (tcstate != TOOLCHANGEIDLE)
{
sleep(25);
}

return;
}
“

Does anybody have an idea how to get back from RTOS task with a final state (TOOLCHANGEIDLE) and then return from “usertool_change” to go on with g code file?

#6 – JensHauser 于 2020-10-02

The Atari example is impressive, but I have the feeling that a comprehensive knowledge about the grbl programming context is necessary to implement this for me.
Is there any plan to implement a wiki page to give some advice to program the tool change/ tool length offset feature individually?

#7 – JensHauser 于 2021-01-10

Hi @bdring,

some time ago we changed thoughts about tool measurement.
I remember you thought about implementing from your recent projects some months ago:

“I did this machine in 8-bit grbl. I plan to convert it to Grbl_ESP32/6 Pack with automatic Z touch and tool length offset compensation in late August (after the dust settles from the 6 Pack controller production)”

I´m not sure about your plans – this enhancement request couldn´t be found on the roadmap.
The link in the youtube video is not working.

Tried on my own (see fork above), it´s working standalone, but I have an issue with multi-tasking. So some more professional review could be helpful.

Maybe it´s a communication thing and it get lost or I misunderstood your timeline/roadmap, would you mind helping out? Thank you.