Halscope Basic questions

I am trying using Halscope but it seems I am not aware of some of its components.

Trigger

Normal
Auto
Force

Level Pos



Level
-9.378

Falling/Rising.


I am not sure when to use in Normal or Auto mode. Don't know what moment click on Force to trigger it.

What position to adjust the level and position slider?

My level value is showing -9.378, what does it mean and how much it should be?


I am trying to see the pid.x.error (commanded - feedback position) from the halscope to tune my axis properly. I read the manual but still not clear about these points.

Have you read the halscope tutorial?

linuxcnc.org/docs/html/hal/tutorial.html#sec:tutorial-halscope

I have read it and still confused when should I click on Force button to trigger it.

In manual it says the trigger position is to set display to show the content of before trigger and after trigger.

What I want to do!

I want to record the overshoot of my x position. To do that I choose pid.x.error pin.
I give the command of 5 mm to move. Run mode set to Normal, Trigger set to Auto, Record length set 4000 samples at 1 khz.

I try to give command of 5 mm with feed 10 mm/sec, when it reaches around 4 then I click to record the overshoot. I really don't know when to click, how to see the overshoot?

To do an auto trigger you will need to select a source at the bottomed right. Usually something like velocity command will work.

Select the level you want the trigger to go off at. This would be above or below the channel that is triggering it. Do you want it triggered when it is rising to this level or falling past this level. Usually the first.

When the source of the trigger meets the level line based on rising/falling selection it will trigger and records a bit before and after this action. The amount to record and how much before or after the trigger is selected by the sliders at the top center of halscope.

When setting up your channels to view and set their gains and levels it is sometimes valuable to set the trigger to "roll" this will run the scope continuously so you can make sure what you are trying to see is in the correct increments.

What's the difference between joint.0.motor-pos-cmd, joint.0.motor-pos-fb, hm2_7i95.0.stepgen.00.position-cmd, and hm2_7i95.0.stepgen.00.position-fb ??????


Image attached, showing very close to eachother but little difference. I am trying PID tuning, need help in setting the parameters like max/min velocity and acceleration for default, axis, and stepgen.

joint.0.motor-pos-cmd is LinuxCNCs commanded position output for Joint 0

joint.0.motor-pos-fb is LinuxCNCs acttual position input for Joint 0

hm2_7i95.0.stepgen.00.position-cmd is the 7I95s stepgen 00 position command input (normally not used)

hm2_7i95.0.stepgen.00.position-fb is the 7I95s stepgen 00 position feedback output