- Should I expect M5 to stop all spindles, or do I have to get used to using M5 $-1?
- Is it possible to get M4 to work? It doesn't do anything right now.
M5 - I recall some discussion on Github about what should be the default behavior for multi-spindle M5 commands. I found a commit that appears to change M5 to 'stop all spindles', and any of the $ modifiers are for individual spindles.
github.com/LinuxCNC/linuxcnc/commit/01a0...d65486193ead51027c29
Probably want to do some testing yourself.
M4: I
think what's going on is that step/dir spindles require an explicit reverse speed value in the INI file, despite what the manual indicates.
linuxcnc.org/docs/devel/html/config/ini-...:ini:sec:spindle-num
adding
[SPINDLE_1]
MAX_REVERSE_VELOCITY = 550
Might do the trick.
If this doesn't work, the next thing is for you to get used to using the 'halshow' feature in LCNC. This is a simple but powerful tool for debugging since it lets you see what LCNC is doing behind the scenes. In your case, you want to know why M4 isn't working so you should display all the HAL pins which affect the spindle - including the PID pins.
When you open halshow there's a folder tree on the left where you can click on all the pins (real physical pins, or logical pins) in LCNC. Once you select those they will appear on the right in the 'watchlist'. On/off (bit) pins will look sort of like red/yellow LED's, and other pin types will display the value.
What you want is to display all the pins which form the internal logic chain that starts with and M4 command and ends with the mesa stepgen outputting signals to the drive. Figuring out all the pins and how they're logically interconnected is not always straightforward... but it also didn't cost you buckets of money.
This is where coming to terms with HAL is necessary:
All this stuff like this below still makes no sense to me as to what its purpose is.
net spindle1-vel-cmd-rps <= spindle.1.speed-out-rps
'spindle.1.speed-out-rps' is a logical (not physical) pin inside LCNC. When LCNC starts up and reads the HAL file, there are a number of default functions that are automatically loaded. One of these functions is called 'motion.comp', and a description of what it does and all the related pins which are created is located here:
linuxcnc.org/docs/devel/html/man/man9/motion.9.html
If you read through that page, what you find is a list of logical pins which are created when LCNC starts. Once those pins are created, you can do 'stuff' with them by connecting them together. I won't go in to specifics right this minute, but any pin which is connected to spindle.1.speed-out-rps will receive a value that is equal to the commanded rotary-axis spindle speed in revolutions per second.
Hopefully this will click with you soon.
BUT
Assuming you didn't mess things up significantly during your editing, I think there may (still) be at least one bug in Mesact or PNCconf for step/dir spindles.
See where
spindle.1.on is connected to
hm2_7i76e.0.stepgen.04.enable through signal
spindle1-enable?
This connection will result in the stepgen shutting off instantly when the spindle is turned off - no controlled deceleration. This result in a massive BANG! when the motor drive stops dead, and can lead to over-voltage trips in the drive or broken things.
This should have been fixed in LCNC 2.9, but it appears to still be an issue:
github.com/LinuxCNC/linuxcnc/issues/2748
This bug shouldn't affect M4/reverse not working, but I bet your spindle stops HARD right now and doesn't decel gracefully.
