Current Tool-number permanent?

A partial solution is to configure as a random toolchanger.
One of the things that RANDOM_TOOLCHANGER does is put the tool in the spindle in pocket 0. This is written to the tool-table, and so the tool is still in the spindle at re-start.
(I think this is the case, experiment with a sim config to be sure)
It seems, however, that your toolchanger is _not_ random, the tool removed from the spindle is put back in its home slot.

I don't know if it is better documented anywhere, linuxcnc.org/docs/2.7/html/config/ini-co....html#_emcio_section

I did try to make the whole system rather better a few years ago, but the work was abandoned about the time of the Machinekit split.
(read here for the system that might-have-been: wiki.linuxcnc.org/cgi-bin/wiki.pl?ToolDatabase

The obvious solution would be to write the tool-in-spindle to disc from inside your sequencer component, but that is unfortunately not possible because the realtime system does not have access to the filesystem.

One way that should be quite reliable might be to have a userspace hal component (probably written in Python) that writes the tool-in-spindle to a disk file every time it see the tool change and a start-up G-code that reads a tool-number from that component and does a G61 and G43.

This is quite a common requirement and it is rather annoying that the system doesn't have it properly built-in.

terkaa wrote:

This seems to handle it too. Or is there any problem with this approach?

Have you checked that the MDI_COMMAND gets called when the Tool-change is inside a G-code program?
(I have a feeling it might not be)

If not, then there is an (actually slightly neater) option that ought to work. You can re-map M6 to save the parameter and then do the M6.

linuxcnc.org/docs/2.7/html/remap/remap.h...g_the_m6_replacement

I don't think you need the python prologs, just
Then a file called change.ngc that contains

terkaa wrote:

emc/rs274ngc/interp_remap.cc:575: REMAP BUG=REMAP=M6 100:REMAP = REMAP=M6 modalgroup=6 ngc=toolchange

Can you paste the whole error message? Looking at the code around that spot (github.com/LinuxCNC/linuxcnc/blob/master...interp_remap.cc#L572) there should be a second error message.


The docs on remap seem to say that what was proposed will work:
linuxcnc.org/docs/2.7/html/remap/remap.h...s_including_tt_m6_tt

terkaa wrote:

Hmmm... I get only:

8199 emc/rs274ngc/interp_remap.cc:575: REMAP BUG=REMAP=M6 100:REMAP = REMAP=M6 modalgroup=6 ngc=toolchange
8199 emc/rs274ngc/interp_remap.cc:575: REMAP BUG=REMAP=M6 100:REMAP = REMAP=M6 modalgroup=6 ngc=toolchange

I have just experimented a bit, and it does seem like you need an O<change> SUB and O<change> ENDSUB in the change.ngc file.

Maybe also an M2, not sure.