> >
> >> originally created by pncconfig.  Should not
> >>> setp   hm2_7i92.0.stepgen.00.control-type     1
> >>> be control-type 0?
> >>>
> >>
> >> No, needs to be 1
> >
> > So what does it need to be for the spindle then?
> 
> Also 1 since you are setting the steprate from the spindle speed
> 
> >
> > The tutorial suggests stepgen is type 0 for step/dir and "ctrl_type" type v
> > for velocity.
> >
> > I haven't found the details on "control-type" in a document yet.
> 
> 
> 
> > hm2_7i92.0.stepgen.05.control-type
> > Perhaps I overlooked it somewhere?
> 
> man hostmot2, stepgen section
> 
Yes but... to quote
http://linuxcnc.org/docs/html/man/man9/hostmot2.9.html#stepgen

"(bit input) control−type
                Switches between position control mode (0) and velocity control 
mode (1). Defaults to position control (0)."

Why then do the XYZA axis have control_type set to 1 when the above snippet 
clearly says position control mode is 0?

Is this then an error in the manual or just poorly explained?  Does LinuxCNC, 
when used to run a milling machine, use velocity control to move the motor and 
somehow also track the position?  

When I wrote my Electronic Lead Screw software that had to track the spindle 
speed the velocity of the Z axis carriage motor was critical and the position 
was really only used to decide when to finish accelerating and when to 
decelerate.  Since the CNC G-Code specifies feed rate and in the case of 
multiple axis the feed rate along the path I can see that this might well be 
the way it's done.  But with the manual stating 0 (position mode) is the 
default and that G-Code tends to change positions but often leave the feed rate 
constant it's a bit confusing.

John



> Peter Wallace
> Mesa Electronics
> 
> 
> 
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