How to make rotary 4th axis show in AXIS backplot

I just hooked up an A axis (angular) to my three axis machine on 2.5.3 and I can't get the preview and

backplot to show the rotary motion.


I changed the ini file GEOMETRY and [TRAJ] sections as shown below.

My test program works fine in sim_9axis and properly shows the tool tip rotating around the A axis.

Changing the order of XYZA made no difference.

Is there something else I need to change?



[DISPLAY]

# Name of display program, e.g., tkemc
DISPLAY = axis
GEOMETERY = XYZA

# the above line makes the preview and backplot work properly with 4th axis XYZA AXYZ X Y Z -A or something similar ####
# A does not display backplot of A axis, 9/19/15
# GEOMETRY = XYZABCUVW - Controls the preview and backplot of rotary motion. This item consists of a sequence of axis
#letters, optionally preceded by a "-" sign. Only axes defined in [TRAJ]AXES should be used. This sequence specifies the
#order in which the effect of each axis is applied, with a "-" inverting the sense of the rotation. The proper GEOMETRY string
#depends on the machine configuration and the kinematics used to control it. The example string GEOMETRY=XYZBCUVW
#is for a 5-axis machine where kinematics causes UVW to move in the coordinate system of the tool and XYZ to move in the
#coordinate system of the material. The order of the letters is important, because it expresses the order in which the different
#transformations are applied. For example rotating around C then B is different than rotating around B then C. Geometry has
#no effect without a rotary axis.

[TRAJ]
## number of axes needs to include place holders , if used ##
AXES = 4
COORDINATES = XYZA
HOME = 0 0 0 0

test program- works in sim.
m6 t1 h1 g43
g0 g54 x0 y0 z0 a0
o100 repeat [500]
g91
g1 f800
a180 x1 y1 z-1
a-180 x-1 y-1 z1
o100 endrepeat
m30

I got it working now.

It seems that I need to use the entire string GEOMETRY=XYZABCUVW even though I am not using all of the axes.

I posted too soon- I changed it back to GEOMETRY=XYZ-A and it still works, so I have no explanation.

I am using linuxcnc 2.5.3.

The only other thing that did was to comment out the lines for ngcgui, run the machine and then un- comment them.