Gmoccapy G54 Offsets

Now taking an interest in the G10 L2/L20 pair of Gcodes.
Cannot make sense of the Documentation against the machine display.
My current job is positioned with its G54 origin having x, y, z values -ve relative to Home.

Parameters #5221, #5222, #5223 are documented as the coordinate system Offsets for G54.
The parameters in the linuxcnc.var file correctly show the G54 origin with -ve values.

But, to set up the machine correctly, I have to swap the signs used with a G10 L2.

When Gmoccapy launches, before homing, the DRO shows the tool position with +ve values.
Then G10 L2 P1 with +ve values loads the DRO with -ve values (CORRECT for this job).

Then conventional Touch-Off and run the job.

Please, is my brained screwed, or is the Documentation misleading ?

John.

My brain is confused.
The sequence in the OP doesn't work.

The only reliable way I can set the machine up is to MDI a G0 with axes values per the Parameters (with the steppers off).

Still trying,
John.

Went back to Axis.
linuxcnc.var has Parameter #5221 = -238.
Ignoring y and z for this description.
Launch Axis, Display is:
- x238,
- G54 x-238.
This shows G54 x correctly as negative, ( whereas Gmoccapy shows G54 x as positive ).

No amount of Touching-Off, G10 L2, G10 L20, etc, by me gets to the final correct values for a job:
- x0,
- G54 x-238.

It appears G10 L2 and G10 L20 assume machine is actually Homed physically, and no amount of data entry can change that.

For jobs, I turn steppers Off, operate the machine controller to the measured table position, then Touch-Off, energize the steppers, and run the job.

Can anyone provide an alternative procedure to set-up the mill ?

John.