Home Values Wrong

So here's what happened: I had not used my CNC for a few weeks. Today I powered it up and tried to home it. When I did that, I found that all the home position values are wrong. I was expecting to get 0.000, 0.000, 0.000 after homing, but now I get 30.587, 3.755, 127.641. Un-homing and re-homing gives the same results. I confirmed that the .INI file is set up to home all three axes to zero. And until today, that was exactly what I got.

The method I am using to home is as follows:
-- Jog the axis to its reference mark
-- Select the axis using its radio button
-- Click on the "Home" button
-- Repeat for the other axes

For fun, I went in to the .INI file and changed the X axis home position from 0.000 to 50.000. Then I re-started LinuxCNC and homed the X axis. As soon as I clicked on the "Home" button, the X axis moved rapidly 50 mm in the positive direction. Never saw it do this before.

Any suggestions about where to start troubleshooting?

use the startup code to get all clear in ini section
RS274NGC_STARTUP_CODE = G17 G20 G40 G49 G80 G90 G92 G94 G97 G98

you may delete the VAR file in the mashine folder (its getting renewed on linuxcnc start)

you can also tell you post to clear all ofsets at the end of the G-code
G92.1

BigJohnT:

Thanks for the link. That procedure solved my problem.

Now I will have to crack the manual and work to understand just what was going there...