Target (end) position in Mxx63 variable

[RomanSolonto]

Greetings.
Turbo PMAC clipper.
I have a trouble with M163 (motor number is one) variable when controller processes the cnc program.
When controller processes positive (more than 0) move command it works fine. But when controller processes negative move command it doesn't work at all!
For example. I load this program:
T1 F3200
G0 X40000 (target position is 40,000)
X0 (target position is 0)
X-40000 (target position is 0 ...)
X0 (target position is 0).

Why is the target position displayed incorrectly?

[steve.milici]

That would be indicative of being on a negative position limit.

The design details of your CNC machine are not known so there could be other issues. You should contact the machine builder for further examination.