ADLINK PCI-8164 - Manual (Page 134)

122 Operation Theory
4.4.5 Target position recorder
The target position recorder provides target position information.
For example, if the 8164 is operating in continuous motion with
absolute mode, the target position lets the next absolute motion
know the target position of previous one.
It is very important to understand how the software handles the
target position recorder. Every time a new motion command is
executed, the displacement is automatically added to the target
position recorder. To ensure the correctness of the target position
recorder, users need to manually maintain it in the following two
situations using the function _8164_reset_target_pos():
1. After a home move completes
2. After a new feedback position is set
Relatied functions:
X
_8164_reset_target_pos(): Refer to section 6.15