ADLINK PCI-8164 - Manual (Page 107)

Operation Theory 95
4.1.10 Home Return Mode
In this mode, the card is allowed to continuously output pulses
until the condition to complete the home return is satisfied after
writing the command _8164_home_move(). There are 13 home
moving modes provided by the 8164. The home_mode of function
_8164_set_home_config() is used to select whichever mode
is preferred.
After completion of home move, it is necessary to keep in mind
that all related position information should be reset to be 0. The
card has 4 counters and 1 software-maintained position recorder,
including:
X
Command position counter: counts the number of pulse out-
puts
X
Feedback position counter: counts the number of pulse
inputs
X Position error counter: counts the error between command
and feedback pulse numbers.
X
General-Purposed counter: can be configured as pulse out-
put, feedback pulse, manual pulse, or CLK/2.
X
Target position recorder: records the target position. (Soft-
ware mainained)
Refer to section 4.4 for details on the position counters.
After home move is complete, the first four counters will be auto-
matically cleared to 0, however, the target position recorder will
not. Because it is software maintained, it is necessary to manually
set the target position to 0 by calling the function
_8164_reset_target_pos().
In some home mode, the stop position after homing is not at 0
because of deceleration. In this case, users must call
_8164_reset_target_pos() by entering this position.
The following figures show the various home modes: