6 change position or speed on the fly, 1 change speed on the fly, Change position or speed on the fly – ADLINK PCI-8164 User Manual
Page 136: Change speed on the fly

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Operation Theory
4.6 Change position or speed on the fly
The card provides the ability to change position or speed while an
axis is moving. Changing speed/position on the fly means that the
target speed/position can be altered after the motion has started.
However, certain limitations do exist. Carefully study all constraints
before implementing the on-the-fly function.
4.6.1 Change speed on the fly
The change speed on the fly function is only applicable for single
axis motion. Both velocity mode motion and position mode motion
are acceptable. The graph above shows the basic operating the-
ory.
The following functions are related to changing speed on the fly:
_8164_v_change() – change the MaxVel on the fly
_8164_cmp_v_change() –change velocity when the general com-
parator comes into existence
_8164_sd_stop() – slow down to stop
_8164_emg_stop() – immediately stop
_8164_fix_speed_range() – define the speed range
_8164_unfix_speed_range() – release the speed range constrain
The first four functions can be used for changing speed during a
single axis motion. Functions _8164_sd_stop() and
_8164_emg_stop() are used to decelerate the axis speed to 0.