User Manual
Chapter 6
GFK-1742F
Jan 2020
Non-Programmed Motion
168
6.3
Move at Velocity Command
A Move at Velocity %AQ command is generated by placing the value 22h in the first word of
%AQ data assigned to an axis. The second and third words together represent a signed 32-
bit velocity. Note that the third word is the most significant word of the velocity. Once the
command is given, the %AQ data can be cleared by sending a NULL command or changed
as desired. Move at Velocity will not function unless the servo drive is enabled (Enable Drive
%Q command and Drive Enabled %I status bit are set).
The listing of %AQ immediate commands shows the words in reverse order to make
understanding easier. For example, to command a velocity of 512 user units per second in a
DSM314 configured with %AQ data starting at %AQ1, the following values should be used:
0022h (34 decimal) in %AQ1, 0200h (512 decimal) in %AQ2, and 0 in %AQ3. When the
DSM314 receives these values, if Drive Enabled %I is ON, Abort All Moves %Q is OFF, and no
other motion is commanded it will begin moving the axis at 512 user units per second in the
positive direction using the current Jog Acceleration and Acceleration Mode.
The Drive Enabled %I bit must be ON before the DSM314 receives the immediate command
or an error will occur. Also, if a Move at Velocity command is already in the %AQ data, the
velocity value must change while the Drive Enabled bit is ON for the DSM314 to accept it.
The DSM314 detects a Move at Velocity command when the %AQ values change.
When the DSM314 is performing a Move at Velocity command, it ignores the software end
of travel limits (Pos EOT and Neg EOT). Hardware overtravel limits must be ON if they are
enabled.
A Move at Velocity command can be stopped without causing an error in two ways: a Move
at Velocity command with a velocity of zero, or turning the Abort All Moves %Q bit ON for at
least one CPU sweep.