Delta Tau GEO BRICK LV Manuel D’Utilisation

For more information on these moves, look under RAPID-mode moves in the Writing and Executing 
Motion Programs section and in the description of {axis}{data}^{data} motion-program 
statements in the Software Reference manual. 

Open-loop moves, as their name implies, do not do closed-loop position control.  They open up the servo 
loop and just put commands of the specified magnitude on the outputs.  Typically, these are used for 
diagnostic purposes, but they can also be used in the actual applications. 

These moves are executed using the motor-specific O{constant} on-line command, where 
{constant} represents the magnitude of the output as a percentage of Ixx69, the maximum output 
parameter for the motor.  This command may not be part of a motion program, and it may not be given to 
a motor when that motor’s coordinate system is executing a motion program, even if it is not moving that 
motor. 

If Turbo PMAC does not commutate the motor, this command creates a constant signal on the single 
output for the motor.  If Turbo PMAC does commutate the motor, this command sets the magnitude of 
the signal that is input into the sinusoidal commutation algorithm for the motor. 

To do a variable O-command, define an M-variable to the filter result register (X:$AE for Motor 1, etc.), 
command an O0 to the motor to put it in open-loop mode, then assign a variable value to the M-variable.  
This technique will even work on PMAC-commutated motors. 

The PMAC Executive Program tuning section uses the open-loop moves to allow you to diagnose and 
tune amplifier response.