Delta Tau GEO BRICK LV 사용자 설명서

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Turbo PMAC Family Overview 

Turbo PMAC can handle all of the tasks required for machine control, constantly switching back and 
forth between the different tasks thousands of times per second.  The major tasks involved in machine 
control are summarized here. 

The most obvious task of Turbo PMAC is executing sequences of motions given to it in a motion 
program.  When told to execute a motion program, Turbo PMAC works through the program one move at 
a time, performing all the calculations up to that move command (including non-motion tasks) to prepare 
for actual execution of the move.  Turbo PMAC is always working ahead of the actual move in progress, 
so it can blend properly into the upcoming move, if required.  See the Writing a Motion Program section 
for more details. 

The sequential nature of motion program suits it well for commanding a series of moves and other 
coordinated actions; however these programs are not good at performing actions that are not directly 
coordinated with the sequence of motions.  For these types of tasks, Turbo PMAC provides the capability 
for users to write “PLC programs.” These are named after Programmable Logic Controllers because they 
operate in a similar manner, continually scanning through their operations as fast as processor time 
allows.  These programs are very useful for any task that is asynchronous to the motion sequences.  See 
the Writing a PLC Program section for more details. 

In an automatic task that is essentially invisible to the Turbo PMAC user, Turbo PMAC performs a servo 
update for each motor at a fixed frequency (usually around 2 kHz).  The servo update for a motor consists 
of incrementing the commanded position (if necessary) according the equations generated by the motion 
program or other motion command, comparing this to the actual position as read from the feedback 
sensor, and computing a command output based on the difference.  This task occurs automatically without 
the need for any explicit commands.  See the Setting up the Servo Loop section for more details. 

If Turbo PMAC is requested to perform the commutation for a multiphase motor, it will perform 
commutation updates automatically at a fixed frequency (usually around 9 kHz).  The commutation, or 
phasing, update for a motor consists of measuring and/or estimating the rotor magnetic field orientation, 
then apportioning the command that was calculated by the servo update among the different phases of the 
motor.  This task occurs automatically without the need for any explicit commands.  See the Setting up 
Commutation section for more details. 

Turbo PMAC regularly and automatically performs housekeeping tasks that make sure the system is in 
good working order.  These tasks include the safety checks, such as following error limits, hardware 
overtravel limits, software overtravel limits, and amplifier faults, plus general status updates.  They also 
include the update of the watchdog timer.  If any problem in hardware or software keeps these tasks from 
executing, the watchdog timer will trip, and the card will shut down.  See the Making an Application Safe 
section for more details. 

Turbo PMAC can communicate with one or more host computers at any time, even in the middle of a 
sequence of motions.  Turbo PMAC will accept a command, and take the appropriate action – putting the 
command in a program buffer for later execution, providing a data response to the host, starting a motor 
move, etc.  If the command is illegal, it will report an error to the host.