Delta Tau GEO BRICK LV User Manual
Turbo PMAC User Manual
226
Executing Individual Motor Moves
Ix21
Ix20
Ix21
Ix20
Ix21
Ix21
Ix21
Ix21
Ix20
Ix23
Home Complete=0
Home Search
In Progress=1
Home Search
In Progress=1
Home Complete=1
Home Search in Progress=0
Home Search in Progress=0
Trigger
Occurs
Occurs
Net distance from
trigger position
= Ix26
Desired Velocity Zero=1
In Position=1
(when FE in range)
In Position=1
(when FE in range)
Time
Note: Rate of acceleration
limited by Ix19 - can override
Ix20 and Ix21
limited by Ix19 - can override
Ix20 and Ix21
Vel
Homing Search Move Trajectory
Home Command
The homing search move can be executed either through an on-line command (which can be given from a
PLC program using the COMMAND"" syntax) or a motion program statement.
On-Line Command
A homing search move can be initiated with the on-line motor-specific command HOME (short form HM),
for example #1HM. This is simply a command to start the homing search; Turbo PMAC provides no
automatic indication that the move is completed, unless set up to recognize the in-position (IPOS)
interrupt.
PLC program using the COMMAND"" syntax) or a motion program statement.
On-Line Command
A homing search move can be initiated with the on-line motor-specific command HOME (short form HM),
for example #1HM. This is simply a command to start the homing search; Turbo PMAC provides no
automatic indication that the move is completed, unless set up to recognize the in-position (IPOS)
interrupt.
Monitoring for Finish: If monitoring the motor from the host or from a PLC program to see if it has
finished the homing move, it is best to look at the home complete and desired velocity zero motor status
bits, accessed either with the ? command or with M-variables. The home complete bit is set to zero on
power-up/reset; it is also set to zero at the beginning of a homing search move, even if a previous homing
search move was completed successfully. It is set to one as soon as the trigger is found in a homing
search move, before the motor has come to a stop.
finished the homing move, it is best to look at the home complete and desired velocity zero motor status
bits, accessed either with the ? command or with M-variables. The home complete bit is set to zero on
power-up/reset; it is also set to zero at the beginning of a homing search move, even if a previous homing
search move was completed successfully. It is set to one as soon as the trigger is found in a homing
search move, before the motor has come to a stop.
Note:
The home search in progress bit is the inverse of the home complete bit during the
move: it is 1 until the trigger is found, then 0 immediately after. Therefore the
monitoring should also look for the desired velocity zero status bit to become 1,
which will indicate the end of the post-trigger move.
move: it is 1 until the trigger is found, then 0 immediately after. Therefore the
monitoring should also look for the desired velocity zero status bit to become 1,
which will indicate the end of the post-trigger move.
Monitoring for Errors: A robust monitoring algorithm will also look for the possibility that the homing
search move could end in an error condition. Often this is just part of the general error monitoring that is
done at all times, looking for overtravel limits, fatal following errors, and amplifier faults. If an error
does occur during the homing move, it is important to distinguish between one that occurs before the
trigger has been found, and one that occurs after. If the error occurs after, Turbo PMAC knows where the
home position is, and the homing search does not need to be repeated. Once the error cause has been
fixed, the motor can simply be moved to the home position with a command such as J=0.
Buffered Motion-Program Command
The homing search move also can be commanded from within a motion program with the HOMEn
command, where n is the motor number. Note that this command specifies a motor; unlike other motion
program commands that specify an axis move. In a motion program, Turbo PMAC’s automatic program
sequencing routines monitor for the end of the move. When the move is successfully completed, program
execution continues with the next command.
search move could end in an error condition. Often this is just part of the general error monitoring that is
done at all times, looking for overtravel limits, fatal following errors, and amplifier faults. If an error
does occur during the homing move, it is important to distinguish between one that occurs before the
trigger has been found, and one that occurs after. If the error occurs after, Turbo PMAC knows where the
home position is, and the homing search does not need to be repeated. Once the error cause has been
fixed, the motor can simply be moved to the home position with a command such as J=0.
Buffered Motion-Program Command
The homing search move also can be commanded from within a motion program with the HOMEn
command, where n is the motor number. Note that this command specifies a motor; unlike other motion
program commands that specify an axis move. In a motion program, Turbo PMAC’s automatic program
sequencing routines monitor for the end of the move. When the move is successfully completed, program
execution continues with the next command.