Delta Tau GEO BRICK LV Manuel D’Utilisation
Turbo PMAC User Manual
Executing Individual Motor Moves
221
Jog Commands
The commands to jog a motor are on-line (immediate) commands that are motor-specific; they act on the
currently addressed motor.
currently addressed motor.
Note:
A jog command to a motor will be rejected if the motor is in a coordinate system
that is currently executing a motion program, even if the motion program is not
commanding that motor to move. PMAC will report ERR001 if I6 is set to 1 or 3.
that is currently executing a motion program, even if the motion program is not
commanding that motor to move. PMAC will report ERR001 if I6 is set to 1 or 3.
Indefinite Jog Commands
J+ commands an indefinite positive jog for the addressed motor; J- commands an indefinite negative
jog; J/ commands an end to the jog, leaving the motor in position control after the deceleration. It is
possible for the J/ command to leave the commanded position at a fractional count, which can cause
dithering between the adjacent integer count values. If this is a problem, the J! command can be used to
force the commanded position to the nearest integer count value. (Alternatively, ½-count of deadband
created with Ixx64 and Ixx65 can prevent dithering at fractional count values.
jog; J/ commands an end to the jog, leaving the motor in position control after the deceleration. It is
possible for the J/ command to leave the commanded position at a fractional count, which can cause
dithering between the adjacent integer count values. If this is a problem, the J! command can be used to
force the commanded position to the nearest integer count value. (Alternatively, ½-count of deadband
created with Ixx64 and Ixx65 can prevent dithering at fractional count values.
Jogging to a Specified Position
Jog commands to a specified position, or of a specified distance, can be given. J= commands a jog to the
last pre-jog position; J={constant} commands a jog to the (unscaled) position specified in the
command; J=={constant} commands a jog to the (unscaled) position specified in the command and
makes that position the pre-jog position; J^{constant} commands a jog of the specified distance from
the actual position at the time of the command (J^0 can be useful to take up remaining following error);
J:{constant} commands a jog of the specified distance from the commanded position at the time of
the command.
last pre-jog position; J={constant} commands a jog to the (unscaled) position specified in the
command; J=={constant} commands a jog to the (unscaled) position specified in the command and
makes that position the pre-jog position; J^{constant} commands a jog of the specified distance from
the actual position at the time of the command (J^0 can be useful to take up remaining following error);
J:{constant} commands a jog of the specified distance from the commanded position at the time of
the command.
Jog Moves Specified by a Variable
Jogging moves to a position or of a distance specified by a variable are possible. Each motor has a
specific register (L:$0000D7 for Motor 1, L:$000157 for Motor 2, etc., suggested M-variables Mxx72)
that holds the position or distance to move on the next variable jog command. This register contains a
floating-point value scaled in encoder counts. It should be accessed with an L-format (floating-point) M-
variable. The J=* command causes PMAC to use this value as a destination position. The J^*
command causes PMAC to use the value as a distance from the actual position at the time of the
command. The J:* command causes PMAC to use the value as a distance from the commanded position
at the time of the command.
specific register (L:$0000D7 for Motor 1, L:$000157 for Motor 2, etc., suggested M-variables Mxx72)
that holds the position or distance to move on the next variable jog command. This register contains a
floating-point value scaled in encoder counts. It should be accessed with an L-format (floating-point) M-
variable. The J=* command causes PMAC to use this value as a destination position. The J^*
command causes PMAC to use the value as a distance from the actual position at the time of the
command. The J:* command causes PMAC to use the value as a distance from the commanded position
at the time of the command.
Issuing Commands During Jog Moves
It is permissible to issue a jog command to a motor that is already jogging. On receipt of the new
command, Turbo PMAC will break into the already planned trajectory and create a smooth blend to the
trajectory of the new command as determined by the present acceleration and velocity commands. The
existing trajectory is extended out for Ixx92 milliseconds (default 10 msec) after receipt of the new
command; during this time the new trajectory is calculated. The calculations for the new move must be
able to complete within Ixx92 msec.
command, Turbo PMAC will break into the already planned trajectory and create a smooth blend to the
trajectory of the new command as determined by the present acceleration and velocity commands. The
existing trajectory is extended out for Ixx92 milliseconds (default 10 msec) after receipt of the new
command; during this time the new trajectory is calculated. The calculations for the new move must be
able to complete within Ixx92 msec.
Parameters Used by Jog Commands
Each time one of these commands is given, the acceleration and velocity parameters at that time control
the response to the command. To change speed or acceleration parameters of an active jog move, change
the appropriate parameters, and then issue another jog command.
the response to the command. To change speed or acceleration parameters of an active jog move, change
the appropriate parameters, and then issue another jog command.