Reference Manual
Turbo PMAC/PMAC2 Software Reference
Turbo PMAC Global I-Variables 95
Setting this parameter to zero disables the warning following error limit function. If this parameter is set
greater than the Ixx11 fatal following error limit, the warning status bit will never go true, because the
fatal limit will disable the motor first.
If bit 1 of Ixx97 is set to 1, the motor can be triggered for homing search moves, jog-until-trigger moves,
and motion program move-until-trigger moves when the following error exceeds Ixx12. This is known as
torque-mode triggering, because the trigger will occur at a torque level corresponding to the Ixx12 limit.
Bit 0 of Ixx97 should also be set to 1 to enable software position capture, making the value of Ixx97 equal
to 3 in this mode.
At any given time, one coordinate system's status bit can be output to several places; which system
depends on what coordinate system is hardware-selected on the panel input port if I2=0, or what
coordinate system is software-addressed from the host (&n) if I2=1.
The outputs that work in this way are F1LD/ (pin 23 on connector J2 on Turbo PMAC only), F1ER (line
IR3 into the programmable interrupt controller (PIC) on Turbo PMAC PC) and, if E28 connects pins 1
and 2, FEFCO/ (on the JMACH1 connector on Turbo PMAC only).
Note:
The units of Ixx12 are 1/16 of a count. Therefore, this parameter must hold a value
16 times larger than the number of counts at which the limit will occur. For
example, if the limit is to be 1000 counts, Ixx12 should be set to 16,000.
Ixx13 Motor xx Positive Software Position Limit
Range: -2
35
- +2
35
Units: counts
Default: 0 (disabled)
Ixx13 sets the maximum permitted positive position value for Motor xx. It can work in two slightly
different ways.
1. Actual position limit: Turbo PMAC’s housekeeping functions repeatedly compare the actual position
of Motor xx to Ixx13. If the motor is closed-loop, and the actual position is greater in an absolute sense
(not magnitude) than Ixx13, Turbo PMAC automatically issues an Abort command, which causes this
motor to start decelerating to a stop at the rate set by Ixx15. If other motors are in coordinated motion,
they are also brought to a stop at their own Ixx15 rate.
Note:
In this mode, the deceleration starts after the limit has been reached, so the motion
will end outside the limit.
If the motor is in open-loop enabled mode (from an O-command) when it exceeds the Ixx13 limit, it will
be aborted (closed-loop stop). If the limit has already been exceeded, no open-loop commands are
accepted for this motor, regardless of polarity.
While the Ixx13 limit is exceeded, Turbo PMAC will allow no more positive-direction commands,
whether from a programmed move, a jog command, or from the position-following function. However, it
will allow negative-direction commands of any of these types, permitting a controlled exit from the limit.
2. Desired position limit: If bit 15 of Ixx24 is set to 1, enabling desired position limit checking, Turbo
PMAC will compared the desired motor target as calculated by the motion program position – either end
of programmed move, or end of intermediate segment – to the limit. If this target position is not
calculated within the special lookahead buffer, when this position is greater in an absolute sense (not
magnitude) than Ixx13, Turbo PMAC automatically issues an Abort command, which causes this motor
to start decelerating to a stop at the rate set by Ixx15. If other motors are in coordinated motion, they are
also brought to a stop at their own Ixx15 rate.