Reference Manual

Turbo PMAC/PMAC2 Software Reference

Turbo PMAC On-line Command Specification 254

TURBO PMAC ON-LINE COMMAND SPECIFICATION

<CONTROL-A>

Function: Abort all programs and moves

Scope: Global

Syntax: ASCII value 1D, $01

This command causes all closed-loop motors in Turbo PMAC to begin immediately to decelerate to a

stop, aborting any currently running motion programs. It also brings any open-loop enabled motors to an

enabled zero-velocity closed-loop state at the present position. If global I-variable I36 is set to 0, it will

also enable any disabled motors, bringing them to a zero-velocity closed-loop state at the present position.

However if I36 is set to 1, it will have no effect on disabled motors; the <CTRL-E> command should be

used for these instead.

Each closed-loop motor will decelerate from its present command velocity to zero velocity at a rate

defined by its own motor I-variable Ixx15. Note that a multi-axis system may not stay on its programmed

path during this deceleration. If the time-base (override) value used by a motor is exactly 0% when the

<CTRL-A> command is given, the motor will abort at the present position even if the command velocity

is not zero; otherwise a ramp-down trajectory will be computed using Ixx15 and executed using the

override value.

A <CTRL-A> stop to a program is not meant to be recovered from gracefully, because the axes will in

general not stop at a programmed point. An on-line J= command may be issued to each motor to cause it

to move to the end point that was programmed when the abort occurred. Then the program(s) can be

resumed with an R (run) or <CTRL-R> command.

To stop a motion sequence in a manner that can be recovered from easily, use instead the Quit (Q or

<CTRL-Q>), the Hold (H or <CTRL-O>), the Quick Stop (\) or the Halt (/) commands.

When Turbo PMAC is set up to power on with all motors killed (Ixx80 = 0) and with I36 set to 0, this

command can be used to enable all of the motors (provided that they are not synchronous motors

commutated by Turbo PMAC – in that case, the motors should be enabled with the $ or $$ phase-

referencing command).

For multiple cards on a single serial daisy-chain, this command affects all cards on the chain, regardless

of the current software addressing.