RTC
®
5 PC Interface Board
Rev. 1.9 e
10 Commands And Functions
519
innovators for industry
Comments
• For programming the stepper motor signals, see
•
stepper_init
immediately stops all previously started movements of the stepper motor
specified by the
No
parameter.
• The ENABLE signal is merely forwarded and always correspondingly set, but has no
effect on internal operations.
• If
Period
> 0 and
Dir
>= 0, then stepper motor
No
will start a reference movement
with the supplied CLOCK pulse period in the defined direction and the Init status will
get set. The first Clock pulse is only generated after a full CLOCK pulse period.
– If a limit switch is activated right from the beginning, then the controller will attempt
to seek a position within the ±
Tol
range of the current position, initially opposite to
the defined direction, with the limit switch deactivated. If this doesn’t bring success,
then the attempt will terminate. In this case, the SWITCH status bit remains set (see
).
– If a limit switch gets activated during a movement, then the reference movement will
stop there. Afterward, the limit switch position is crossed multiple times to arrive at
an averaged value for this position. Finally, the stepper motor is driven in the oppo-
site direction via a normal set-position movement (Init status reset, Busy status set)
within the tolerance value
Tol
. Here, the DIRECTION status signal changes, whereas
it remains constant during seeking movements with multiple direction changes. Both
the internal position variable (for the current position) and the internal set-position
value will get set to the value defined via the
Pos
parameter. Thus, this value repre-
sents a positional offset by
Tol
with respect to the defined position.
– If
no
limit switch is found (e.g. because no limit switch exists in the defined direc-
tion), then the stepper motor will perform an infinite movement. The command then
returns after
WaitTime
seconds to restore system control to the application. But the
stepper motor’s infinite movement continues until it is aborted via a new
stepper_init
command or
(
Period
= 0). For more on this, see the
section "Terminating Infinite Movements" on page 206
.
• If
Period
= 0,
Dir
< 0 and/or
WaitTime
= 0, then the command returns straight away
to immediately restore system control to the application. You can then call
to check whether the reference movement has completed.
•
Period
= 0 and/or
Dir
< 0 can be used as an emergency stop. When necessary, a previ-
ously started stepper motor movement will get aborted, but no reference movement
will be performed. Here, too, the position variable and set-position value will get set to
the value
Pos
. This value then represents the current stepper motor position. The
DIRECTION signal remains unchanged.
• If
Period
= 0, then the Init and Busy statuses will get reset. No further clock pulses will
be outputted until
Period
is again set to a positive value (which then also affects subse-
quent set-position commands such as
or
RTC
®
4
RTC
®
5 new command
Version info
• Available beginning with version DLL 527, OUT 529, RBF 519
• For older RTC
®
5 boards with DSP version numbers < 2 (
bits #16-23),
:
RTC5_TYPE_REJECTED
).
Ctrl Command stepper_init
