Technical data

4.4 RESTART Mode
The RESTART mode is distinguished by the following features:
Transition from STOP
to RUN
The RESTART is the transition from the STOP mode to the RUN
mode.
Restart types The CPU 928B has the following restart modes:
- COLD RESTART (manual or automatic)
- WARM RESTART (manual or automatic)
- RETENTIVE COLD RESTART (manual or automatic -
only with Version -3UB12)
Following a COLD RESTART, the cyclic user program is processed
from the beginning. Following a WARM RESTART, the cyclic user
program is processed from the point at which it was interrupted.
Organization blocks The following organization blocks are called:
for MANUAL or AUTOMATIC COLD RESTART: OB 20
for MANUAL WARM RESTART or RETENTIVE
COLD RESTART: OB 21
for AUTOMATIC WARM RESTART or RETENTIVE
COLD RESTART: OB 22
The length of the STEP 5 start-up program in the OBs is not restricted.
The organization blocks are not time-monitored. Other blocks can be
called in the start-up OBs.
Data handling In each start-up type, the values of counters, timers, flags and process
images are handled differently.
BASP signal The BASP signal (disable command output) is active. This disables all
digital outputs.
Exception: in the test mode, BASP is not activated! (Please see your
System Manual for information on the test mode.)
LEDs on the front panel of the
CPU
RUN LED: off
STOP LED: off
BASP LED: on (except in test mode)
Restart characteristics in
multiprocessor mode
For information on the start-up procedure in the multiprocessor mode,
refer to Section 10.1.7.
4
RESTART Mode
CPU 928B Programming Guide
C79000-B8576-C898-01
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