Technical data

System program
performs
COLD RESTART WARM RESTART RETENTIVE COLD
RESTART
manual automatic manual automatic manual automatic
Table 4-2 continued:
Deletion of
(cont.):
- IPC flags
- Semaphores
- F flags and
S flags
- Timers and
counters
yes
yes
yes
yes
yes
yes
yes
yes
no
no
no
no
no
no
no
no
no
no
no
no
no
no
no
no
Processing of
remaining cycle
in the case of
active BASP
signal
no no yes yes no no
Restart type
determined by
OB 223
COLD
RESTART
COLD
RESTART
MANUAL
WARM
RESTART
AUTO.
WARM
RESTART
MANUAL
WARM
RESTART
AUTO.
WARM
RESTART
Indication of the
restart type at
the programmer
in the ISTACK
control bits
NEUSTA NEUSTA
+ AWA
MWA AWA ANL-6 +
MWA
ANL-6 +
AWA
User interface
OB 20 OB 20 OB 21 OB 21 OB 22 OB 22
1)
DB 0 is always initialized after POWER ON or OVERALL RESET
Definition of the "9th track"
The "9th track" is a list of input and output bytes in the process image
that acknowledged at the last COLD RESTART.
If you program and load DB 1, then following a successful COLD
RESTART, the 9th track contains only the input and output bytes
listed in DB 1.
You cannot access the 9th track with STEP 5 operations.
4.4.4
User Interfaces for Restart The organization blocks OB 20, OB 21 and OB 22 are used as user
interfaces for the different restart types. You can store your STEP 5
program for each restart type in these blocks.
RESTART Mode
CPU 928B Programming Guide
4 - 22 C79000-B8576-C898-01