Technical data

10.1.4
I/O Flag Assignment and
IPC Flag Assignment in
Multiprocessor Mode (DB 1)
The I/O area of the programmable controller is available only once on
the S5 bus. The I/O area encompasses the addresses
F000H to
FFFFH.
In multiprocessor mode, all CPUs in the programmable controller
access this I/O area "simultaneously". To avoid data being
overwritten, the I/O area must be divided between the individual
CPUs.
For this purpose, you must program
DB 1 for every CPU. In DB 1
you define the
inputs and outputs (byte addresses 0 to 127) and IPC
flag inputs and outputs
each CPU is to work with.
If the CPU does not use any I/O or IPC flags, an (empty) DB 1 must
still be available in multiprocessor mode.
Note
Only the input and output bytes defined in DB 1 will be taken into
account during updating of the process I/O image by each CPU.
10.1.5
How to Create Data Block
DB 1
Inputting or changing DB 1 •• Create/modify DB 1 on the PG using the DB 1 screen form
or
•• by editing DB 1 as a data block on the PG and then transferring it
to the CPU.
Note
The CPU evaluates the entered or changed DB 1 only after a cold
restart!
Using the DB 1 screen form 1. Select the editor for the DB 1 screen form on your PG
(refer to Fig. 10-3).
2. Enter the required values for "digital inputs" etc. as decimal
numbers.
10
Multiprocessor Mode
CPU 928B Programming Guide
C79000-B8576-C898-01
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