10.1.5
What needs to be
Programmed for the
Multiprocessor Mode?
•• To allow the coordinator to coordinate access by the individual
CPUs to the I/O area, you must program data block DB 1. Even
if the CPU does not use I/Os or the IPC flags, a (empty) DB 1
must exist (for more information refer to Section 10.1.6)
•• Data block DX 0 must also exist. Program this so that process
interrupts via input byte IB 0 are disabled and the system interrupts
are activated.
10.1.6
How to Create Data Block
DB 1
For multiprocessing, you must program DB 1 for each CPU. This
establishes the inputs, outputs (byte addresses 0 to 127) and IPC
input and output flags with which each CPU works.
Note
The system program recognizes only the inputs and outputs
defined in DB 1 when it updates the process image!
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 accepts 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.
Multiprocessor Mode
CPU 948 Programming Guide
C79000-G8576-C848-04
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