VIPA CPU 21 Series, Руководство пользователя

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Manual VIPA CPU 21x Chapter 11 Integrated OBs SFBs SFCs
HB103E - Rev. 05/45 11-49
SFC 235 - SYNCHRON
The SYNCHRON block initializes the synchronization between CPU and
CP during the boot process. For this it has to be called from the starting
OBs. Simultaneously the transition area of the interface is deleted and
predefined and the CP and the CPU agree about the block size.
To avoid long cycle run-times it is convenient to split large data amounts
into smaller blocks for transmitting them between CP and CPU. You
declare the size of this blocks by means of „block size“.
A large block size = high data throughput, but also longer run-times and
therefore a high cycle time strain.
A small block size = smaller data throughput, but also shorter run-times of
the blocks.
Following block sizes are available:
Value Block size Value Block size
0 Default (64Byte) 4 128Byte
1 16Byte 5 256Byte
2 32Byte 6 512Byte
3 64Byte 255 512Byte
Parameter type : Integer
Valid range : 0 ... 255
Description
Parameter
Block size
11x 21x 31x 51x
✓ ✓ ✓