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5 Synchronization on VARAN fieldbus
In order to ensure the data consistency when accessing to the dual port memory, the
internal calculation cycle must be synchronized to the external VARAN cycle.
For this, the external cycle time is defined by the parameter fb25. A PLL shifts the internal
calculation grid accordingly. If the synchronization is completed successfully, the syn-
chronous operation is shown over the VARAN status LED. See
Id-Text
Name
Parameter index
fb25
cycle time
0x2199
Meaning
Default of the external fieldbus cycle time
Type
Variable
Data length
16 bit
Access
read / write
Coding
0...16000 μs
Standard value: 0 μs
Note
Value is not saved and always writing after switching on the unit.
Only integer multiples of 1000 μs are accepted.
Id-Text
Name
Parameter index
fb26
set sync level
0x219A
Meaning
Maximum permissible deviation of internal to external cycle time
for which the communication is rated to be synchronous.
Type
Variable
Data length
16 bit
Access
read / write
Coding
0...100 μs [multiplier: 1, divisor: 10, offset: 0]
Standard value: 2 μs
Note
-
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SyNCHRONIzATION ON VARAN fIeLDbUS
Содержание COMBIVERT CONTROL G6 VARAN
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