Siemens SINUMERIK 840Di Function Manual page 1141

Basic structure in NCK:
Variable value ranges
The following signals are relevant:
Signal
Enable
Funct
S7Var
IVAR1
IVAR2
Error
ErrCode
Power Line Basic PLC Program (P3)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
I/O Type Value range
I Bool
I Byte 3 ,4
I Any S7 data area, except
local data
I Int 0..1023
I Int -1 .. 1023
Q Bool
Q Int
Detailed description
2.12 Block descriptions
Remarks
= FC 21 active
3: Read data
4: Write data
Source/destination data storage
area
Position offset
Semaphore byte
Transfer without semaphore: -1
20: Alignment error
21: Illegal position offset
22: Illegal semaphore byte
23: No new data to be read
24: Cannot write data
25: Local data parameterized for
S7Var
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