Siemens SINUMERIK 840D sl Function Manual page 1227

Basic structure in NCK:
Variable value ranges
The following signals are relevant:
Signal
Enable
Funct
S7Var
IVAR1
IVAR2
Error
ErrCode
Basic logic functions: PLC Basic program powerline (P3 pl)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Type 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
A BOOL
A INT
Detailed description
2.12 Block descriptions
Remark
= 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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