Siemens SINUMERIK 840D sl Function Manual page 171

The data is arranged in the link variables memory as follows, with the data format limits
taken into account:
Figure 2-24
Note
Memory structure
The data in the link variables memory is always arranged randomly and may therefore
appear different (although the data format limits will still be taken into account).
Access via a link variable must be programmed as follows, in accordance with the memory
structure defined:
Program code
$A_DLB[0]
$A_DLB[1]
$A_DLW[2]
$A_DLD[4]
$A_DLD[8]
$A_DLD[12]
$A_DLR[16]
See also
Reading drive data via link variables (Page 172)
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Several Operator Panels on Several NCUs, Distributed Systems (B3)
Example: Structure of the link variables memory
Description
; BYTE(1)
; BYTE(2)
; WORD
; DWORD(1)
; DWORD(2)
; DWORD(3)
; REAL
Link communication
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