2 persistent memory, Persistent memory, Appendix – Lenze ECSCAxxx User Manual
Page 377

Appendix
Memories
Persistent memory
l
377
EDBCSXA064 EN 3.2
14.3.2
Persistent memory
32 bytes of data can be stored fail−safe in the persistent memory, so that they are also still
available to the program after mains switching. In contrast to the retain memory, the data
even remains in the persistent memory after a new program download. Saving with C0003
= 1 is not necessary.
ƒ
The persistent memory can only be deleted in the online mode of the DDS by using
the command Online
W
Reset (original).
Access to the persistent memory
Access to the persistent memory is effected via the system variables of the control
configuration, assigning the available 32 bytes to several variables of different data types
at the same time, which enables them to be used in the PLC program according to specific
applications:
Byte
Variable (8 bit)
Variable (16 bit)
Variable (32 bit)
Identifier
Address
Identifier
Address
Identifier
Address
0
VAR_Persistent_by
Byte0
%QB171.0
VAR_Persistent_w
Word0
%QW171.0
VAR_Persistent_dw
DWord0
%QD171.0
1
VAR_Persistent_by
Byte1
%QB171.1
2
VAR_Persistent_by
Byte2
%QB171.2
VAR_Persistent_w
Word1
%QW171.1
3
VAR_Persistent_by
Byte3
%QB171.3
4
VAR_Persistent_by
Byte4
%QB171.4
VAR_Persistent_w
Word2
%QW171.2
VAR_Persistent_dw
DWord1
%QD171.1
5
VAR_Persistent_by
Byte5
%QB171.5
6
VAR_Persistent_by
Byte6
%QB171.6
VAR_Persistent_w
Word3
%QW171.3
7
VAR_Persistent_by
Byte7
%QB171.7
8
VAR_Persistent_by
Byte8
%QB171.8
VAR_Persistent_w
Word4
%QW171.4
VAR_Persistent_dw
DWord2
%QD171.2
9
VAR_Persistent_by
Byte9
%QB171.9
10
VAR_Persistent_by
Byte10
%QB171.10
VAR_Persistent_w
Word5
%QW171.5
11
VAR_Persistent_by
Byte11
%QB171.11
12
VAR_Persistent_by
Byte12
%QB171.12
VAR_Persistent_w
Word6
%QW171.6
VAR_Persistent_dw
DWord3
%QD171.3
13
VAR_Persistent_by
Byte13
%QB171.13
14
VAR_Persistent_by
Byte14
%QB171.14
VAR_Persistent_w
Word7
%QW171.7
15
VAR_Persistent_by
Byte15
%QB171.15