PLC System Start-Up and Program Test
S5-115U Manual
The retentive feature in the RE switch position is determined by an entry in system data word 120
(EAF0
H
):
Figure 4-1. Relevant Bits for Setting the Retentive Feature in System Data Word 120
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
x
x
x
x
x
x
x
x
x
x
x
x
x
Bit
SD 120
0: FY 0 to FY 127 retentive and
FY 128 to FY 255 nonretentive
1: All flags retentive
0: T 0 to T 63 retentive and
T 64 to T 127 nonretentive
1: All times retentive
0: C 0 to C 63 retentive and
C 64 to C 127 nonretentive
1: All counters retentive
x = bits that determine system characteristics
(must not be changed when setting the retentive
feature!)
Bits 3, 4 and 5 of system data word 120 are set to "0" after Overall Reset of the CPU.
You can influence the retentive feature separately for flags, timers and counters by setting these
bits
•
in the restart program (OB20, OB21)
or
•
using the DISP ADDR programmer function (only permissible when the PLC is in the STOP
state!).
You can also determine the retentive feature by setting parameters in DB1 (see Section 11.3).
In the case of Overall Reset, all timers, counters and flags are reset regardless of the switch po-
sition or the contents of system data word 120.
4-6
EWA 4NEB 811 6130-02b
Summary of Contents for SIMATIC S5-115U
Page 6: ...EWA 4NEB 811 6130 02b ...
Page 16: ...EWA 4NEB 811 6130 02b ...
Page 18: ...EWA 4NEB 811 6130 02b ...
Page 26: ......
Page 62: ...EWA 4NEB 811 6130 02b ...
Page 64: ...EWA 4NEB 811 6130 02b ...
Page 67: ......
Page 74: ......
Page 79: ......
Page 80: ......
Page 81: ......
Page 82: ......
Page 83: ......
Page 84: ......
Page 97: ......
Page 98: ......
Page 99: ......
Page 114: ...EWA 4NEB 811 6130 02b ...
Page 280: ...EWA 4NEB 811 6130 02b ...
Page 372: ...EWA 4NEB 811 6130 02b ...
Page 432: ...EWA 4NEB 811 6130 02b ...
Page 442: ......
Page 528: ...EWA 4NEB 811 6130 02b ...
Page 590: ......
Page 591: ......
Page 592: ......
Page 593: ......
Page 594: ......
Page 600: ...EWA 4NEB 811 6130 02b ...
Page 602: ...EWA 4NEB 811 6130 02b ...
Page 604: ...EWA 4NEB 811 6130 02b ...
Page 624: ...EWA 4NEB 811 6130 02b ...
Page 632: ...EWA 4NEB 811 6130 02b ...
Page 644: ...EWA 4NEB 811 6130 02b ...
Page 646: ...EWA 4NEB 811 6130 02b ...
Page 652: ...EWA 4NEB 811 6130 02b ...
Page 654: ...EWA 4NEB 811 6130 02b ...
Page 660: ...EWA 4NEB 811 6130 02b ...
Page 662: ...EWA 4NEB 811 6130 02b ...
Page 666: ...EWA 4NEB 811 6130 02b ...
Page 668: ...EWA 4NEB 811 6130 02b ...
Page 674: ...EWA 4NEB 811 6130 02b ...