Siemens Simatic 6ES7 157-0AD81-0 A0 Series - Structure of the H Status of the IM 157 in Redundant Operation on the S7-400 H

Diagnostics Using the User Program
10-13
DP/PA Link and Y Link Bus Couplings
A5E00193841-011
10.2.5 H status
The IM 157 delivers the H status only if it is connected to the redundant DP master
system of an S7-400H. The H status reports on the status of the active and
passive IM 157. The H status consists of 8 bytes.
Structure of the H status
Byte 160
Bit no.
Length of the diagnostic blockincluding byte 160 (= 8 bytes)
Code for station diagnosis
7
6543210
00001000
1EH: Parameter assignment status (switchover by DP master)
1F
H
: H status of activated IM 157
Code for status message
7
6543210
1001111Byte 161
Bit no.
Byte 162 0 Always “0”
Byte 163
Not applicable
Byte 164
Not applicable
76543210
000 0Byte 165
Bit no.
H status 1: status of the IM 157
1: deactivated
1: activated
1: IM 157 is engaged in data exchange with the underlying slaves
1: Master status: clear
76543210
000 0Byte 166
Bit no.
H status 2: status of the partner IM 157
1: deactivated
1: activated
1: IM 157 is engaged in data exchange with the underlying slaves
1: master status: clear
Byte 167
0 H status 3: always “0”
Figure 10-7 Structure of the H status of the IM 157 in redundant operation on the S7-400H