Technical data

11.7 L2-DP Diagnostics with the User Program
11.7.1 Overview
To allow you to monitor the data exchange with the configured DP slaves
from the user program, the CPs provide the following functions:
➣
Read out DP station list
The DP station list provides information about the status of all slaves
and has a length of 16 bytes (128 bits). Each bit of the station list
corresponds to one of the possible bus addresses of a DP slave station.
Meaning of the bits
15
76543210
120 127 *)
0
1
76543210
76543210
01234567
8 9 10 11 12 13 14 15
2 - 14
16 - 119
Byte
Bit
Station
address
*) The first and last two bits in the station list are not relevant, since the permitted
station address on the L2 bus must be in the range 1-125
124
Fig. 11.18 Structure of the DP Station List
Bit code Meaning
0 Station is in the cyclic data transfer phase or the station
address is not assigned.
1 Station is not in the cyclic data transfer phase
Distributed I/Os (DP) B89060/02
Volume 1 11 - 40