Technical data

With the link editor you specify the following:
➣
The interface number
➣
The assignment between:
– SEND/RECEIVE job numbers ANR (range: 134 to 186). The same
ANR is used both for transmitting and receiving.
– Number of the local service access point (SAP; range 2...54, 56)
➣
Priority of the link.
With the link editor, the link parameters of the
local
station can be selected.
The missing information must be stored in the header of the
corresponding data package; this includes the following:
➣
DSAP (destination SAP) of the remote station
➣
Address of the remote station
➣
Required layer 2 service (SDA, SDN or SRD).
CPU
Control
program
ANR
layer 2
services
CP
SIMATIC S5 PLC
Channel
layer 2
services
SAP
no.
LOCAL SAP
SAP
no.
REMOTE SAP
Control
program
PROFIBUS-compatible L2 station
(REMOTE)
(LOCAL)
Fig. 8.3 Access to Layer 2 Services via Service Access Points (SAPs)
B8976060/02 Free Layer 2 Communication
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