G-2
Communications Processor CP 541
EWA 4NEB 812 6188-02
Messages from the connected programmable controller are converted by the
CP 541 to the PROFIBUS services given in Table G-2.
Table G-2
PROFIBUS Services
Communication mode
PROFIBUS service
Priority
PLC-PLC connection
SDA
1
Low priority
Broadcast
SDN
2
Low priority
DP connection
SRD
3
See DIN E 19245, Part
3
1
SDA: Send Data with Acknowledge
2
SDN: Send Data with No Acknowledge
3
SRD: Send and Request Data
PROFIBUS
Services
Service Access Point (SAP) and PROFIBUS Services