9. Fieldbus interface | 108
9 Fieldbus interface
9.1 General notes
The PR 5215 can be included under a communication master (e.g. Siemens S7
ProfiBus) as a field bus slave.
The update rate is 50 ms.
The field bus exchanges its data cyclically with each slave. That means: In
each cycle, the entire data range is written and read, even if there are no
changes to the data content.
Concept definition
Term/Abbreviation
Description
Master
Field bus master, usually an SPS
Slave
Field bus device
MOSI
Master Out Slave In = data is written from the SPS via
the field bus to the device.
MISO
Master In Slave Out = data is returned from the de
vice via the field bus to the SPS.
9.2 Scale protocol
The interface works with an
8‑byte
write window and an
8‑byte
read window
for a weighing point.
Note:
All fieldbus data is only valid, if 'Read_Value_Selected' has been reflected.
