Minebea Intec PR 5211 Series, Instrument Manual, Page: 63 / 96

7 ProfiBus interface
For PR 5211/00 and PR 5211/11 only.
7.1 General notes
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 device via the
field bus to the SPS.
7.2 Profibus interface protocol
The interface works with an 8
‑
byte write window and an 8
‑
byte read window for each
weighing point.
The Profibus exchanges its data cyclically with each slave. That means: In each cycle,
8
‑
bytes are written and 8
‑
bytes are read, even if there are no changes to the data
content.
The Profibus protocol ensures the data transport between Profibus master and the 2 x
8
‑
byte data windows. The interface protocol runs under the Profibus and manages the
access to the most varying data via the 8
‑
byte read and write windows.
Note:
All fieldbus data is only valid, if 'Read_Value_Selected' has been reflected.
7.2.1 Data exchange range
Overview
Byte 0, 1, 2, 3 4 5 6, 7
MOSI Write data Read_Value_Select Write_Value_Select Control bits
(control bits)
MISO Read data Read_Value_Selected Status bits
(status bits) Status bits
(status bits)
Write window (MOSI)
Byte Field Description
0 Write data (MSB)
1 Write data
2 Write data
Contains the data to be written,
e.g., analog output.
7 ProfiBus interface Transmitter Series PR 5211
EN-61 Minebea Intec