Kipp&Zonen COMBILOG Data Logger - Manual (Page 118)

SD: Start-Delimiter (length = 1 byte):
The Start-Delimiter SD identifies the beginning of a telegram. It
can assume the following values in the PROFIBUS-protocol:
telegram
format
request telegram response telegram data field length
SD1 hex 10 hex 10 0
SD2 hex 68 hex 68 1 ... 246 (32)
SD3 hex A2 hex A2 8
Table 11.11 Start-Delimiter (SD) in the PROFIBUS-protocol
LE: Length (length = 1 byte):
The Length LE identifies the length of the telegram with vari-
able data field length (SD2-telegram) and comprises the char-
acters from DA to DataUnit. Thus it corresponds to the length
of DataUnit+3 and can have values between 4 and 249. In the
PROFIBUS-DP-protocol the length of the data field is generally
limited to 32 bytes. Since the data logger has no telegrams with
a usable data length of more than 32 bytes, the data logger can
also be integrated in bus topologies with DP-protocol.
LEr: Length-Repeated (length = 1 byte):
The Length-Repeated LEr corresponds to the specification
Length LE. It is stated again in the telegram for data protection
control purposes.
Hardware Manual COMBILOG 1022 118