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Wired M-Bus • Water Meters flowIQ® 2101/3100 TECHNICAL DESCRIPTION
Kamstrup A/S · Technical Description · 55121944_A1_GB_08.2016
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SND_NKE:
Short frame. Normalizes the M-Bus water meter.
Start character
10h
C-field
40h
A-field
xxh or FDh
Checksum
xxh
Stop character
16h
SND_UD:
Long frame, Data to the M-Bus water
meter.
Start character
68h
L-field
xxh
length field = number of data bytes N + 3
L-field
xxh
length field repeated
Start character
68h
C-field
53h
(FCB=0) or 73h (FCB=1) = SND_UD
A-field
xxh or FDh
CI-field
xxh
51h = data send, 52h = secondary address
selection
Data byte 1
xx
:
:
:
:
Data byte 1
xx
Checksum
xxh
Stop character
16h
5.6
M-Bus slave to M-Bus master
RSP_UD: Long frame.
Data to M-Bus Master. See telegram later.
RSP_SKE: Short frame.
Data to M-Bus Master. See telegram later.
ACK:
Single control character.
Data format from M-Bus Master received successfully.
Description of the codes of the individual formats can be viewed later in this document.
Communication takes place in following sequences:
5.6.1
REQ_UD2 -> RSP_UD
To collect meter data, from the M-Bus water meter, an REQ_UD2 is transmitted from the M-Bus Master.
The M-Bus water meter checks the message, and if it is correct, the M-Bus water meter returns with an RSP_UD,
which is meter data packed according to the M-Bus format for RSP_UD.
An example of a RSP_UD datagram can be viewed later in the manual.