3.3
Structure of module data messages
The WB169-430 module transmits following two types of messages:
- standard
information message
with status of all variables, broadcasted periodically
- short
alarm message
sent immediately when alarm status has been detected
The module generates these messages either in open, or in encrypted mode.
3.3.1
Iinformation message
Information message
of the module consists from the Wireless M-BUS header (
”
WMBUS Header”), short 4 Byte
M-Bus header and a data block of at least eight data segments with length of at least 39 Byte (it could vary in
reliance on the number of read watermeters and setting of ”INFO” field).
Structure of Wireless M-BUS message header of the WB169-430 module is described in the Table
Table 3: Structure of Wireless M-BUS message header of the WB169-430 module
Name
Length (Byte)
Description/meaning
Length (L)
1
Message length in Byte
Type (C)
1
”Spontaneous User Data”
Manufacturer ID (M)
2
”SFT” (manufacturer code of Softlink)
Address (A)
4
M-BUS Device ID (configurable)
Version (V)
1
M-BUS Version/Generation (configurable)
Medium (T)
1
M-BUS type of medium (configurable)
Application type (Cl)
1
”Slave to Master, 4-Byte header, variable data format”
Wireless M-BUS header contains full identification of the device according to the M-Bus specification (manufac-
turer/medium/version/serial number) and also message type and format of content.
Short 4-Byte M-Bus header of the message application layer contains following data:
•
item ”Access No” that increases by one with each sent message;
•
item
”
Status” that is normally ”00”, value ”04“ (
”
Low Power”) signalizes low battery volatge;
•
item
”
Signature” contains encryption type and parameter (”00 00” means no encryption).
If the message has been re-transmitted (repeated), item
”
Signature” is modified by Wireless M-Bus repeater to ”01
XX” (low bit of the first Byte changes from ”0” to ”1”).
Basic data block consists of 8 - 25 data segments, each of them carries data of one variable. List of variables
transmitted in the information message of WB169-430 module can be found in the Table No.
Table 4: Description of variables of WB169-430 module info-message data block
Order
Variable (description)
Unit
Type
Data format
1
User module description (location)
text
Inst.
Variable (*)
2
Meter 1 ID
Fabric. No.
Inst.
32 bit Integer
3
Meter 1 counter status
m
3
(10
-3
)
Inst.
32 bit Integer
4
Meter 1 alarm flag
number code
Inst.
8 bit Integer
5
Meter 1 RSSI value
number
Inst.
8 bit Integer
6
Internal battery voltage
V (10
-3
)
Inst.
16 bit Integer
7
Transmitting power setting
W (10
-3
)
Inst.
16 bit Integer
8
Processor temperature
◦
C (-1)
Inst.
16 bit Integer
9
”Uptime” from last reset
seconds
Inst.
32 bit Integer
(*) The message contains this data segment only if the ”Info” string is set. Length of the segment depends on the
number of characters in
”
Info” string.
The above presented table describes message content for the case when the only one watermeter is monitored and
the ”Info” string is entered. If the string is not preset, the message contains only minimum number of 8 segments.
If the module reads maximum number of five watermeters, the message contains four segments (ID, status, alarm
flag and RSSI) for each watermeter and the block contains 25 data segments.
Example of INFO message with the maximum number of segments received and decoded by
WMBUS AN4
Wireless
M-BUS signal analyzer, is shown in the figure
WB169-430
18
