Diehl LoRaWAN CMi4160, User Manual

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CMi4160
– LoRaWAN
®
Module
19 02/2021
DIB Field Size Data type Description
5 Rt temp 4 bytes INT16 Return temperature (°C)
025Exxxx = °C, 1 decimal
6 Meter
address
10 bytes According to
M-Bus
EN13757-3
identification
field
Meter address
Byte 0-1 = DIF/VIF code
Byte 2-5 = Meter ID, BCD8
Byte 6-7 = Meter manufacturer
Byte 8 = Meter version
Byte 9 = Device type
7 Error flags 4 bytes INT8 Error and warning flags
01FD17xx
For further information about Error
flags please refer to the meter’s user
guide
Table 13: Payload, message format Combined heat/cooling
6.7.3 METER COMMUNICATION ERROR MESSAGE
The payloads using M-Bus encoded data uses the Function field of the DIF to indicate errors. In this
case it is set to “value during error state” (M-Bus standard EN 13757-3:2013) and the value sent
should not be used. A typical case for this is when the module is unable to communicate with the
meter and retrieve meter values, in which case all the fields in the payload have the DIF indicating
“value during error state”.
In case of erroneous data or if the module is unable to communicate with meter, bit 4-5 of the bit of
the DIF code (first byte of each index field) will be set to 11b. For example, a DIF code of 0x02 will
be set to 0x32 in case of error. (This applies to all message format except JSON.) For message format
JSON, the actual value will be replaced with “null” in case of error state. If no meter communication
is possible at all, all fields have this error indication set.
6.8 DOWNLINK
CMi4160 supports configuration via downlink, i.e. sending commands to an end-device via the
LoRaWAN
®
network. Note that this feature should only be used sparingly due to bandwidth
consideration. Communication via downlink is sent on port 2 and can only be made in a short window
after an uplink transmission from module to server. Therefore, time-critical communication should not
be performed over downlink.