M-Bus addressing
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MID_M2000_BA_MB_02_1805
4.6
Changing M-Bus response telegram
The module may answer a M-Bus REQ_UD2 (request user data 2) telegram
with one of five different M-Bus RSP_UD (respond user data) telegrams,
(according to EN13757-3 chapter 4.22 table 2):
•
All
•
Instantaneous values
•
Testing
•
Calibration
•
Manufacturing
The telegram is selected by sending the appropriate M-Bus application reset
telegram.
Request (values in hex):
68 03 03 68 73/53 PAddr 50 ChkS 16
set "All" telegram
68 04 04 68 73/53 PAddr 50 00 ChkS 16
set "All" telegram
68 04 04 68 73/53 PAddr 50 50 ChkS 16
set "Instantaneous"
telegram
68 04 04 68 73/53 PAddr 50 90 ChkS 16
set "Testing" telegram
68 04 04 68 73/53 PAddr 50 A0 ChkS 16
set "Calibration" telegram
68 04 04 68 73/53 PAddr 50 B0 ChkS 16
set "Manufacturing"
telegram
Answer to all of the above requests (values in hex):
E5
The next (and all the following) REQ_UD2 requests are then answered with
the selected telegram.
Please note that the RSP_UD telegram setting is not written immediately in
the non-volatile flash memory of the module but only:
•
On the cyclic 24 hours reset
•
Or if a set primary address command has been received and executed
•
Or if the command to write the configuration area to flash has been
received and executed.
4.7
Write configuration area to flash
The module has got a configuration area which holds settings for e.g. the baud
rate option, the primary address, the selected answer telegram etc. These
settings are kept in volatile RAM memory unless they are written in the non-
volatile flash memory. However, since the write cycles of the non-volatile flash
memory are limited, the respective RAM configuration values are only copied to
the flash configuration values every 24 hours (exception: the primary address).
If the user wants to save the configuration immediately in the non-volatile
memory, he may execute the command below:
Request (values in hex):
68 06 06 68 73/53 PAddr 51 00 FE 00 ChkS 16
save configuration to flash
Answer (values in hex):
E5