Add SDM120 meter type

[andig]

As per mreschka@6c82a0b and mreschka@12dabdd

[andig]

ping @mreschka I'd like to understand if adding SDM120 to this repo would be a good idea. Could you kindly clarify what drawbacks there are using the existing SDM630 meter for SDM120 devices? Are there any:

• logfile errors (due to failing meter queries)?
• UI problems with the web ui (empty rows)?
• API problems (improper handling of null values)?
• other problems?

[andig]

ping @mreschka

[mreschka]

Hi @andig,

sorry, I forgot to respond to your first message, thanks for the ping.

No there are no problems with the sdm630 version für a 120 device. The motivation is performance. The sdm120 supports far less registers and I reduced the scheduler to theses ones only. I have in total 20 sdm120 meters and this boosts the update-rate more than 2 times.

Viele Grüße

Markus

[andig]

Hi Markus,

Thanks for the update, I can certainly see your use case. You're trying to push update rate as high as possible?

I'm looking into adding additional meters and e.g. inverters (#80) which would require to refactor the reading logic. I'm thinking to do block-wise register reading instead of single by single. In #46 I had in mind to do this automatically but #80 suggests that should be done in the meter definition.

If I get around to actually implement something- would you be interested in testing?

[andig]

@mreschka see #83 for an approach to do batch readings. Still needs to be implemented for other meter types.

[J-A-U]

If I get around to actually implement something- would you be interested in testing?

Sure.

[andig]

@J-A-U its not a priority, I'll focus on finishing 0.8 for time being. The infrastructure for batch readings is already implemented though and will lend itself to improve readout speed for any meter type.