Add external device instruction for raspberry pi/home assistant addon

[WesSec]

To use physical Modbus hat/adapter in EVCC on the same raspberry pi used by home assistant, the config.txt in the boot partition of home assistant should be edited for the device to be available. This instruction adds that information to the docs

Please spell check, German is not my first language and mostly used translator tools and common sense.

Todos

• English translation

[WesSec]

Discussion in: evcc-io/hassio-addon#149

[naltatis]

@WesSec thanks for your PR 🙌

The German translation was in deed a little clunky, I've made suggestions. Can you update the English translation as well?

[WesSec]

Suggestions and reviews have been implemented

[WesSec]

@naltatis can you check this PR again? i think it's good for merge :) Thanks

[naltatis]

Can you add the englisch translation?

[WesSec]

The translation must be set in weblate I guess? i can do that when it's available, Im not very iexperienced in that platform

English Transalation:

How can I use my external adapter/pi-hat in the Home Assistant EVCC addon (Home Assistant OS/Raspberry-pi)?

If your Home Assistant device is located near one of your meters (PV / battery / grid, ...), you can also retrieve the data directly via Modbus (e.g. USB).

To do this, you must activate external devices a setting in Home Assistant, which will make the device available to Home assistant and the EVCC add-on. To do this, comment out or add the line uart = 1 in the config.txt on the Home Assistant OS boot partition.

uart = 1 

After a reboot, your device should be available for the EVCC addon (probably as /dev/ttyS0 or /dev/ttyUSB)