* Update Sonoff 4CH docs
Swap RX/TX in pin list and add a warning about connecting some pins to GND on boot
Tested with `SONOFF 4CH R3 V1.1 2020-04-13`
* Make the warning less intrusive :)
* Small changes from proofreading.
* Proofreading changes.
* Correction from travis checks
* Update guides/getting_started_command_line.rst
Co-Authored-By: Otto Winter <otto@otto-winter.com>
* More proofreading changes.
* More proofreading changes.
* Minor corrections
This is probably the easiest GPIO pin to use on any of the Sonoff devices. Header is already there out of the box so no soldering and it's not used for anything else.
