1. I find the naming convention confusing . D9 <- TX. Does that mean, it is the pin with "RX" and a signal coming from TX-line of my IR-TTL read head?
Yep, the TX signal of the sensor is connected to GPIO-3 (D9).
Thus the pin on the ESP is then the RX.
I tried to make it as descriptive as possible, with on the left the ESP pins and on the right the function of the pins on the device.
2. Using Serial 0 - do I have to activate or de-activate Serial port debugging?
Serial 0 is the serial port, which can be connected to 2 different pin sets on the ESP8266.
- Gpio 1/3 (default)
- GPIO 13/15 (called Serial 0 swapped)
Regardless of which pin set is used, it is still Serial0.
Logs (when enabled) will be sent to Serial0.
So if you leave logs enabled (both "Use serial" checked in tools -> Advanced and log level of serial set to other than 0) the logs will also be sent to the connected device.
3. The wiki says something of debugging with telnet. How exactly does this work?
The ESP will start a service on the port you set.
Using a tool like telnet (e.g. using a tool like "Putty") you can connect to the ESP on that port.
This will then show all data received from the serial port and characters you type into it will be sent to the serial port.
4. What's behind the "event processing " setting?
This mainly has to do with support for the RFlink device.
It will change the generated events based on whether it is received from a RFLink device.
Events will be handled in the rules.
5. And whats behind "single eent "setting?
On new values received a task will generate events.
Typically you have an event per task value (e.g. BME280 will output temp/hum/pressure).
With "Single event with all values" you get a single event per task, with all task values.
See: https://espeasy.readthedocs.io/en/lates ... all-values
If you only have a single task value, it effectively does not change the number of events generated, but the event "name" will be changed. See the link to the documentation I gave.
6. The wiki uses port 23, I left the default setting 1234 - correct?
Port 23 is the default telnet port.
You can use whichever port you like, as long as it is not yet used on that device (e.g. port 80 is already used for the web server)
You should not open it to the internet, but just to give another argument to use a port > 1024.
Port numbers below port 1024 are considered to be "privileged" ports. For example; In Linux you cannot create a user process claiming a port below 1024.
Also a lot of ISPs block ports below port 1024.
This all suggests to use a port > 1024, which is the suggested default of 1234.
So that's a lot of text to tell you "you can leave it at default"