Pin 6 ( software serial Tx pin ) is connected to pin 5 ( softeware serial Rx )
Send character 'J' t to the software serial Tx pin 6
Read that character on software serial Rx pin 5
Print that character on the terminal.
Problem: nothing is printed on the terminal
It looks like SoftSerial.available() is always false.
"If your project requires simultaneous data flows, see Paul Stoffregen's AltSoftSerial library. AltSoftSerial overcomes a number of other issues with the core SoftwareSerial, but has it's own limitations. Refer to the AltSoftSerial site for more information."
you can not write and read using swSerial at the same time. Tx disables interrupts and does not allow anything else to be done while transmitting. There is no hardware buffer at all. Transmission within the same board is not possible (also not with AltSoftSerial btw) Also there is really no point.
srnet: my project doesn't requires simultaneous data flow.
groundFungus: of course if ( newData = true) was a typo, and I changed the compiler warnings in the preferences.
Deva_Rishi: I built that simple circuit in order to learn about software serial and with your explanations I realize that it can't work. I found a small tutorial about software serial that works: Transmit data from the Uno to a Nodemcu board .