It took a week, but I did it.
Support tips (instant response!):
/*
Since the Indicator is a single-channel gateway, you need to configure the ADR to static mode in the custom MAC settings. Our S2100 follows the LoRaWAN v1.0.3, which defines the device to join the network with SF12. So please configure the gateway parameters with SF12, and enable the static mode for ADR on the TTN, and the corresponding ADR data rate index should be set to 0 (DR0) for SF12.
please try to configure the indicator:
Rx channel: 868.3
spreading factor: 12
bandwidth: 125
*/
Done, no result.
I set a trap into interrupt handler and see that every few S2100 resets ( corelation exists!), an IRQ_PREAMBLE_DETECTED interrupt occurs, but there’s no further action.
It seems the SX126 is alive, but the interrupt handler is rejecting or transmission is not correct.
I accidentally put both devices on top of each other and it suddenly worked. For a moment.
The decision — it makes no sense — throw them away.
According to the rules, you should separate the plastic from the electronics
and after opening:
My grandfather told me that some receivers work better with an antenna connected, so I connected it. It started working at once and works without a problem with the settings provided by support.
There is a second LoRa antenna, but there is nothing to connect this one to. (ShortRange alternative ?)
A loose cable can ruin a few days.