I got this working on a TuneRx Nano RX/PA with CRSF input via serial.

But PPM input (neither positiv nor negativ) works.

Attached you find the to tested ppm signals. For the first one the low value is about 600mV.

But PPM input (neither positiv nor negativ) works.

Could you check again after this latest fix and let me know. Then I'll merge it after verification.

But PPM input (neither positiv nor negativ) works.

Could you check again after this latest fix and let me know. Then I'll merge it after verification.

Sure!
Polarity of the PPM signal doen't matter?

Polarity of the PPM signal doen't matter?

I plugged mine into the CPPM pin on the JR bay of a TX16S and set the config to PPM output. So it works with that. Theoretically it should work with both polarities.

Polarity of the PPM signal doen't matter?

I plugged mine into the CPPM pin on the JR bay of a TX16S and set the config to PPM output. So it works with that. Theoretically it should work with both polarities.

Still doesn't work, neither with TX16S ppm (neg.) nor with my old handset (tested both neg. and pos.)

As it recognizes correct CRSF input, the hw def should be ok. For the record, here it is for the TuneRC Nano RX/PA:

{"serial_rx":20,"serial_tx":21,"radio_busy":3,"radio_dio1":1,"radio_miso":5,"radio_mosi":4,"radio_nss":7,"radio_rst":2,"radio_sck":6,"power_rxen":18,"
power_txen":19,"power_lna_gain":12,"power_min":0,"power_high":3,"power_max":3,"power_default":3,"power_control":0,"power_values":[-7,-4,-1,1],"led_rgb
":8,"led_rgb_isgrb":true,"button":9}

As it recognizes correct CRSF input, the hw def should be ok. For the record, here it is for the TuneRC Nano RX/PA:

{"serial_rx":20,"serial_tx":21,"radio_busy":3,"radio_dio1":1,"radio_miso":5,"radio_mosi":4,"radio_nss":7,"radio_rst":2,"radio_sck":6,"power_rxen":18," power_txen":19,"power_lna_gain":12,"power_min":0,"power_high":3,"power_max":3,"power_default":3,"power_control":0,"power_values":[-7,-4,-1,1],"led_rgb ":8,"led_rgb_isgrb":true,"button":9}

To use PPM you will need to set serial_tx and serial_tx to the same pin i.e. 21.

As it recognizes correct CRSF input, the hw def should be ok. For the record, here it is for the TuneRC Nano RX/PA:
{"serial_rx":20,"serial_tx":21,"radio_busy":3,"radio_dio1":1,"radio_miso":5,"radio_mosi":4,"radio_nss":7,"radio_rst":2,"radio_sck":6,"power_rxen":18," power_txen":19,"power_lna_gain":12,"power_min":0,"power_high":3,"power_max":3,"power_default":3,"power_control":0,"power_values":[-7,-4,-1,1],"led_rgb ":8,"led_rgb_isgrb":true,"button":9}

To use PPM you will need to set serial_tx and serial_tx to the same pin i.e. 21.

Oh, my bad, didn't know that!
Used the rx pin number (20) for both rx and tx since my adapter cable uses that -> works perfect.

Q: why does it need both definitions to be the same?)

Q: why does it need both definitions to be the same?)

Because we coded it that way. i.e. if the module is internal full-duplex, then why on earth would you want PPM!
PPM would only be for external modules and we co-opt the half-duplex pin into auto-detecting the signal.