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Felixrising edited this page Jun 3, 2014 · 4 revisions

Softserial leverages spare rc pins. This setup requires 'feature ppm' with ppm capable receiver hooked up to rc pin 1

Serial Interface Rx Tx
UART2 RC3 RC4
Softserial #1 RC5 RC6
Softserial #2 RC7 RC8

HoTT telemetry over softserial

Enable HoTT telemetry on softserial port 1 with the following commands:

feature PPM
feature SOFTSERIAL
feature TELEMETRY
set softserial_baudrate=19200
set telemetry_port=1
set telemetry_provider=1

Connect Graupner HoTT receiver as follows

HoTT telemetry TX/RX -> Serial RX (connect directly)
Serial TX -> 1N4148 Diode -(|  )-> HoTT TX/RX (connect via diode)
Receiver Ground -> Flight Controller Ground

The diode should be arranged to allow the data signals to flow the right way
-(|  )- == Diode, | indicates cathode marker.

As noticed by Skrebber the GR-12 (and probably GR-16/24, too) are based on a PIC 24FJ64GA-002, which digitals pins are 5V tolerant.

Note: The softserial ports are not listed as 5V tolerant in the STM32F103xx data sheet pinouts and pin description section. Verify if you require a 5v/3.3v level shifters. The softserial port should not be inverted.

FrSky telemetry over softserial

feature PPM
feature SOFTSERIAL
feature TELEMETRY
set softserial_baudrate=9600
set softserial_1_inverted=1
set telemetry_port=1
set telemetry_provider=0

Connect FrSky receiver as follows

Telemetry port RXD -> Serial TX (connect directly)
Receiver Ground -> Flight Controller Ground

Video demonstration of FrSky telemetry via Softserial

https://www.youtube.com/watch?v=dahGlc3Tf40

Turnigy 9XR wiring details

https://plus.google.com/+DominicClifton/posts/bBLiy4czD8y