title_body: Remap not yet existing uart I have a flight controller that has one uart to little. So i tried to remap SERIAL_TX 5 (That doesn't exitst on the FC) to pin A09, that previously had SERIAL_TX 1, but that doesn't seem to work. I also tried to remap SERIAL_TX 5 to LED_STRIP, but that didn't work either. Is there something else you have to do to get it working?
  
  The commands I used was:
  
  resource SERIAL_TX 1 NONE
  
  resource SERIAL_TX 5 A09
upvoted_answer: Serial ports are hardware based, and cannot be remapped. You can however remap software serial ports. Keep in mind not every pin supports softserial either, as an available hardware timer is required. Typically you can use: 
  
  
  UART TX &amp; RX pins
  PPM Input pins
  LED pins
  Motor PWM output pins
  
  
  If you have one of those free, proceed.
  
  
  Enable softserial from the Betaflight Configurator "Configuration" tab, then click "Save and Reboot".
  
  Go to the "CLI" tab and type "resource SERIAL_TX 11 A09", hit enter, then type "save" and hit enter.
  
  Go to "Ports" tab and assign the feature you want to "SOFTSERIAL1".
  
  
  
  Keep in mind that software serial is limited in terms of how fast it communicate information and the load it puts on the CPU. If you have a very intensive low-latency connection, typically try to avoid use softserial. Softserial is best suited to things like VTX control (smart audio and tramp protocol, etc), GPS, and smart-port telemetry, where latency, speed, or loss of signal during flight isn't an issue. While it can be used for other more system critical links like RC control, I would generally recommend against it, though it is theoretically possible.
  
  Sources:
  https://oscarliang.com/betaflight-soft-serial/
  http://www.multirotorguide.com/guide/guide-how-to-set-up-the-softserial-uart/