This is a digital communication protocol used in R/C receivers.  It uses digital serial data communication technology to transmit control signals between your receiver and servos.  More than that, it allows us to transmit many channels digitally from the receiver to the flight controller.  SBUS allows us to digitally transmit up to 16 channels per receiver (frsky)  The other advantage of SBUS is that it is a very fast protocol.

CPPM and PWM both have around a 60ms-80ms delay, and SBUS only has a 10ms-20ms delay.-  Many top pilots claim that they can feel the difference.

A single S.Bus cable can carry signals to as many channels as your transmitter can handle. You no longer have to worry about plugging in the wrong servo to the wrong channel, because each servo knows what channel it is dedicated to in advance.

SBUS can be found on the popular Frsky X4R-SB receiver and the protocol was originally created by Futaba, and is found on the Futaba SBUS line of receivers.


  • SBUS is faster than PPM and PWM
  • Different Error Handling
  • Smoother, better resolution RC inputs



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4 replies on “SBus

  • Sergio

    Which flight controller series support sbus? I got an EMAX with OSD, and XSR receiver with the idea to use SBUS (16 CH), but I do not think it supports sbus.

  • jon

    I would like to use an SBus protocol analyzer to view the data stream on my signal
    what type or model name would you reccomend that i use

    thank you

    • Anthony Jacobs

      from here

      To answer the fundamental question upfront: SAE J1939 is a higher-layer protocol (i.e., an add-on software) that uses the CAN Bus technology as a physical layer. In addition to the standard CAN Bus capabilities, SAE J1939 supports node addresses, and it can deliver data frames longer than 8 bytes (in fact, up to 1785 bytes).

      Sbus is a futaba & Frsky serial protocol. It is much simpler than the J1939 protocol.

      From here:
      SBUS Protocol
      A single SBUS message is 25 bytes long an therefore, with the configuration described above, takes 3ms to be transmitted. It consists of the following bytes:

      1 Header byte 00001111b (0x0F)
      16 * 11 bit channels -> 22 bytes
      1 Byte with two digital channels (channel 17 and 18) and “frame lost” and “failsafe” flags
      1 Footer byte 00000000b (0x00)

      So I think the only way for you to make this work is to have some sort of decoder (arduino comes to mind) that takes Sbus input and outputs J1939 messages between your Sbus signal and your linear actuators.

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