EzUHF firmware v1.53 setup guide

By April 21, 2016March 22nd, 2017Application Note

EzUHF firmware v1.53 adds more customisation possibilities to lower the latency throughout all the transmission chainĀ using several techniques:

  • serial input to the Rx JR module from the remote
  • SBus output from the receiver
  • customisable number of transmitted channel
  • synchronisation of the whole transmission chain

It still supports the well tested PPM behaviour and PPM input and output and these can be used in combination with the above settings.

As the setup has more options, it gets a bit more complex to setup so that the transmitter and receiver can talk to each other.

Here is a guide to get the system set up.

Transmitter Setup

Loading the firmware

Depending on the remote and transmitter, you can load one of these firmwares, following the update procedure as described in the manual:

  • standard firmware using PPM
  • race firmware, using the DSMX/DSM2 output from the Taranis, for the JR module.

Configure the connection from the remote

Setup your Transmitter to emit:

  • PPM like described in the manual for PPM firmware
  • DSM2/DSMX output for race firmware. For the Taranis, this currently only supports six channels output.

Check the connection to the remote. In low power mode, turn on the remote.

It beeps some welcome beeps at startup: 3 times for PPM firmware, 4 times for Race firmware. After a short pause, it beeps once if it recognises the signal from the remote.

Configuring the transmission mode

Once the Tx is configured to receive signal from the remote, it can be configured through USB. Note that it needs to be plugged in the remote and the remote powered to respond on USB.

You can set one of the default setup Race or Standard with the button in the main configuration tab. Or you can configure how the controller data is sent over the air in the EzUHF Advanced tab, on the right side of the pane configuring the Tx:

  • number of channels transmitted “RF Channel Count”: less channels means shorter transmission time and less chance of transmission error. Configure the number of control channels you need.
  • Transmission mode: either the standard or race mode. Race mode transmit data synchronously with the remote output, to minimise latency.

The number of channel must match between transmitter and receiver for them to recognise each other.


Receiver Setup

Loading the firmware

The receiver can output control in different formats depending on the firmware:

  • PWM and PPM on multiple servo outputs with the standard firmware
  • SBUS output on servo output 1 for flight controllers supporting SBUS inputs

Configuring the receiver

Set one of the default setup with the buttons on the main page, or set the details in the EzUHF Advanced tab:

  • number of transmitted channels “RF Channel Count”: corresponding to what you set for the transmitter.
  • number of emitted channels “PPM Channel Count” (for PPM, SBUS is always the same 12 channels). This allows to emit more channels than transmitted, to add UPSTAT, RSSI and Link Quality channels.
  • transmission mode: use race mode to synchronise to packet reception for lower latency.

NOTE: transmission race mode outputs data when it receives it from the TX, if nothing is received, it stops transmitting. This mode has NO FAILSAFE, so you should use the failsafe of the flight controller.



Bind the TX to the RX as usual, following the procedure described in the manual.

Servo values

If using race mode, check the center and extremes of the PPM values, for example using CleanFlight configurator Receiver tab, to ensure the minimum/center/maximum values match 1000/1500/2000.

For combinations of PPM and SBUS firmwares, you’ll need to lower the endpoints, as they don’t use the same definition of stick values to output values.