FrSky receiver feature chart

For posterity, some details about the current range of FrSky ACCST receivers. Last updated 15th April 2018.

Transmission Modes

There are four transmission modes of FrSky ACCST receivers, from oldest to newest:

• V8 - non-telemetry channel-hopping, upto 8 channels.
• D - stands for "duplex" (meaning two-way). The protocol supports telemetry, and upto 8 channels. Note that the "V*-II" generation of receivers can use this protocol, but do not support telemetry.
• X - uses a more advanced way of communicating between the radio and the receiver (PXX). Supports upto 16 channels and telemetry.
• L - long range, no telemetry, uses PXX modulation, upto 12 channels.

Telemetry

The "V8", "L" and "XM" series of receivers do not support telemetry. The "D" and "X" receivers all support transmission of "received signal strength" (RSSI), but support three different methods of connecting sensors:

• Analog: Up to 2 analog input ports (A1 and A2) for simple voltage-based sensors. Some receivers have A1 internally connected to measure the receiver's voltage, with A2 open for external sensors (e.g. for flight battery voltage).
• Digital: The digital port on D-series receivers allows connection of more complex sensors such as a variometer. Multiple sensors can be connected via a hub.
• Smart Port: This newer mechanism on X-series receivers uses a full-duplex (two way) digital serial communication over a single signal wire. Sensors can be chained together and a hub is not required.

RSSI Out

All models with telemetry will report the Received Signal Strength Indicator (RSSI) to your transmitter. However some receivers can output it through a servo channel, i.e. either a physical PWM output or an SBus channel (see the manual). This generally means sacrificing a channel or some other function of the receiver.

Modulation

• The V8 and D generation receivers both use PPM modulation, which can carry upto 8 channels. Some receivers can output a combined CPPM signal on a 3-pin connector (either dedicated or one of the servo outputs), which is useful for example for multicopter control boards.
• The X generation receivers can use PXX, which has upto 16 channels, lower latency and features such as ModelMatch. Most of these receivers can output combined channels via a separate Futaba S.Bus port. A few are switchable to CPPM too.

Redundancy

The 'R' range of X series receivers (R-XSR, RX6R, RX8R, RX8R PRO, G-RX6, G-RX8, R9, R9 slim) feature a redundancy option.

High Speed servos

Some D-series and X-series receivers have an option for a faster update rate from their PWM servo ports. This is 9ms, compared to the default 18ms.

Stabilisation

The S6R and S8R receivers add a 3-axis stabilisation feature to the X6R and X8R respectively.

Variometer

The G-RX* range are designed for gliders and have an integrated variometer.

FASST receivers

I haven't collated the features for the TF range of FASST receivers but may do in future. Feel free to send me a list of the stats and I'd be happy to add them.