How it Works:

It works in a similar way how a Betaflight Simulator works actually which is a combination of F4/F7 Flight Controller + Reciever. Betaflight has released this Feature from BF3.4 which utilizes STlibrary and STM Processor of the flight controller to convert the Sbus signal from the receiver to a HID (Human Interface Device) Joystick device when Flight Controller is connected to PC with USB cable. The wiring and requirements are much simpler in XSR-SIM and that is what exactly makes it the best Game Controller Gear.

XSR-SIM has a built-in receiver (D16 Mode). The name itself suggests it follows the XSR receiver which is based on the STM32F1 processor. There are other Frsky receivers based on the STM processor, But they are all too old. The XSR is their latest in the series to use STM processor. Perhaps it may be developed from the schematics of some other Frsky receivers. But one thing is sure, it uses STM32 Processor. It is designed in a way that it utilizes the STM32 Chip of the receiver to incorporate USB HID (Human Interface Device) Joystick library so it doesn’t need extra flight controller to act as HID Joystick Device. So in simple words it is a minimized version of Flight controller + Receiver Combo.

You just need to create a Model in the Taranis or Horus Radio and bind the XSR-SIM dongle with it in D16 Mode to make it a Game Controller. We will be covering How to setup the XSR-SIM and Updating the Firmwares in the next Firmware as well as a tear view of explanation.

Specifications:

Size:- 48.2 x 19.1 x 9.2mm

Weight:- 6.2g

Power Requirement:- Around 55mA at 5v

Compatibility Mode:- D16

Support Upto 8 Channels

Support:

For the same reason it has a built-in receiver, it comes in LBT and EU versions. So make sure you choose the right one for your radio if you are planning to buy one. Also, there are firmware released for the Dongle and you can download it from here https://www.frsky-rc.com/xsr-sim/

Pros:

No more long USB cable strung between your PC and Horus or Taranis Radio
Not Inconvenient like running a USB Cable
Lower Latency compared to Betaflight Simulators because it makes use of only 8 Channels
Cons:

The Battery in your Taranis or Horus Radio will drain Much faster than compared to USB connected Setup (It is Transmitting power output, But you can turn off Internal and External Module when connecting via USB Cable)
Will need to update the firmware of the dongle when upgrading Firmware of the Radio
There is no ACCESS firmware released by the Frsky for the XSR-SIM. Hence it cannot be used with the latest Frsky Transmitters running ACCESS protocol

From: https://www.horusrc.com/en/blog/frsky-game-controller/