XLRS, Connectivity and Interfaces in XLRS devices.

Connectivity XLRS Devices

Most XLRS systems in general have multiple ports for current and future needs.

Depending on the XLRS system can be prepared to work in a radio network in the ISM, Wifi, Bluetooth and cable bands with RCBus (local micro network), ethernet and of course Internet IoT.

Each port has the comand ACL interpreter.

The same ACL command language for all products that can “talk” or communicate with each other or with the operator.

Each port can support several protocols such as Text, Transparent Data Link, Mavlink, RCBus, Modbus, etc.

The communications are multitasking in real time, that is, they can be entering and leaving commands and data through all the ports at the same time.

Compatible with the DMDStudio software, you can configure, control and update the firmware of your devices.

Specialized ports for SPPM (Serial PPM) both input and output.

XLRS systems are compatible with almost all DMD products.

Allows mixed projects of systems in flight and sensor networks on the ground.

It can be connected by radio with a network of DMD smart sensors on the ground (for example for agriculture, security, location, etc.) and forward data to the base in real time.

Types of Interfaces

SPPM Inp & SPPM Out for transmitters.

SPPM Out for receivers.

RF ISM

Radiofrequency for radio Control and telemetry in the ISM bands, 863 – 955Mhz.

Powers up to 1W (+30dBm).

Maximum sensitivity: -116dBm @50kb.

It allows bidirectional communications network at 50Kb or 100kb.

Range LOS: 25Km, 50Km, 100Km and 200Km.

FHSS Spectrum extended by frequency hopping. New algorithm 25mSeg/Hop and fast recovery <0.3s.

Compatible with DMD repeaters (Smart Antennas).

It is basically used to send RC data (Radio Control) at 40Hz.

Send and receive DMD telemetry.

Compatible with protocols: Transparent Data Link, Mavlink, RCBus, ACL, etc.

It allows sending messages and commands in real time simultaneously with the radio control data.

More information on radiofrequency…

Bluetooth

It is used to send or receive data (no video, no sound) from a tablet, Smart Phone or PC to most XLRS systems.

It is an alternative wireless port to USB in XLRS transmitters, releasing the pilot from the base station if he is moving.

You can send the GPS of the plane via Bluetooth to a tablet or smart phone to see the position of the model independent of the base station.

You can select to send and receive Mavlink data for Mission Planner, QGroundControl… on an Android and Windows tablet.

It can be selected to send DMD telemetry.

Master and slave modes.

Range: 7-9 meters.

Baud rate from 4800 to 115200 (Configurable, depending on bluetooth module and XLRS device), in most devices is configured by default: 38400b or 115200b..

Configuration of the Bluetooth module from DMDStudio / Transmitter_Name / BLUE.

To link from the XLRS transmitter to a nearby Smart Antenna (In preparation):

– Releasing to the transmitter or portable base station to use the ISM band with full power.

– It isn’t longer necessary to connect large directional antennas to the transmitter or base station connector.

Wifi

It is an additional wireles port that serves similar to bluetooth but with greater range.

It is good to have several types of ports since sometimes you need to use different combinations.

Alternative port to USB and Bluetooth.

You can send the GPS of the plane to a tablet or smart phone to see the position of the model independent of the base station.

You can select to send and receive transparent data link, Mavlink Telemetry …

It can be selected to send DMD telemetry.

It is used to connect an XLRS system to a Smart Phone, tablet, PC to Ethernet or Internet and share data and remote commands over the network.

Estimated range: 40-50m.

Configuration of the Wifi module from DMDStudio / Transmitter_Name / WIFI.

Like bluetooth, you can link to a Smart antenna (In Preparation):

– Releasing to the transmitter or portable base station to use the ISM band with full power.

– It isn’t longer necessary to connect large directional antennas to the transmitter or base station connector.

USB

It is the port to connect a PC in a very simple way.

Micro-B Connector.

Default Speed: 115.200 bps.

In XLRS devices with battery, normally with internal charger, it is used to charge the battery (configurable).

You can send the GPS of the plane to a tablet or smart phone to see the position of the model independent of the base station.

It can be selected to send and receive transparent data link, Mavlink Telemetry for Mission Planner, QGroundControl…

You can send and receive DMD telemetry.

Automatic bridges with the other ports. From the USB you can send data to:

The device itself and its peripherals.

To any other port, for example the ICM radio.

To any remote device that is connected or in direct mode, with repeater, cellular or IoT.

With the XLRS system almost all devices and modules have USB.

From the USB through the software DMDStudio you can configure and update the firmware of the devices.

RCBus

DMD local bus, initially designed for Radio Control equipment, in recent years, is used in almost all DMD products.

Simple protocol oriented to objects and packages, integrated in the OS Alpha of each device.

It supports text packages and in binary format.

It allows to communicate several CPUs in the same circuit. (For example, the XPAD transmitter has 3 microcontrollers, one central and two for Joysticks).

It allows to communicate and share objects in several devices in a small local network at short distances.

It’s basically a serial port with the TX and RX more the power of the device:

At rest the TX is inhibited. (In some devices that do not allow TX inhibition, a diode can be used between the TX and RX).

Default polarization: 10K to + 3.3V per device.

Chargeability: greater than 32UL.

Maximum length approx: 3 meters.

3 wire interface:

RC connector for servos (Radio Control):

0V (Black or Brown).

+5V (Red). According to equipment it can be + 3.3V.

Data. (White or Orange) TX and RX.

Speed: 115.200bps.

Stereo Jack (XPAD3).

COM

Auxiliary serial ports COM1,2,3….

As a transparent data link data interface, Mavlink telemetry with compatible autopilots such as Pixhawk, PX4, APM.

For specific on-board electronics interfaces.

For equipment expansions:

Most XLRS transmitters have several ports with JST connectors internally, prepared for extensions and other uses, such as when installed as a portable base station in a suitcase.

The XLRS receivers have a COM “MODEM” specific for transparent data Link or Mavlink Telemetry and other protocols and several other, configurable ports.

The USB “CON” is also considered a COM port.

The ports of each XLRS device can be configured from the DMDStudio / DEV / PORT software.

I/O Input / Output

Normally installed on board devices.

By default are ports for RC servos.

The ports are multifunction:

CH7 can be configured as SPPM on the XLRS receivers.

CH8 can be configured with RCBus2 on the XLRS receivers.

Some ports can be configured as voltmeters (A / D).

Others as COM ports (to enter GPS data for example).

Etc.

SPPM Input for Transmitters

Most XLRS transmitters have a Trainer or SPPM input (Pulse PPM or PWM Series) with stereo jack.

The transmitter reads the channels from the SPPM input and can relocate them in the objects of the transmitter (Joysticks, Encoders, sliders …) that are more convenient and then mix (Configurable from DMDStudio).

Up to 16 assignable RC channels (Configurable, default 13).

Applications:

Read RC data from another standard RC transmitter or external equipment with SPPM output.

These RC channels can be mixed with the data (objects) of the XLRS transmitter and uploaded to the UAV.

Trainer mode. Student mode with XLRS Transmitter.

Co-pilot or observer. Connection 2nd XPAD or Standard RC Transmitter.

Connection Head Tracker of video glasses.

More info SPPM Inp…

SPPM Out for transmitters

XPAD2, XPAD3 and GCSD4 as of 2020 have configurable SPPM Output (Master) with up to 16 RC channels.

Applications:
Trainer mode. Master mode with XLRS transmitter.
Co-pilot or observer. Video control cameras, etc. with a 2nd XPAD.
Output for simulator on PC. For example for Aerosim.
Use XPAD as standard Joystick on a PC. (For Mission planner, QGround control or similar).
 
More info SPPM Out....

SPPM Out for receivers

The XLRS Receivers have an SPPM or CPPM output of servos in the CH7 / SPPM, to connect the autopilot input and / or an RC channel expander (Converter 1 SPPM to 13 or 16 PWM channels).

Up to 16 assignable RC channels (Configurable, by default 13).

The SPPM outputs can be activated or used for another function.

Each XLRS receiver (case of redundant receivers) has its own SPPM output with its own configuration that can be redundant or not.

Configuration SPPM output from DMDStudio / SRV / SASG.

More info SPPM Out for XLRS receivers.