How to's
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Set the Pi's serial port baudrate to the same baudrate as the serial telemetry data stream coming from the flight control. E.g.
FC_TELEMETRY_BAUDRATE=57600if your flightcontrol sends it's telemetry data using 57600 baud. -
For the onboard Pi serial port leave default
FC_TELEMETRY_SERIALPORT=/dev/serial0, if using an external USB2Serial adapter, setFC_TELEMETRY_SERIALPORT=/dev/ttyUSB0 -
If you want to connect your flight control to the TX Pi and use wifibroadcast for telemetry transmission, leave
TELEMETRY_TRANSMISSION=wbc -
If you have some other means of transmitting the telemetry to the ground (e.g. an LRS with serial downlink or 3DR dongles) choose
TELEMETRY_TRANSMISSION=externalto receive the telemetry stream on the ground Pi serial port. If using external telemetry transmission, also configureEXTERNAL_TELEMETRY_SERIALPORT_GROUND=andEXTERNAL_TELEMETRY_SERIALPORT_GROUND_BAUDRATE=
NOTE: Before Release 1.6 there is a bug and a workaround that can (but not necessarily will) cause telemetry data corruption. Read this for details.
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Choose the telemetry protocol used, Mavlink is default, other options supported are Frsky and Lightweight telemetry (LTM). E.g.:
#define LTM -
Choose graphical OSD options you would like to have enabled in osdconfig.txt. Should be self-explanatory.
Generally, try to configure your flight control so that it does not send out unnecessary large amounts of data to keep the packet rate as low as possible.
The received telemetry data stream will also be saved in text and raw form to an USB memory stick automatically for later review.
- Connect the serial port TX pin of your flight control to the serial port RX pin on the Raspberry. WARNING: The Pi uses 3.3V logic level on the serial ports, make sure your flight control also uses 3.3V. 5V might destroy the Pi serial port! (See https://pinout.xyz/ for pinout).
For Cleanflight/Betaflight/Inav/etc.: Do not send an inverted serial signal, the Pi doesn't support this. When using a Naze32 clone with softserial, disable this on the CLI with e.g. set telemetry_inversion = OFF (may differ depending on firmware used)
- Power the system up, you should see the received data and decoded data counters for telemetry (last two numbers in the RSSI display in the upper left corner) increasing. If the first number stays at zero, there is no telemetry being transmitted/received, re-check wiring, baudrate and flight control settings in that case. If the first number increases, but the second number stays at zero, there is data being received, but it cannot be decoded, usually this is caused by wrong baudrate settings or wrong telemetry protocol chosen.
- Set
TELEMETRY_UPLINK=mavlinkin wifibroadcast-1.txt - Connect Tower App, QGroundControl or Missionplanner etc. via USB-Tethering or Hotspot
- Connect the serial port RX pin of your flight control to the serial port TX pin on the Raspberry. The Pi uses 3.3V logic level on the serial ports, make sure your flight control also uses 3.3V. Flightcontrols which need 5V logic may not be able to detect the 3.3V signal level (See https://pinout.xyz/ for Raspberry pinout).
To quickly change settings on the field, eight different configuration profiles selectable via GPIO pins are supported. This way, DIP switches, 3-way switches or jumpers can be used to change configuration, similar to analog gear.
4 GPIO pins give 16 possible combinations, from wifibroadcast-1.txt to wifibroadcast-16.txt. Just copy over the existing configfile with a new number and make desired changes (e.g. frequency, or camera settings) there. If you want to have a means to know which profile is selected on the TX, you can use the raspivid annotation parameters under EXTRAPARAMS to let raspivid insert the profile number or whatever text you would like into the video stream. On the RX there is currently no display which profile has been loaded.
The GPIO pins are being checked during boot-up, to select a different configuration, simply change the DIP-switch (and power-off and on again if the system was already running during the DIP switch change).
- Connect your android smartphone or tablet via USB to the RX Pi.
- Enable USB-Tethering in the options of your smartphone (note, some smartphones don't support this out-of-the box or seem to have this function disabled, you may need a 3rd party app to make USB-Tethering work with your device)
- Start FPV-VR 2018 app or other app (Tower App, QGroundcontrol etc.) on android device (don't forget to set
FORWARD_STREAM=rawon the RX Pi when using FPV-VR app and to "rtp" when using the other apps)
If you also have a HDMI monitor connected to the RX, you should see a short message at the bottom of the screen when the android device has been detected.
- Set
WIFI_HOTSPOT=Yin wifibroadcast-1.txt to enable the Wifi hotspot - Leave
WIFI_HOTSPOT_NIC=internalif you want to use the internal onboard Wifi adapter of the Pi3 or set it to the MAC address (all lower case, no spaces, dashes or colons) of the wifi adapter you want to use for the Hotspot. - Configure SSID, password and channel in apconfig.txt if desired. Default SSID is "EZ-Wifibroadcast", default password is "wifibroadcast", channel is 1.
- Connect to the Wifi hotspot, if you also have a HDMI monitor connected, you should see a message that the device has been detected.
Note: To not interfere with each other, there must be about 130Mhz of "space" between Hotspot frequency and wifibroadcast video transmission frequency. The internal Pi3 wifi card only supports frequencies from 2412MHz to 2472Mhz, so if using the internal wifi card, it's not possible to use the 2.4G band for wifibroadcast transmission.
Other external cards have not been tested much, but Ralink based sticks seem to work for 5Ghz so far.
Please also note, that "normal" Wifi transmission is by far not as stable as wifibroadcast transmission, so be aware that there might be stuttering or badblocks, disconnects or other typical wifi issues when using the Wifi Hotspot. If you need a reliable video stream on the android device, consider using the Ethernet Hotspot or USB Tethering.
- Set
ETHERNET_HOTSPOT=Yin wifibroadcast-1.txt to enable the Ethernet hotspot - Connect a RJ-45 cable to the Pi Ethernet port, if you also have a HDMI monitor connected, you should see a message that the device has been detected.
EZ-Wifibroadcast automatically stores video and telemetry in a temporary storage while it is being received from the TX. Saving screenshots (in 10s intervals) is also possible by setting "ENABLE_SCREENSHOTS=Y" in wifibroadcast-1.txt.
To save video, telemetry and screenshots to a USB memory stick, simply plug the stick in after you are done flying. After a few seconds, a message should appear and the recorded video will start playing on the HDMI screen while being saved to USB. A message will appear when saving is done.
Currently, recording is limited to ~12 minutes due to the temporary storage being a ram disk. You can set VIDEO_TMP=sdcardto use the sdcard as temporary storage. Boot-up will take a little longer the first timeafter this option has been set, as the temporary storage on the sdcard needs to be prepared first.
WARNING: Due to issues with the linux kernel, this may lead to video stuttering badblocks or video freezing. Use a fast sdcard to mitigate this and test thoroughly before flying!
The R/C link from ground Pi to air Pi uses MSP (MultiWii Serial Protocol). This is also what is being output on the air Pi serial port. To use it with other protocols, you can use an Arduino with code by Anemostec to convert the R/C data from MSP to PPM for example.
Be careful, this feature has not been tested much, RTH or autopilot is recommended. Feature only works with Atheros cards!
On TX and RX Pi:
- set
ENABLE_RC=Y - set
CTS_PROTECTION=Y
On TX Pi:
- For the onboard Pi serial port leave default
RC_FC_SERIALPORT=/dev/serial0, if using an external USB2Serial adapter, setRC_SERIALPORT=/dev/ttyUSB0 - Set the
FC_RC_BAUDRATE=parameter according to your flightcontrol. 19200 is the minimum required.
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Axis mapping to ROLL, PITCH, THROTTLE, etc. may need to be changed.
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#define AXIS0_INITIAL=sets the initial values for the controls. This is necessary, as it is currently not possible to detect the stick positions until they have been moved. For yaw, roll, pitch you probably want 1500, for throttle 1000.
- uncomment the
#define RC_RSSIline
Connect the serial port RX pin of your flight control to the serial port TX pin on the Raspberry. The Pi uses 3.3V logic level on the serial ports, make sure your flight control also uses 3.3V, or it might not reliably detect the serial signal (See https://pinout.xyz/ for pinout).
- Connect Joystick or Taranis in Joystick mode (Taranis needs to be powered before connecting)
- Do a ground test for correct packet reception and signal:
- increase distance to the aircraft until you are at the end of the video range. R/C control should now still work, you should not see lots of Lost packets in the RSSI display in the upper right corner.
- If everything works as expected, fly. Be careful, this feature has not been tested much, RTH or autopilot is recommended
Connect your device either via USB Tethering, Wifi-Hotspot or Ethernet-Hotspot to the Wifibroadcast RX.
FPV_VR app in Playstore
Usage information and source code
Set FORWARD_STREAM=raw in wifibroadcast-1.txt to send a raw h264 stream to the FP_VR app.
- Set
FORWARD_STREAM=rtpin wifibroadcast-1.txt to send a RTP encapsulated h264 stream to the app. - Set video port in Tower app settings to 5000. See here for instructions.
QGroundControl App
Set FORWARD_STREAM=rtp in wifibroadcast-1.txt to send use a RTP encapsulated h264 video stream to the app.
- Click on the eye icon (on the bottom right)
- Now a debug screen appears, select all on the upper bar, delete all parameters and set:
udpsrc port=5000 ! h264parse ! avdec_h264 ! autovideosink sync=false
Set FORWARD_STREAM=raw in wifibroadcast-1.txt to send a raw h264 stream
Gstreamer 32-Bit Windows Gstreamer 64-Bit Windows
Use the following commandline:
gst-launch-1.0.exe udpsrc port=5000 ! h264parse ! avdec_h264 ! autovideosink sync=false
Set FORWARD_STREAM=raw in wifibroadcast-1.txt to send a raw h264 stream
Some people reported the necessity to add the gst-launch-1.0.exe application to their firewall exception list, see this video for more info: https://www.youtube.com/watch?v=eHCfyWhEAvI
Another Option is GStreamerHUD, see Github page here: https://github.com/MovLab2/GStreamerHUD
In case you get an error message that "api-ms-win-crt-runtime-l1-1-0.dll" is missing see here and here
See here for a video:
Install gstreamer using the package management system of your linux distribution
Use the following commandline:
gst-launch-1.0 udpsrc port=5000 ! h264parse ! avdec_h264 ! autovideosink sync=false