openLRSng - new revolutionary firmware for openLRS HW

[kha]

I have been workking for some time on a new firmware for openLRS modules, now it is in a shape that allows me to come public with it.

The openLRSng is based in thUndeadMod v4 code but has been quite totally remade to incorporate a few big changes and make it a lot more readable.

Main features:

• 8 servo channels with 10bit resolution (improved feature others are 8bit)
• jitterless PPM output on RX (selectable via jumpper) (improved feature)
• RSSI output on RX
• remotely settable failsafe
• selectable 'radiorate' to choose between range and performance (new feature)
• immediate recovery from 1 and 2 packet loss

The openLRSng uses AVR hardware timer for PPM input and output so, some changes are needed on existing hardware as a specific pin needs to be used for PPM input and output. This is especially relevant for the TX as the M2 module needs a wire added to bind an unused CPU pin to PPM input.

Please note that this should be considered as beta stage software as very limited testing has been done.

You are welcome to have a look on the code https://github.com/kh4/openLRSng.

[MrBen]

Nice to see someone is taking the project further, there are a couple of OLRS users who are members here.

[bigMouse]

I used OpenLRS for about a year and can verify it worked reliably on 433mHz. Never a glitch, but on 459mHz just too many problems...

[kha]

If weather permits we will do some flying with the new code tomorrow.

--kha

[papa_lazerous]

Interesting, but in all honesty I can say that I won't bother trying it, have already achieved 8km with current firmware and had plenty signal to go further, 5.8ghz video is my limiting factor unfortunately.

Sent from my GT-I9300 using Tapatalk 2

[Martink1974]

8km on 100mw ?

[kha]

The point of this firmware is not to add range but more on making it othetwise better like extending resolution and using timers to avoid jitter.

While doing this I keep the parameters affecting rangi intact so range is not affected.

I'm also looking into adding 'beacon' code so that after link is lost for long time it starts to emit beeps at configurable frequency every 30s or so; not sure if it can be done for sure yet.

--kha via mobile

[papa_lazerous]

8km on 100mw ?

Yes mate, it's in the height distance speed thread. I still had 55% signal strength. Video was getting rough and I was worried about battery to return home but had solid control at all times had it hopping on 6 channels too.

Flytron have released a 1000mw version now, don't know if the code is the same as I've not bought one yet, not sure I will either.

Sent from my GT-I9300 using Tapatalk 2

[kha]

small update, just tested "beacon mode" - this basically turns the RX into distress beacon transmitting signal that can be heard and located with normal PMR walkie when the connection is lost for long period of time.

[kha]

I just pushed a version that adds a distress beacon code onto the receiver.

This feature turns the RX module into beacon transmitter operating at 446.006MHz (≃European PMR channel 1) after failsfafe has been activated for 1 minute.

In the beacon mode the RX transmits a tone burst every 30 seconds.
- 1 sec 500Hz @ 100mW
- 1 sec 250Hz @ ~15mW
- 1 sec 166Hz @ 1mW

During the intermediate ~27 seconds the RX is listening normally.

This signal can be heard with a standard PMR walkie talkie.

I will be adding configuration options for this feature to allow selection of the beacon frequency (and also make the initial time longer ~5min, I just have it short the make testing easier).

Later on I will likely be adding a GPS beacon mode which will transmit the GPS position in morse code. This will of course need the RX to receive GPS information (can be stolen from OSD/autopilot etc.).

[kha]

Updated git code to work on the standard TX modules with no modifications.

As detail I had read the schematic a little too fast and the ICP1 pin is actually used for communication with the RFM22 so the TX module cannot be that easily hacked.