FrSky Protocol question(s)

Story: My DEVO 10 got too old and started to cause lost bindings
I'm looking for a new Tx and interested in Taranis's RSSI telemetry but cant find it localy
I can easily get DEVO 12S for the cost of Taranis++shipping+tax so.......

Questios:
Is Deviation FrSky protocol stable yet? (Will it be as reliable as FrSky Tx itself?)

Will it support telemetry and RSSI?

Which module I need?

How is the quality of DEVO 12S?

Hmm. I'm having range/binding issues with my Devo10 and the A7105 module. Are you seeing these issues with just the CYRF, or with the A7105, or something else?

Anyway: I believe the basic protocol is stable. The third party rewrites tend to either work as well as the original, or not at all. For instance, deviationTx is documented as not working with cheap DSM Rx's if you use more than 7 channels, even though Spektrum Tx's work fine under those conditions.

Telemetry is still being worked on. There is support for RSSI, but it's not been integrated into the main or team repositories yet.

You'll need a CC2500 module for it.

According to PBR's transmitter overview , the 12 has the best quality of any of the walkera Tx's. I'd be interested in knowing where you can get one for the price of a shipped Taranis.

My DEVO 10 has no extra module as I only use WK, DEVO and DSM2. It disconnected from RX2702V 2meters away and my V120D02S had a buggy control(no problem on DEVO F12E)
also I barely reach 30cm at 100ųW.

FYI: I can get 12S+12chRx+Batt+Al case for $370

For Taranis(plus)+8chRx+batt $220
shipping $30 (from HK)
Multi-protocol module (to make it as capable as capable as DEVO 10) $105
Not to mention 20%duty + 7%VAT
Total:$355-450

In fact I like the gun-metal look of 12S

What do you think?

Ok, that's not as good a deal as I thought on the 12S. I wasn't figuring in the cost of the extra module for the Taranis.

And I haven't made up my mind yet either. The Taranis seems to be better built based on the reviews, and the design clearly shows the effect of them having worked with the OpenTx developers, with modern nomenclature on the controls and voice alerts. I also love the idea of being able to add new Rf modules without having to solder them into it.

On the downside, the transmitter modules and cpu aren't as tightly coupled in the Taranis as they are in the 12s, so there are transmitter features you can't get to. I've heard reports that the DMS module doesn't do model matching, and that there's a noticeable lag in the controls. So people are opening it up and soldering in DSM Tx modules rather than using the plug in the back one. And IIUC, PBR stopped working on the deviationTx port to it because of this.

The downside for the 12s is - I'm not fond of the touch screen on my 6s. That may be because it's so small. And I'm not sure how readable the color screen will be in sunlight, though I'm going to find out.

If I were going to make the decision, I think I'd go to the OpenTx forums and ask if they are or will be able to support different protocols on an Rf module by adding software. The TH9X transmitters running OpenTx won't do that, but they have an 8-bit CPU, so the Taranis will do a lot of things they wouldn't do without a hardware upgrade. If the answer is No, then I'd get the 12s because it's going to be more capable in the long run.

Thanks alot for useful info

Now what I want to know before deciding is if I go with 12S, will I be able to use FrSky protocol /w telemetry reliably?

Will it develop problems like my DEVO 10?



Many people say 12S has brighter screen compared to 8S and poor touch screen is not a problem given I have been using DEVO 10 for 2years

FrSky without telemetry should be fine running the latest nightly builds. Telemetry is under development, but you'll have to get someone to make a build of it for you.

How does flying the 10 help with the 12S touch screen? I've been using deviationTx for two years now - first a 7e, then I added a 10, and finally sold the 7e and bought a 6s. The color touchscreen interfaces are radically different from the black and white ones. I find the 6s touch screen frustrating to use, because the controls are small and the screen doesn't seem to be accurate. Using a phone or table stylus doesn't help - they are still to big to use accurately.

mwm wrote: FrSky without telemetry should be fine running the latest nightly builds. Telemetry is under development, but you'll have to get someone to make a build of it for you.

How does flying the 10 help with the 12S touch screen? I've been using deviationTx for two years now - first a 7e, then I added a 10, and finally sold the 7e and bought a 6s. The color touchscreen interfaces are radically different from the black and white ones. I find the 6s touch screen frustrating to use, because the controls are small and the screen doesn't seem to be accurate. Using a phone or table stylus doesn't help - they are still to big to use accurately.

I meant I can just use those 6 buttons but yeah 12S has smaller buttons.

After some Googling I found several discussions about universal module that make me wonder if FrSky DHT DIY module will work.
My problem is will DEVO process unknown telemetry data? RSSI data is neither voltage nor RPM nor temp.

I need RSSI for FPV

Well, the 6s has a smaller screen, so maybe the bigger one on the 12s will be easier to use. You can use the 6 buttons, but they don't work as well on the 6s (and presumably the 12s - it's the same code) as they do on the 10. You have to hit ENT before they work, and it doesn't remember menu positions like it does on the 10 & 7e. The latest team builds have some work on that, so maybe it's better - I'm still running 4.0.1 on the 6s.

If you're talking about the HK DYI module, that should work fine. There is a telemetry capable version of that, but you'll have to figure out how to display the telemetry yourself.

I don't really see a lot of advantage to using either of these over just installing a CC2500. It uses fewer hookups, but you'll have to find them yourself. Maybe if you put this in something like the SLT adapter, so you could avoid having to solder on the 12s.

mwm wrote: FrSky without telemetry should be fine running the latest nightly builds. Telemetry is under development, but you'll have to get someone to make a build of it for you.

So I returned to this...
Where can I get telemetry supported build from? Then the question remains: will that build be reliable? (if I do find one)

I can make a build for you, but you'd be better off asking for one on the FrSky protocol thread . The author should be able to build from the latest source, which I don't have. You can also check with him about current reliability.

mwm wrote: ....
I don't really see a lot of advantage to using either of these over just installing a CC2500. It uses fewer hookups, but you'll have to find them yourself. Maybe if you put this in something like the SLT adapter, so you could avoid having to solder on the 12s.

Did some more research on FrSky protocol and read the frsky thread. More questions come up
1. How many CH will be supported by CC2500 on DEVO12S? AFAIK PPM based module will only do 8CH.
2. Will CC2500+latest nightly support all FrSky prtocol V8, D8, D16, LR?
3. From FrSky thread, it seems like they are still tweaking telemetry plus the build only works on DEVO 10 and 7E while latest nightly does not support telemetry at all....am I right?
So I'm thinking about clipping FLD-02. Is this possible? I mean can I get Txd & Rxd pin for FLD-02 from DEVO12S+CC2500?
4. Any combo would you recommend me? I want DEVO for walkera micros, DSM... for satellites on FBL systems, FrSky for FPV.
PS I'm happy to explore all options.

1. FrSky protocol max channels is 12. However, IIRC the FrSky protocols has issues with lots of channels being maxed out at the same time, so take that number with a grain of salt.
2. it looks like the D, V and LR series all use the same protocol, so they should all work.
3. Half right. The telemetry fixes aren't in any nightlies, but those sources build for the x16 transmitters.
4. I suspect not, but you should ask the people working on the code.
5. If all you want is the DSM/Devo protocols and FrSky, I'd go with a Devo Tx and the CC2500. I can build a Devo12 version based on the last uploaded sources with telemetry support, but newer may be available, and I have no idea where that was forked from the mainline.

1. I read somewhere that they fixed it by increasing frame length by 1ms (not sure)
2. Maybe D,V,LR etc use different binding protocol?

Compatibility

FrSky X-series Module (XJT) etc in LR12 mode (Switch 1 is OFF, Switch 2 is ON)
FrSky Taranis X9D etc. in LR12 mode
L9R receiver does not work with FrSky V8, D8, and D16 Mode.
Note: L9R has a bind protocol that differs from the X series

I dont think they use exactly same protocol especially LR as it only works with XJT module

5. Do you have a tutorial of CC2500 installation?

You may be right. In that case, it may take someone decoding the protocol or bind sequence to get it to work. And there's always the possibility that the manufacturer will do something odd that isn't in deviation support. Like the low-end Spektrum Rx's used in the various all-in-one flight control boards. They work fine on all the spektrum Tx's, but go crazy if you bind them to deviation Tx with more than 7 channels. And of course, deviationTx works fine on the stand-alone specktrum Rx's with more than 8 channels.

There are no specific instructions for adding the CC2500. The module installation page describes the general procedure, tools, etc. It links to the transmitter-specific pages which show where the connections you need on the tx are, and the module list page which provides that information for each module.