Frsky compatibility

xCometz wrote: FYI,
in some RF front-end chip, like A7700 which in XL7105-D03 module, if you enable both PA and LNA, it goes to suspend mode.
Has anyone opened the XL2500-D03 case and looked for RF front-end chip being used?

Just a shot in the dark if Frsky supports Telemetry - if both LNA and PA is enabled when transmitting, you might be push your tx information back into into the RX buffers of the transceiver. However if you have sufficient cycle time between TX and RX cycles and you flush the RX buffers before the RX sequence begin, you should be ok.

Hi PB

Could it be related to the accuracy of the channel frequency? From the CC2500 datasheet:

CC2500 is highly suited for FHSS or multichannel
systems due to its agile frequency
synthesizer and effective communication
interface. Charge pump current, VCO current and VCO
capacitance array calibration data is required
for each frequency when implementing
frequency hopping for CC2500.

sbstnp wrote:
Anyway, once I have my receivers I'll be able to help with testing the FrSky protocol.

Hi sbstnp

I don't know Frsky receivers and a quick google search did not really help. If we talk about FrSky compatibility, do we talk about the FASST protocol?

Alternatively, which FrSky receivers will be supported by Deviation?

(I have a 600EFL that needs a (Deviation compatible) receiver and needs the "best" long range receiver and protocol available)

RandMental wrote:

sbstnp wrote:
Anyway, once I have my receivers I'll be able to help with testing the FrSky protocol.

Hi sbstnp

I don't know Frsky receivers and a quick google search did not really help. If we talk about FrSky compatibility, do we talk about the FASST protocol?

Alternatively, which FrSky receivers will be supported by Deviation?

(I have a 600EFL that needs a (Deviation compatible) receiver and needs the "best" long range receiver and protocol available)

No, we don't talk about FASST. That's Futaba territory. I think FrSky has some FASST receivers ( like this one ).

The current hopping protocol (well not exactly protocol), more like their technology is called ACCST (Advanced Continuous Channel Shifting Technology).

As far as specific protocols they have V8 (one way, obsolete) and D (current, two way). They also announced PXX and new 12 and 16 channels two way protocol supporting long range communication. This will be supported by their X9D and X12D transmitters, whenever they will be released (they postponed the release a few times already). Supposedly they will have a internal FrSky module and a JR compatible slot on the back.


When PB will fix the current problems with the modules we'll have D protocol compatibility. PB also has the one-way protocol published, but I have no idea what's its status.

I have 2 receivers on the way:

1. FrSky D8R-XP 2.4Ghz Receiver (w/telemetry) - ordered this because it can do sum PPM (CPPM) so I can reduce the number of wires from the receiver to a control board or gyro for example.

2. FrSky VD5M 2.4Ghz 5CH Micro Receiver (Telemetry Capable) - because I am a sucker for micro planes.

Thanks for a good description, sbstnp. I spent time tonight on the Frsky site, have a better understanding now of what they offer. I guess we can use the DHT module if the cc2500 does not work correctly.

If it helps any, I have a DHT module laying around, the toggle switch version, here are some pics of the PCB: www.phdpower.co.za/deviationtx/
Its fairly large, 55x35mm about 10mm height, I can solder it up if someone wants to let me know where some wires may go. The red/yell/black is power and ppm signal, the other 4 wires go to the toggle and bind tactile switch. Then separate is the 2 connections used for the telemetry. I am using a second one in a modded 9x with sky9x m/b which will be passed on when we get the Devo's working

stevecox wrote: If it helps any, I have a DHT module laying around, the toggle switch version, here are some pics of the PCB: www.phdpower.co.za/deviationtx/
Its fairly large, 55x35mm about 10mm height, I can solder it up if someone wants to let me know where some wires may go. The red/yell/black is power and ppm signal, the other 4 wires go to the toggle and bind tactile switch. Then separate is the 2 connections used for the telemetry. I am using a second one in a modded 9x with sky9x m/b which will be passed on when we get the Devo's working

I don't want to side track the thread, so I'll just say this, and if we want to discuss it further we can start a new thread.

The frsky DHT will want more than 3.3v to work as it stands. I have mine wired up to a 2s 900mah battery. The first attempt to get PPM out of the 12s didn't work, I'm not sure if PPM is on the tip, or the second lead of the trainer jack. I'll be using the DHT-DIY module as an external module for the time being. But I use head tracking with my 9x, so I still need to carry them both... If anyone wants to discuss external modules, just start a thread and I'll join in. We'll keep this thread for frsky internal modules....
Cheers

Hi Vlad,

there are 2 RF frontend chip, RFX2401 and RFX2401C, they are almost pin compatible but in RFX2401 pin 5 is TX/RXN (high=TX, low=RX) and pin 6 is CE (high=enable chip), so to make PA on and LNA off pin 5 must be high and CE also high.

In RFX2401C pin 5 is TXEN and pin 6 is RXEN, but unfortunately I couldn't find datasheet of it. It must be some mode in combination of this pins.

If it is like in A7700, it would be:
TX RX
0 0 inhibited
0 1 LNA on
1 0 PA on
1 1 sleep

in other word PA and LNA could not be both enable, if both tied to high (Vcc), it will be in suspend and once the model (with luck, but mostly) bind it can by flying lost control because the signal is too weak.

Maybe there are two type XL2500-D03 module, with RFX2101 ans 2401C

Was this ever sorted?
Or the Frsky and telemetry is still not implemented?

No, I don't think anything has been done on FRSky for awhile now. yeah... me too...

Last I remember PB said that the FrSky protocol works fine using a TX module without a PA (Power Amp), but he can not get it to work reliable on modules with a power amp - he then gave up and moved on to other things.

I guess Vlad's previous two posts with these diagrams indicating different High/Low and CE/enable signals could explain the difficulties he had with PA modules.

I was hoping that something like , www.hobbyking.com/hobbyking/store/uh_vie....asp?idProduct=17205 could eventually be installed on a devo 10. And there's soooo much telemetry available for Frsky. And its actually priced where one could afford it, compared to futabas over inflated prices.

Would be nice to have frsky for flights a bit farther out on the field.
We have atleast two well known "Spectrum Pits" where dsm2 and occasionally dsmx will completely lose signal. FASST and Frsky are completely unaffected in those spots.

Isnt the core of Deviation based on the firmware for the 9x transmitters? Those work just fine with Frsky.

Xermalk wrote: Isn't the core of Deviation based on the firmware for the 9x transmitters? Those work just fine with Frsky.

My understanding is that some 9X concepts and ideas were used, but the actual code is all new. I guess we need to find PB a proper PA based module we can use if we want long distance FRsky options.

Xermalk wrote: I was hoping that something like , www.hobbyking.com/hobbyking/store/uh_vie....asp?idProduct=17205 could eventually be installed on a devo 10.

Couldn't you connect it internally to the trainer port ?

Then choose PPM as protocol ?

I can't see why it wouldn't work.

I have the same module, but because I have a devo12, I have to power the module from a separate 2S battery. But it does work.

If you want to see the telemetry you will need use the FRSky mini LCD device to view the data. Deviation does not read in FRSky telemetry data.