SBUS does not work

[tilmanb]

Guys I'm confused and desperate. I have no clue what I'm doing wrong but I can't get my Servos working on the FrSky SBUS decoder.

I can connect a battery to the SBUS channel changer and the LED on the decoder light up and I can set up the channels.
But if I hook it up to the SBUS port on the X8R receiver I get nothing. No LED and no servo movements.

I thought it would be straight forward. And it probably is, but what am I not seeing!?

I need this plane flying tomorrow, and I can't hook up the servos differently. The plugs are all glued in and the servos soldered directly on the decoder. (No worries I have another one unmodded that also does not seem to work)

[tilmanb]

I should add that I assigned channel numbers below channel 8. I'm sure that is fine. Or is it not?

[tilmanb]

I also tried binding with a jumper between signal pin 3 and 4.
I don't use channels over 8 and I also don't send them. So I did not think that would make sense. And indeed it made no difference.

[Kilrah]

Is the receiver correctly bound and powered, ie does a servo connected to the main receiver pins work?
BTW why the need for a sbus decoder if you don't have more than 8 channels?

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[tilmanb]

Yes they do

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[tilmanb]

BTW why the need for a sbus decoder if you don't have more than 8 channels?

Because future.
And only one wire per wing.


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[Kilrah]

Does the converter's led light if you connect it to another output, or if you connect a battery to it?

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[tilmanb]

No, only of I connect a battery to the servo changer do I get a light.
And surprisingly when I power the receiver up with no transmitter. As son add the signal is there the led go off.

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[Kilrah]

Ok, can't help you then. I've used the sbus for my naza without issues, but never tried the converter yet.

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[tilmanb]

Did you have to set anything yo to get the right channels?
In assuming right now that channel 1-8 are on sbus and the pwm pins.

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[Kilrah]

Yep that should be it.

Are you in D16 mode?

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[Bill]

The default outputs for the s-bus are channels 9 and above, mirror your channels 1-8 on channels 9-16.
You should then have no problem.
Here's a useful link :
http://www.rcgroups.com/forums/showthre ... 834&page=8
The manual with different binding options:
http://www.google.co.uk/url?sa=t&rct=j& ... 2k&cad=rja
You could bind it in mode 4 jumper CH1 and CH2, CH3 and CH4.
But if you bind it with no jumper channels 9-16 should appear on the s-bus which sounds as though that's what's happening so mirror the output 1-8 channels and they should appear.

[Kilrah]

Sbus always carries all (16) channels. You then configure the decoder to output those you want.

I asked about D16 because while the X8R can be bound in D8 mode it is only meant for backwards compatibility, and makes little sense when the radio is the Taranis. I have not checked if sbus output was active when in D8 mode, it might not be.

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[tilmanb]

I kind of got it figured out.

There is definitely some kind of bug or unexpected side effect with the amount of channels sent. Perhaps a logic or timing issue.
The problem is probably in either the receiver or the transmitter.

You should be able to reproduce. Create a four channel model and you will see none of the channels get carried on SBUS (Or at least the SBUS decoder has no clue)
Then add a mix on channel 8. And suddenly the decoder springs into life!

It seems a bit random. I don't fully understand yet. But it seems also somehow to relate to the number of channels transmitted (Option in D16 mode). I reduced it once and again suddenly I got a signal.

It seems reliable once it's working. But I would feel better if I would know what the issue is.
Needless to say, someone has to fix something here. I just don't know if it is the receiver or decoder firmware. Or the TX.

[Kilrah]

OK, so more details please

Create a four channel model and you will see none of the channels get carried on SBUS (Or at least the SBUS decoder has no clue)

With what module settings?
So here you only add something to the mixer, you don't change the module settings?

But it seems also somehow to relate to the number of channels transmitted (Option in D16 mode). I reduced it once and again suddenly I got a signal.

Reduced from what to what? No change in the mixer?

The only thing that could theoretically change something is the choice of transmitted channels in the module settings, when it goes from <=8 to >8.

[tilmanb]

OK, so more details please

Create a four channel model and you will see none of the channels get carried on SBUS (Or at least the SBUS decoder has no clue)

With what module settings?
So here you only add something to the mixer, you don't change the module settings?

Yes. Only mixer added.
Module settings are default D16 and channel 1-8.

But it seems also somehow to relate to the number of channels transmitted (Option in D16 mode). I reduced it once and again suddenly I got a signal.

Reduced from what to what? No change in the mixer?

The only thing that could theoretically change something is the choice of transmitted channels in the module settings, when it goes from <=8 to >8.

This test was not done under terribly controlled conditions. I just noticed it.
I think I had mixes up to channel 6 or 7. Then reduced the channels by one from 8 to 7.


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[tilmanb]

Should I report this to FrSky directly? I assume it is a issue with either the receiver or decoder.

[gangan34]

I have the same problem.The led light up when setting the channels using the channel changer.When the decoder is connected to the receiver,no leds light up and no servos move.the Taranis is set to channels 1-16 and the SBUS decoder has been set to channels 9-12. HELP,please

[Rob Thomson]

Should I report this to FrSky directly? I assume it is a issue with either the receiver or decoder.

I have passed thread info on to Eva.

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[Tomkfly]

I had/have a similar problem. When I got my decoders they worked (ch 9 - ch16). I upgraded to the latest firmware and set up a new model. Sbus wouldn't work. I checked the previous ones and they still worked. I tried to compare them and couldn't see any difference with the settings, so I copied one, renamed it and modified the mixes. That works, but now I have a problem with the Companion sim. I have moved Throttle to Ch1 and setup ch 2 as a ignition kill switch.when I operate the kill switch it takes the throttle to -100, but works correctly with the transmitter. Some of the other channels have similar problems.

Tom

[Tomkfly]

Just tried mine again and it had stopped working. Selected an old model and it worked. Reselected the new model and it was working again.switched Tx and Rx of and on and it wasn't working.
Repeated the above a number of times and the Same happens every time.

Tom

[Kilrah]

Can you post your eeprom file? And mention which model works and which doesn't?

When sbus doesn't work, do the normal servo outputs work?

[Tomkfly]

Can you post your eeprom file? And mention which model works and which doesn't?

When sbus doesn't work, do the normal servo outputs work?

I'll have a go at posting the EPROM and I haven't checked the normal outputs, but I will shortly and let you know what happens.

Tom

[Kilrah]

My guess is you have the receiver number wrong on the new model, thus the reciever not responding at all and requiring a rebind (or manually setting the receiver number to the same value as the model it was previously bound to). This is a safety feature so that a receiver does not respond if the wrong model is selected on the radio.
Maybe check that.

[Tomkfly]

My guess is you have the receiver number wrong on the new model, thus the reciever not responding at all and requiring a rebind (or manually setting the receiver number to the same value as the model it was previously bound to). This is a safety feature so that a receiver does not respond if the wrong model is selected on the radio.
Maybe check that.

i dont think that is the problem. one of the first things I did, when I found I had a problem, was rebind the receiver. I have just rebound it to a different number and it still wont work.
I also checked to see if the normal outlets work, when there is a problem, and they do.
In my original post on this subject I said the mix for the kill switch was effecting the throttle in the sim but not the TX. I have discovered that is wrong, the Tx is also effected.

Tom

[Tomkfly]

document2.eepe

(77.03 KiB) Downloaded 204 times

eepe attached. I Hope
Model #2 YAK 52 TD is the one I'm having problems with. The model # around 56 to 60 - P51Ds are okay. Unfortunately, when I thought I had it sorted I deleted the original YAK.(Model # 1) setup. the current Yak was copied from a P51 setup and roughly modified, so needs some more work on it. I have only tried to get the First 3 CH working. CH 1 is Throttle CH 2 is ign/kill switch and CH3 is choke. The kill switch is SG is also affecting throttle even though it is not linked anywhere that I can see.
what i am trying to do is have all the functions in the wing on Sbus and the fuselage functions in the RX.
I did try with wrong Rx # just to see what happened. nothing would work and one green light illuminated in the Sbus decoder.

Tom

[Kilrah]

Please give your entire raw eeprom out of the radio like I asked. The goal is to compare the working models to the non-working ones and see if something obvious explains it.

[Tomkfly]

Sorry I thought that was what you wanted.
I'm having a problem attaching the EEPROM. When I get the file from the Tx I end up with a ".bin" extension and when I try to attach it the forum says "bin files not allowed". Is that the wrong file or do I need to zip it?
I have zipped it and attached hoping it is what you need.

Tom

EEPROM from TX.zip

(2.64 KiB) Downloaded 165 times

[Kilrah]

Zip is fine.
Now which are the models that work and those that don't?

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[Tomkfly]

document2.eepe

eepe attached. I Hope
Model #2 YAK 52 TD is the one I'm having problems with. The modelS # around 56 to 60 - P51Ds are okay. Unfortunately, when I thought I had it sorted I deleted the original YAK.(Model # 1) setup. the current Yak was copied from a P51 setup and roughly modified, so needs some more work on it. I have only tried to get the First 3 CH working. CH 1 is Throttle CH 2 is ign/kill switch and CH3 is choke. The kill switch is SG is also affecting throttle even though it is not linked anywhere that I can see.
what i am trying to do is have all the functions in the wing on Sbus and the fuselage functions in the RX.
I did try with wrong Rx # just to see what happened. nothing would work and one green light illuminated in the Sbus decoder.

Tom

Sorry!
you may have missed the above, because I edited it after you read the post.
So Yak has the problem and the P51s are OK.

I have now moved THROTTLE back to Ch 1 and KILL SWITCH to Ch1 and there is now no interaction between them. However I now have the problem with USB not recognising the TX again, so I can't flash it at the moment. I will have to get on to my Daughters Mac.

Tom