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Old Dec 09, 2012, 03:08 PM
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I have this working however, I am unable to set the right PPM order. Any suggestions?
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Old Dec 09, 2012, 03:24 PM
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Originally Posted by rimshotcopter View Post
I have this working however, I am unable to set the right PPM order. Any suggestions?
I don't think it's possible with this converter since it just repeats the channels as the Rx outputs them. Is it possible to change the PPM ordering in your FC?
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Old Dec 09, 2012, 03:31 PM
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I don't think it's possible with this converter since it just repeats the channels as the Rx outputs them. Is it possible to change the PPM ordering in your FC?
I am trying to do that now. I also tried moving the pins around on the RX and that did not work.
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Old Dec 09, 2012, 03:41 PM
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Worked it out with the following patch to the MWC RX.ino file and this PPM order.

http://www.multiwii.com/forum/viewto...M+order#p27568

Code:
#define SERIAL_SUM_PPM POLL,THROTTLE,PITCH,YAW,AUX1,AUX2,AUX3,AUX4
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Old Dec 09, 2012, 03:42 PM
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If you are using the KK2, be careful since some versions of the firmware the CPPM editor is wrong! Two of the labels are reversed.
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Old Dec 09, 2012, 03:51 PM
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Thank you Brontide.
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Old Dec 09, 2012, 04:24 PM
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With the std Turnigy 9x v2 radios, it seems that some of the v2 6ch rx's have ppm sum on bat port.
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Old Dec 09, 2012, 04:30 PM
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With the std Turnigy 9x v2 radios, it seems that some of the v2 6ch rx's have ppm sum on bat port.
They SURE DID, but I purchased three recently and they no longer have the PPM on the Battery. WTH!!!
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Old Dec 09, 2012, 07:13 PM
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Progress lol.

I need to check mine, must have 5 or 6 of the 6 ch rx's that I've had for a year or more. Might come in very handy for a project.

With your PPM converter did you manage a way to implement a failsafe?
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Old Dec 09, 2012, 07:17 PM
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Progress lol.

I need to check mine, must have 5 or 6 of the 6 ch rx's that I've had for a year or more. Might come in very handy for a project.

With your PPM converter did you manage a way to implement a failsafe?
Preliminary testing shows the signal stops outputting and the throttle goes to 1ms. For my copters, this is fair enough for testing however, I would love to get a better failsafe working. In fact, I am looking over the code at present, trying to gain a better understanding of how it works.

Very clever program I have to say.

It just came to me, to get the WMC's failsafe to kick in, all that is required is to turn off pin 7. That should be fairly easy to do if there is no signal from X amount of time.
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Old Dec 19, 2012, 10:04 AM
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Please forgive my OLD oscilloscope here.

Here is the problem that I am having, the attached photos show the PPM output using the current unmodified firmware. When the transmitter is turned off, there is still a PPM stream and because of this, the MWC failsafe will not engage. The RX is a Turnigy 9xBC version 2.
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Old Dec 19, 2012, 02:23 PM
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Found the freaking problem, on the Turnigy 9xBC version 2, when the RX looses signal, Channels Four and Channels five STILL output a signal. 1400-1500 Channel 4 and 1000-1024 Channel 5.
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Old Dec 26, 2012, 05:12 PM
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What you describe is particular for 9X RF system, and is one of his main weakness, but the general behavior of ALL 2.4Ghz systems is to output something on ALL channels when Tx is off.
There are two cases:
- hold last command
- programmable positions = failsafe.
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Old Dec 26, 2012, 08:40 PM
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Yea, the 9XBC is really aggravating because unlike the Flysky 6 channel version(without the PPM on the battery pin), channels 4 and 5 still outputs upon signal lost where as the 6 channels shuts down completely. Makes it really easy for a PWM to PPM encoding. I am in the process of adding a Mask to the code now, just wish I understood more about Interrupts routines on the arduino. I have set this project aside for a moment and used one of the six channels RXs I have on-hand to get the VTOL flying. Will return to this later because I will need the additional channels.
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Old Sep 28, 2013, 08:05 PM
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used this for almost a year now with no problems.
really make use of all 8 channels on any atmeg328 based board instead of limiting yourself to 6 channels.
just got a neo6m, price is so low now compared to last year. I am combining the i2c_nav_gps program with my ppmsum program on a pro mini.

to answer some of the earlier questions, you can connect all 8 channels to the atmega328 (or pro mini) in any order. The software does not care about the pin position, it simply multiplex the pulse coming in from any of the 8 channels to the output pin. You only need to make sure the ppmsum definition on multiwii config.h matches your turnigy transmitter setting.
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