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This year up updated our 9x to the new ersky9x board. Before we update we used the training function not a lot but we did use it .

This week we tried to use the training function and we couldn't get it working. We was using our
normal Tx as a slave. It just would not work. So we started to trouble shooting it with a O'scope
The level going into the ersky9x was from .5 V to 2.7 V on the PPM signal. It looked like is was
loading down my PPM because when the cable unplug it came up to a 0 to 5V good signal. The output of the Slave has an 1K ohm resistor in series with the PPM .
The wave form at Q2 collector was only about 1V with a lot of noise. If the cable was removed that collector went to 5 volts With the cable plug in from the slave is was 0 to 1 volt.

It look like the biasing on Q2 was incorrect. We put a 10K ohm resistor across the Q2 base to emitter . Now the collector is a PPM signal the 3.3 volts to .2 volts.

Now when use the slave it now works.

We have not changed the slave tx on it circuits at all between the usage of the old to new board.

My Slave Tx board is a MicroStar 2000 . With an FrSky transmitter module.

Just some INFO that my help others.

Charles

Keep up the GOOD work. I love the new Board update. Can't wait until the SD card works.

What firmware? I tried the same yesterday on open9x and it did not work


Sent from my iPhone using Tapatalk

My board is a Rev. B1
By my O'scope it was the biasing of Q2 form my slave having a
small DC offset of .5 volts that made it not work.

Charles ,
I think the leakage current of D8 , might be causing a problem, as the temp goes up so does the leakage current
It was added to help protect the PC22 port pin input.

The 10k would load the diode down better , and the leakage current would not cause a voltage rise.

Maybe the input should be capacitively couplled , instead of the DC connection?

Your SD card does not work?

-Brent

Yes it sounds like the diode. Thanks

I haven't been keep up with the Forums like we should.

I take it the SD card now can be installed and save my planes on it .

Thanks we try it some time this weekend .

THANKS

They got the Board to act as a mass storage device , yesterday.....there still testing....

The audio part of the SD card is working , and you can map sound events to alarms , and switch settings

-Brent

SkyNorth wrote:They got the Board to act as a mass storage device , yesterday.....there still testing....

Just tried it. Works.. but a little buggy. (files delete / vanish etc). Give it a week and I am sure Bertrand will have it working 100%.

Now...

How do I make the trainer port work on my sky9x board?

Rob

Here is away of adding a 10K resistor to the existing parts.

The 1K series resistor in the PPM input is a good Idea.
-Brent

We are only able to write files up to 256k. Impossible to rename a file or format the SD. For the moment no idea why.
Bertrand.

SkyNorth wrote:Here is away of adding a 10K resistor to the existing parts.

The 1K series resistor in the PPM input is a good Idea.

Trainer_Mod.JPG

-Brent

So... adding the 10k resister sorts out the issue with the trainer not working?

Just clarifying before I solder to the board!

Rob

The 10K will load the Diode and should stop the diode leakage from causing the problem.

-Brent

we used a smt chip resistor and put it right on Q2 base and emitter .

Doesn't everyone have a 10K 602 part. LOL
It all most look like a factory part. LOL

Charles

WHAT!!
you mean sky9x board is worse than the stock board.
the stock board only need 1k resistor to make it work, the SKY9x need 10K. 10 times worse! Geesh!

Right. I think some clarification is required on this fix.

Have re-read the thread as a 'newcomer' looking for a solution - I do not see a clear way to solve the issue.

I believe the issue in question is that the trainer port is not working correctly on the sky9x board. Is this correct?

If this is the case. What is the step by step fix to solve the problem? In non technical terms. (i.e. a picture and part list with a suitable fix)

Rob

sounds like you are one of the new comers.

Lol... that was my point.

I did not see a clear solution to the problem. So need to get it spelt out so we can add it to the wiki

Sent from my Nexus 7 using Tapatalk 2

In general, I think the trainer input does actually work. I believe this is about a specific student input that didn't work. Yes, there is a resistor change that might improve things, but I'm not convinced everyone needs to do the change. If the input goes to 0V, then it all works fine. A resistor between the signal and 0V could be added in the cable.

Mike.

Reason I ask is that I cannot get my sky9x board to work on a sim, or as a buddy box


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That's a different problem, that's using the trainer port as an output, not an input. I assume you have open9x. Have you tried it with ersky9x? I'm pretty certain I have tested this functionality. The only 'feature' I know of is the trainer output is inverted compared to the signal to the TX module. This is because it uses the complemented hardware PWM signal from the processor.

Mike.

So... either I need to change the ppm from negative to positive... or test with sky9x to see if an open9x bug. Will do that tomorrow

Rob, I just plugged my ersky9x equipped radio into my sim adapter and it is working as expected. So I can confirm that ersky9x is working.

i have open 9x on sky9x board rev.B and everything seems to work fine here on the sim and on buddybox

I also have a slight issue with the input for my trainer port, movement of the servos is rougher when the student radio is in control than it is when the master is in control. I've tried a couple different radios as student and both have the same issue so I think it is actually my sky9x board causing the problem, however the control looks good enough to use still (I haven't actually tried it yet). When I'm using the trainer port for output it works fine unless the stock tx module is in, then there's no output.

Apologies,

I have looked -- gotten frustrated, confused, set it aside -- looked some more -- but I seem to have a block.

I'm FINALLY installing my Sky9x board that I bought in July. I had problems right off the bat that made me loose my nerve ... then I was unavailable for life for the past 12 weeks -- and now I'm back to getting this installed.

I'm using a FrSKY DJT -- DIN connector -- but I'm confused on the TX connections.

In this photo the wires from the DIN appear to be connected to the TX-RXD connection near the 2.5mm plug.
http://openrcforums.com/wiki/images/a/a ... ncoder.jpg

But in this photo -- they seem to lead elsewhere.
http://openrcforums.com/wiki/images/4/45/IMG_0531.JPG

Understand that I need .... never mind.. let's pretend like I don't understand a thing about connecting the module -- please give me a bit of help.

I think I have the rest of it figured out -- (crosses fingers).

It looks to me like they wrapped the frsky wire into the din wire for a tidy install.

Scott,

the first picture shows the two spare wires on the the 6 pin din/usb connector plugged into the Com1 telemetry port , this would bring the
connection to the Din connector for outside input - thru the 6 pin din.
In most cases you would connect the COM1 port directly to the DJT RX and TX output pins.

The second picture sort of shows this , but they have connected the RX and TX line to the two spare pins on the Back of the RF Module
Socket on the 9x (this type of mod requires that the Radio , and the DJT module be modified to do this.)

All you need for the Telemetry is 2 wires one going from the RXD pin on COM1 to the TX pin on the Back of the DJT RF module and the other
going from the TXD pin on COM1 to the RX pin on the back of the DJT module. You do not need the ground connection , as it is already
connected.

-Brent

SkyNorth wrote:Scott,

the first picture shows the two spare wires on the the 6 pin din/usb connector plugged into the Com1 telemetry port , this would bring the
connection to the Din connector for outside input - thru the 6 pin din.
In most cases you would connect the COM1 port directly to the DJT RX and TX output pins.

The second picture sort of shows this , but they have connected the RX and TX line to the two spare pins on the Back of the RF Module
Socket on the 9x (this type of mod requires that the Radio , and the DJT module be modified to do this.)

All you need for the Telemetry is 2 wires one going from the RXD pin on COM1 to the TX pin on the Back of the DJT RF module and the other
going from the TXD pin on COM1 to the RX pin on the back of the DJT module. You do not need the ground connection , as it is already
connected.

-Brent

Thanks Brent.

So those two pictures are not examples of what I need to accomplish - if I understand you correctly. I'm sure i'm making this harder than it is.

Here is what I have -- am I suppose to put the line from the USB.DIN to Com1 or Com2 .. I'm still not clear on what happens to that yellow and white line. Does this look correct and ready to put into place. (The display is not connected --- as I am doing that last to I don't damage it with the futzing around.)

SkyNorth wrote:Scott,

All you need for the Telemetry is 2 wires one going from the RXD pin on COM1 to the TX pin on the Back of the DJT RF module and the other
going from the TXD pin on COM1 to the RX pin on the back of the DJT module. You do not need the ground connection , as it is already
connected.

-Brent

Dang -- I think the light just went on. As usual I was expecting more work that is necessary. If I get it now -- there are three different ways to connect the sky9x board to the DJT for telemetry.
1. connect the yellow and white wires that are on the Din/USB setup to the Tx and Rx on the outside of the DJT.
2. connect the 2.5mm jack through a hole drilled in the transmitter and connect that to the DJT.
3. Connect directly from the Com 1 to the Tx and Rx on the outside of the DJT.

And if I am seeing in the light now -- any ONE of those combinations will enable the TX to handle the FrSky telemetry.

Yes , any of the ways you mention will work.

I think most people use a servo extension connector to plug into the back of the RF module.
The only thing to be careful about is the 3rd pin on the back of the DJT is +5V not ground as would be used by the RS232 connection.
But Ground is already connected through the main power , so you only need the two connections (RX and TX)
So you need to cut the wire going to the 5V pin. (or not connect it to the GND (ground) pin on the COM1 connector , as this
would short 5V output of the RF module to ground.

A small hole drilled in the back of the radio , allows you to fish the wire through to the module.

The key thing to remember is that a serial connection needs to be crossed over to be able to talk to each other....
That means that TXD (Transmit) on the Sky9x needs to connect to RXD (Receive) of the RF module and RXD of the Sky need to connect
to the TXD pin of the RF module.

The Wiki , has a lot more info on it these days ..do to some hard work from others...Thanks...
http://openrcforums.com/wiki/index.php/ ... rd_Upgrade

-Brent

SkyNorth wrote:Yes , any of the ways you mention will work.

I think most people use a servo extension connector to plug into the back of the RF module.
The only thing to be careful about is the 3rd pin on the back of the DJT is +5V not ground as would be used by the RS232 connection.
But Ground is already connected through the main power , so you only need the two connections (RX and TX)
So you need to cut the wire going to the 5V pin. (or not connect it to the GND (ground) pin on the COM1 connector , as this
would short 5V output of the RF module to ground.

A small hole drilled in the back of the radio , allows you to fish the wire through to the module.

The key thing to remember is that a serial connection needs to be crossed over to be able to talk to each other....
That means that TXD (Transmit) on the Sky9x needs to connect to RXD (Receive) of the RF module and RXD of the Sky need to connect
to the TXD pin of the RF module.

The Wiki , has a lot more info on it these days ..do to some hard work from others...Thanks...
http://openrcforums.com/wiki/index.php/ ... rd_Upgrade

-Brent

Thanks Brent,

I read the wiki many times -- what I didn't seem to understand was that there were so many options to hook up the DJT -- somehow I thought that I needed to use a combination of them. Obviously I'm not electronically gifted.

Last clarification -- confirmation before I button up this case and apply power to it. I have the option of simply coiling the yellow and white from the Din/USB and leaving it unattached to anything if I'm using the 2.5mm cable you sent me. (in the photos). -- correct?

And -- If I understand what you say about the third wire -- the ground -- that's in the 2.5mm cable I pictured above (that you sent me) -- I need to cut it for the DJT -- but presumably I would leave it for using a DHT-U. Does that sound correct?

BTW: i plan to contribute both to Wiki and sound files once I get this ironed out. I have access to many voices and a sound recording studio -- All I need is a list of commands to be read for that -- and I have a macro photo studio -- as I teach photography and broadcasting. Maybe I can finally contribute to this project rather than leeching all the time.