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Arthur P.

Hacking the I2C interface of Spektrum DX and AR ?

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...has anyone looked at hooking up an AR9000 to a circuit like this?

Yes, I looked at AJ's AR9000. Some of the channels overlap each other. I could get four channels to work with the converter out of 7 that I could test (I only have a DX7 and once bound to that the AR9000 would only send out PWM on 7 channels). I could not tell if I could get the other 2 channels to work or not because I could not get any signals for them. My hope was that I could at least get 6 of the 9 to work with the MK and you could then pull off the other 3 ch separately. Unfortunately, I could not validate that this would work that way. We would need someone to map out the channel sequence for the AR9000 (on all 9 channels) to see how many channels are simultaneously spit out.

Richard

Edited by brashley

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We would need someone to map out the channel sequence for the AR9000 (on all 9 channels) to see how many channels are simultaneously spit out.

Didn't someone like Old Man Mike publish those details on the big MK thread at rcgroups.com?

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[quote name='brashley' date='Nov 29 2008, 12:42 PM' post='21449'

I am not sure what you were measuring...

sorry I was refering to changing the polarity when I hook it to the DMM changing the polarity changed the reading I got. I was reading about foreward bias etc when checking the led.... believe me though... I am just flyin by the seat of my pants here ;-)

This may sound funny but if you don’t have a scope I would say just hook it up. Well, you could double check for any shorts with your DMM (especially between power and gnd) and then hook up power and make sure all power is correct to all ICs. Then at that point you need to just wire it up for the AR7000 and get your MK going so you can then hook it up to the MK and see if the MK is seeing all the channels in MK-Tools. If you have a friend with a scope, you would still need to hook up the AR7000 but you could then look at the PPM signal and see if all was OK. If not we would have to work are selves back into what the problem is.

Edited by saabguyspg

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I was reading about foreward bias etc when checking the led.

Like many components, the LED would need to be checked before it was installed. Once in the circuit, the readings can be misleading.

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ok so I have the MK wiring harness ready to go... except for in the wiki the board they are using is different than mine so I can't hook up my + and - to the brushless controllers just yet....

but looking at the PPM converter there is a + and - on the board and there is the + - for the ppm signal

here is my assumption please tell me if I am correct

The ppm stream goes from the ppm converter board to the mk ppm connection and so does the + and - ..... so I assume that this provides power from the mk board to the converter board?

Then the larger pads that are + and - labeled on the converter board get connected to the recevier to power the receiver?

Then I just need the signal from each channel connected to the board.... do I need to connect the negative as well off each channel?

One last thing if I am going to run a bec (I plan to in the future) then do I assume I don't need to hook the large + and - pads on the converter board to the receiver....

oh yes and I am sorry about the LED I did install it then check it and after doing so... duh... realised that would be silly so I have false readings for sure.... newbie.

Really if someone had a picture they could post of one wired up that would be sooo helpfull to me...

Thanks all!

Edited by saabguyspg

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You dont need to have any of the brushless controllers hooked up to get the Flt-Ctr working. I would actually advise against it, make sure everything is ok before you start hooking up ESC and motors.

Yes, power needs to go from the MK to the Converter then to the Receiver and No you don’t need gnd for each channel (they all use the same gnd) I used one sdt servo connection (signal, +5, gnd) and hooked it up to RUDD on the receiver (this is the one that goes to the last channel on the converter (7 on P1). This is the only channel whose position is critical. All the other channels I just used single connectors on the signal pin.

The BEC is another mess. You need to be careful when you start mixing different 5v sources together which is what you would be doing if you ran the receiver from a BEC and the converter from the MK 5v vreg. I just pulled the 7805 off the MK and wired in a DE SportBEC and run everything off of that.

Richard

Edited by brashley

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ok lucky me then as I have just tested the MK with brushless controllers and I have green lights on all of them as well as some nice morse code bleeping at me. I belive this is a good sign but the lack of english instruction is really becoming difficult at this point....

ie. for the FC there is an interface to the usb connection but no indiacation as to polarity one end to the other... well at least not that i have found as of yet....

it would sure be helpfull if someone wrote a proper how to manual.. but then I guess everyone and their dog would be flying them... I am barely out of the everyone and their dog category apparently ;-)

ok from this I can go ahead and hook some of it up.

so you hooked the +5 volt to the large pad on the ppm converter the ground to the pad beside and the signal to rudder. This powers the receiver.

All other signal wires hooked up in any order you wish cause I assume in the MK tool you can order them.

Then I see in the schematic there is a bridge if the ppm converter is to be used on the ar7000... try as I may I don't know where that bridge is...

again I really appreciate your guys' patience and hopefully these questions will help someone else as dumb as me hook this up one day.

as far as the bec goes, can I not power the receiver off the bec, which would power the ppm converter then only one wire from the ppm converter to the fc board for the ppm signal? this way I can use my receiver to run the heavy load channel for lights but use the board to power the tilt servo so that I can utilize the stabilization?

You dont need to have any of the brushless controllers hooked up to get the Flt-Ctr working. I would actually advise against it, make sure everything is ok before you start hooking up ESC and motors.

Yes, power needs to go from the MK to the Converter then to the Receiver and No you don’t need gnd for each channel (they all use the same gnd) I used one sdt servo connection (signal, +5, gnd) and hooked it up to RUDD on the receiver (this is the one that goes to the last channel on the converter (7 on P1). This is the only channel whose position is critical. All the other channels I just used single connectors on the signal pin.

The BEC is another mess. You need to be careful when you start mixing different 5v sources together which is what you would be doing if you ran the receiver from a BEC and the converter from the MK 5v vreg. I just pulled the 7805 off the MK and wired in a DE SportBEC and run everything off of that.

Richard

Edited by saabguyspg

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ok so I put 5v from the receiver to the ppm converter and I get three quick flashes of the led then the led goes on solid..

I have to assume this is a good sign!!! no puffs of smoke...

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yippeee skippeee... ok so I have it all sorted now... the led on the ppm converter goes out (like it is supposed to do) I did not have the jumper soldered... done and the red light is out on the fc board! sucess it is getting ppm....

thanks guys, sorry for the questions but like I say hope it helps someone else.

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Congratulations on the successful build.

There are instructions buried in this long thread on how to setup the throttle channel to trigger the PPM failsafe upon loss of R/C signal. As you have observed, the LED goes on during the failsafe state, otherwise it is off when all is good.

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Good Job!! RED LED on FltCtr going off is a good sign but you will need to make sure you have all 7 channels in MK-Tools. No USB on the FltCtr (from your note in other thread) it is all serial. You either need a serial port or some USB to serial port converter in order to get things working with MK-Tools. The Channel configuration tab in MK-Tools will be your proof that all is well .You should be able to see all 7 channels move and you should be able to setup each channel so that the throws and centering all work correctly. I think I have some notes earlier in this thread that give my DX7 setting per channel. Dont forget to make the channel selections/mapping for each param setting. Other wise when you switch thing will stop working and you may accedentally start the motors and have some bad things happen.

Richard

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Thanks Brashley!!! and thanks to Mr rc-cam for both your help. I know it's annoying helping us non electrical guys but we got her done!

The mk is hovering in a space about 8'x8' (very small but only broke one prop on my drill press so far) Thanks for the tip about assigning the parameters to all channels... I actually ended up with a close call because of something similar going wrong but it's all good now.

I am having trouble getting one of my channels to show up in the mk tools but for now I can live without it. I use a futaba 9zap with spektrum module so I had to do some creative testing ;-)

Anyway I guess I will sign off for now as the build on the ppm was a success.. oh I have to find out where and how to program the fail safe now.

cheers

Steve

Good Job!! RED LED on FltCtr going off is a good sign but you will need to make sure you have all 7 channels in MK-Tools. No USB on the FltCtr (from your note in other thread) it is all serial. You either need a serial port or some USB to serial port converter in order to get things working with MK-Tools. The Channel configuration tab in MK-Tools will be your proof that all is well .You should be able to see all 7 channels move and you should be able to setup each channel so that the throws and centering all work correctly. I think I have some notes earlier in this thread that give my DX7 setting per channel. Dont forget to make the channel selections/mapping for each param setting. Other wise when you switch thing will stop working and you may accedentally start the motors and have some bad things happen.

Richard

Edited by saabguyspg

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I guess I will sign off for now as the build on the ppm was a success.

Glad to hear you are in the air. Now you are in a good position to help out the next fellow that has questions while building the V3 board. So don't go away! ;)

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I will be here and waiting for newbie questions that I can relate to......

Glad to hear you are in the air. Now you are in a good position to help out the next fellow that has questions while building the V3 board. So don't go away! ;)

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Hello folks,

i think about the Failsave Functions from PWM2PPM Version2 and Version3 with the extra Fail Save PIC.

Isn't it like this that you can Setup your RX with a Fail Save Values?

And why you dont do it then like this:

GPS Function Channel set to Coming Home

throttle to 40 or 50% (the same like you can Setup at the MK Fligth ctrl Board)

I think this procedure has some advantages then PWM2PPM Version3 where you try to give the Fail Save Controll to the FC Board....

ok this only a question from MK fligth ctrl Firmware, but there you could at moment not setup the homing function at fail save situation.

I am right with this reflection, or i have oversight some part?

Cheers

Christian

Edited by ufo4aliens

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Isn't it like this that you can Setup your RX with a Fail Save Values?

And why you dont do it then like this:

GPS Function Channel set to Coming Home

throttle to 40 or 50% (the same like you can Setup at the MK Fligth ctrl Board)

Hi Christain.

One of the problems is that the only channel that can be “programmed” with a failsafe position is the throttle; all other channels stay the same. So you could remove the PIC and set the throttle to say ~40% (something that has the MK descend slowly). That would certainly work. The motors would never go off though if the signal was never reconnected. At least with the PIC the FltCtr allows you to set the ‘On’ time of the motors and the FltCtr also goes into a very stable flying mode (just level with modified parameters). If you use the AR7000 only with throttle failsafe then all channels but the throttle are held at the last position so if you were moving away (tilted) you would continue to fly away with motors never stopping until the battery is burned up. With a simple code change in the FltCtr you could activate the ComeHome function on PPM signal loss (who knows, they may add something like this in the future). The PIC solution would allow you to take advantage of that. It is your preference….

Richard

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Thanks Brashley, I did not know the Fail Save Function from Spectrum, i thought it is like JR PCM Receivers, where i can store each Channel for his Fail Save Pos.

By this way is the PIC Version much better and make sense...

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Hi and a happy new year to all!

I have just completed my build of the PPM converter and intend to use it with an AR6100 and my DX7. While I have looked carefully through the posts and I think I have covered all the bases as far as getting the SMD build right, I am not sure that I have all the connections correct. So I have prepared a pictorial schematic in the hope that one of you out there can validate the wiring.

I have tested the PPM board and the LED first blinks then remains on. I have checked that I am getting signal into the board but would like to know where are the best test points to use on the PWB to confirm the existence of the PWM signal.

So in conclusion could anyone please help with the following:

1. The cct diag. (post 220) shows a jumper accross JP11-Throttle (What do I need to short accross? What is JP1? Is this a mistake?)

2. Should the PPM converter board LED reamin on after the initial blinking??

3. Can anyone please help with an explanation of what should appear at the test points on the PWB?

4. Could someone please validate the wiring shown on the attached picture.

I am compiling all the material I have used to build the MK in to a project manual for other newbies like myself so all input is welcome. thanks :)

post-4929-1231368796_thumb.jpg

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1. The cct diag. (post 220) shows a jumper accross JP11-Throttle (What do I need to short accross?

On the bottom side of the board (side with LED) there is a double row of pads near the servo I/O connections. You need to jump the pad set that your throttle channel is connected to. With the throttle channel applied as you show, you would jumper the pads in the photo below (these two pads are JP1):

post-2-1231370899_thumb.jpg

This long row of double pads is essentially a hardwire programming jumper area that determines the servo channel that will be used for sensing the Rx's failsafe servo source (use throttle channel on the AR7000). If the failsafe PIC is not installed then this jumper is not needed (jump U3-1 to U3-5 instead).

4. Could someone please validate the wiring shown on the attached picture.

The MK connections are incorrect. In your photo, it shows the MK wired to the auxiliary power pads (these pads are an unadvertised free bonus that can be used to daisy chain power to another place, or to obtain power from the R/C Rx). Although three pads are provided, only the pads labeled + and - are used. The third unlabeled pad is just a place to park (solder) the unused conductor on 3-wire servo cable for a more tidy looking installation.

The MK connects to the J1 pads below the auxiliary power pads. If the MK supplies 3.3V or 5V power, then you would connect - (common Ground), + (Power), and P (positive PPM out). If power is from the R/C Rx, then omit J1's + connection. The pad labeled N is inverted PPM logic (Negative PPM out), for host boards that need such a thing.

What is JP1? Is this a mistake?

See response to [1], above.

Should the PPM converter board LED remain on after the initial blinking??

It will be on during the Failsafe state. Once you correct the wiring it should turn off to indicate that failsafe is not being detected (normal operation). Once you determine the board works with the MK, you would use the instructions provided earlier in this thread by brashley to setup the Tx for throttle based failsafe detection. Then you will be good to go!

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Thanks for the speedy reply Mr. RC-Cam!! I think I understand now.

With the throttle channel applied as you show, you would jumper the pads in the photo below (these two pads are JP1):

The attached pic now shows the corrected connections (I hope). JP 1 is jumpered for the throttle ch.

The MK connects to the J1 pads below the auxiliary power pads. If the MK supplies 3.3V or 5V power, then you would connect - (common Ground), + (Power), and P (positive PPM out). If power is from the R/C Rx, then omit J1's + connection. The pad labeled N is inverted PPM logic (Negative PPM out), for host boards that need such a thing.

Could you please confirm that I have connected to the correct pads as shown in the pic?

If the attached diag shown ther correct connections then I will clean it up and save it for inclusion the build manual.

I will find brashley's instructions and get on with the next phase.

Thank you. :)

post-4929-1231380389_thumb.jpg

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The new wiring looks fine to me, except for the P1-7 input (see below).

FWIW, your AR6100 power is shown sharing the J1 + and - pads with the MK wiring. It might be better to show the dotted lines (from the AR6100) going to the auxiliary power solder pads (these are now empty after moving the MK cable to J1). These two soldering pad areas are electrically the same between the + and - pad locations (if in doubt, your ohmmeter will confirm that).

One important thing is that the very last servo pulse in the Rx's PPM stream must go to P1-7. This servo pulse position can vary on the various Spektrum systems. Assuming the AR6100 is the same as the AR6000, then you would connect P1-7 to the Rx's Aux channel. On the AR7000, P1-7 would go to the rudder channel. Long story short, if you end up missing some servo channels while in the MK setup software then that would hint that the P1-7 is not correctly connected to the logical "last" servo channel.

Edited by Mr.RC-Cam

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Great News!!! Thanks for that.

The AR6100 power is shown sharing the J1 + and - pads with the MK wiring. It might be better to show the dotted lines (from the AR6100) going to the auxiliary power solder pads (these are now empty after moving the MK cable to J1). These two soldering pad areas are electrically the same between the + and - pad locations (if in doubt, your ohmmeter will confirm that).

I will change the + & - wiring for the 6100 to the auxiliary pads as advised.

The wiring that connects your AR6100 to the PPM board is shown with two of the channels out of order. This is fine since the V3 board does not care. To make it more logical, you can put then back in order if you wish. The only requirement is that the failsafe channel input must have its jumper installed (ref: JP1 in your example since throttle is the failsafe command channel on a AR6000, AR6100, or AR7000). Also, the CH8 input is not available by default, so avoid it.

Does this mean:

Aux - 6

Gear - 5

Rud - 4

Ele - 3

Aile - 2

Thr - 1 (jumper applied here)

Will look at changing the header end-pins to a 6 pin end-receptacle, sounds like a great idea.

Can you tell me where I should check with an scilloscope for the processed ppm? The diag says J1-3...I must be missing the board ref as i cannot find this.

Will report after the next test. Thank you :)

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Does this mean:

Aux - 6

Gear - 5

Rud - 4

Ele - 3

Aile - 2

Thr - 1 (jumper applied here)

In the grand scheme, the servo channel order does not matter as long as you [1] correctly jump the board's failsafe channel (throttle in your case, ref JP1) and [2] have the servo channel with the logic "end-pulse" connected to P1-7.

I am reluctant to say which channel on your AR6100 would go to P1-7. As mentioned, I suspect it would be the Aux channel. But that is just a guess since I only know the details to the AR6000 and the AR7000. It is hard to second guess the boys at Spektrum.

Can you tell me where I should check with an oscilloscope for the processed ppm?

It is found on the P (positive PPM out) and the N (negative PPM out) pads.

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I am reluctant to say which channel on your AR6100 would go to P1-7. As mentioned, I suspect it would be the Aux channel. But that is just a guess since I only know the details to the AR6000 and the AR7000. It is hard to second guess the boys at Spektrum.

I dont have a AR6100 either so I cant validate what channel should go to P1-7. It looks like this is a DF and not an MK. I think the best bet is to go with the the first guess to start with, then if channels are missing (as RC-Cam indicated) then move each channel one by one to P1-7 (all other channels must be plugged in to the other P1 spots) until you have all channesl show up. (or use a scope if you have one and look at the timing) I dont know how you check channels on a DF.

Richard

EDIT: I do have a AR6100.....I will try to hook it up to the scope and see what is going one from a timing point of view. It will probably have to be tomorrow evening though.

Edited by brashley

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I dont have a AR6100 either so I cant validate what channel should go to P1-7. It looks like this is a DF and not an MK. I think the best bet is to go with the the first guess to start with, then if channels are missing (as RC-Cam indicated) then move each channel one by one to P1-7 (all other channels must be plugged in to the other P1 spots) until you have all channesl show up. (or use a scope if you have one and look at the timing) I dont know how you check channels on a DF.

Richard

EDIT: I do have a AR6100.....I will try to hook it up to the scope and see what is going one from a timing point of view. It will probably have to be tomorrow evening though.

Thanks for confirming the 6100 connections to P1-7 Brashley. Much appreciated. :)

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