Modify Turnigy 9x to prepare for Firmware upgrade

[Hugh Hemington]

The Open 9x crowd has improved firmware for the Turnigy 9x and all other variants of this radio. That includes the FlySky, Eurgle and a few others.
Their main Wiki page is: http://openrcforums.com/wiki/index.php/Main_Page
The forum index is here: http://openrcforums.com/forum/index.php

With the Turnigy 9x you basically have two choices for upgrading the firmware. You can buy a SmartieParts board that presses against the correct six spots on the main board (you hope), and that puts the "USBasp" (or programmer) inside your radio where you connect to your computer via micro-USB. http://www.smartieparts.com/shop/index.php?main_page=product_info&cPath=3&products_id=331
Or you can buy a USBasp and extend the correct contacts out of the radio with a cable, soldering to the correct spots. I chose the second option.

The "instructions" (Step 2 on the wiki) are about what we've all come to expect. A guy who can't solder did three videos, where one would have sufficed, and didn't really cover very much. But in the video, he did divulge two critical pieces of information:
Where on the board you solder the wires/signals. And what pins do what on the standard USBasp.

The video showed someone soldering both ends of ribbon cable. You probably know that ribbon cable does not solder well, because the jacket is not heat resistant (because it's RIBBON CABLE!). He didn't, and had some difficulty.
I opted to use a PS/2 keyboard extension cable I had lying around. Since this solution calls for six conductors, this cable works well. The wires are colored. You know they are straight through, and they stand up to soldering better than ribbon cable. While I may be able to push most of the wire back inside the radio, I wouldn't want it to foul the gimbals, and I don't really care if the end of the PS/2 cable sticks out the hole I ground into the side with my dremel tool. If you attempt this mod on your Turnigy, I highly recommend you sacrifice an old PS/2 extension cable on the alter of better firmware. Having colored wires is much easier than only one colored wire and the rest gray.

My USBasp is on order from here: http://9xrprogrammer.com/index.php/shop/35-programming-6-pin
Although I got the $9 one! (splurged) When it arrives, I'll have to adapt/solder the six wires at the end of the cable to the correct six wires on the ribbon cable. Or I'll solder the wires directly to the PCB and use the male/female connectors of the PS/2 cable to connect to my radio whenever I want to flash the firmware again.

 

[Hugh Hemington]

Well, that was FUN! I got the backlight kit installed, the + & - buttons switched and the firmware wires terminated to a plug and on the next closed-case test, the MENU button no longer did anything. The EXIT button produced the menu on a long press. I can feel the momentary switch actuating, so I know it's not a mis-aligned button pin.
I opened it up and saw that the solder pad for Sync-Clock, between the processor and a resistor had torn off the board. I had not counted on the pads being attached with fly spit. I tagged a thin wire on the SMD chip, and another on the resistor as best I could, then joined them with the SCK lead of the flash harness and tried again... NOPE! MENU button is crap. So basically, the radio is crap.

Now I'm thinking FrSky Taranis. Maybe I can re-use the new 3S lipo I got for the Turnigy in a Taranis? Now I have a USBasp, but it was $9; no big deal. Another $5 for the backlight kit, but I may find a use for that at some point, considering it's just a wide-voltage flat light.

MOVING ON! I also got my 3S flight and FPV lipos today, and indeed with a 3S, the motors don't get nearly as hot, so I think I may be flying with that (once I get a radio). The FPV is awesome. I did a ground test and walked several blocks, still getting a great picture ON THE GROUND.

My Astak demonstrated a strange issue though! While you can flip the image on the screen on the back, and probably what gets recorded, it does not flip the realtime analog video output. That stays upside down. So I have to figure out how to mount the camera right way up, or get a separate FPV camera.

About the only thing left to happen is to find termites in the wood frame!

 

[Mike]

I used the smartieparts board on a 9x, which was easy and worked great (although costly, especially when you add shipping)- but the throttle gimbal on the 9x didn't make great contact anymore after a few flights, and HK doesn't sell replacements, so it was kind of a waste in the end to even modify that tx.

The 9xr has a built in AVR header and they sell replacement gimbals, so I don't even know why they still sell the 9x =) The prices are pretty close, and even though the 9xr doesn't come with a module, if you buy the 9x, you should throw the stock module away anyway and replace it with a frsky or something.

 

[Hugh Hemington]

The best thing about the 9x is that you don't lose much when you dump it. Even with the back light the low-res screen is hard for me to read, and without PC config software, setting up models is a chore. I'm not shedding any tears -- I know I'll be a lot happier with the Taranis! The display on it has twice the resolution. If I meet anyone with a 9x, I'll have spare parts to give them.
I ordered the parts to add 4 channels to the FrSky X8R with a decoder. It still isn't clear to me how it does telemetry -- the receiver also transmits?

 

[Mike]

Exactly, I ripped my frsky out of it and threw it in a box. I wasn't sad, but after the backlight, frsky, smartieparts board, and all of the headaches, I could have spent the money on a nice DX6i or something.

What part of the telemetry don't you understand? For most of the data, you have to add their sensors to your copter. They are pretty cheap though.

 

[Hugh Hemington]

I have a telemetry radio as part of my ArduFlyer 2.5.2 "kit". It connects to the controller at the I2C port. So that will transmit telemetry back to a laptop at 915MHz.
The FrSky GPS "sensor" appears to BE a GPS (but they don't tell you if it's a NEO or LEA), but it doesn't feed my flight controller. Don't I want to know what the GPS that is actually contributing to flying my quad thinks reality is? (HobbyKing does not appear to sell the GPS sensor anyway, so maybe that's a clue. They don't sell the lipo sensor either) I see another "sensor" that seems like it extends telemetry out to what appears to be a wired USB interface, but there is absolutely no information about it! What a weird company! http://www.frsky-rc.com/product/pro.php?pro_id=38
And again, my power module is already measuring volts and current. I suppose it might be good to know what every cell is doing, but that may be too much detail while flying, and it appears you plug the balance plug into this sensor, although they don't actually say that.

This guy seems to be routing telemetry off his OSD through something that may be called a "Teensy" to the X8R.

I would think I could route the data out of my APM without the OSD in the path, since I'd just as soon keep my FPV view clean and hear telemetry data when thresholds are exceeded, or periodically at my command. I may not fly with a laptop and USB telemetry link all the time.

I think what I have not seen actually spelled out explicitly is that the X8R is transmitting back to the Taranis. It makes sense, if the radio can alert the user that the link is becoming weak, but they don't come out and say it anywhere that I can find. I see the X8R has two antenna leads, and I assume one of them is a transmitter antenna, but it seems peculiar that no precautions are communicated about keeping it away from other antennas, nor is there an apparent option to replace it with a circularly polarized antenna, or mount it very far from the receiving antenna (if the two antennas perform different functions).

I really like to understand how each part works, and at least the basic theory behind any protocol being used -- ACCST for example. I've spent some time trying to understand "Smart Port" and "S.BUS". It appears you can daisy chain devices on Smart Port (meaning it's a BUS) while S.BUS just plugs the receiver into one thing, so it's really more like a physical PORT (running a two-node serial encoded data bus, based on RS-485).

In most industries that sell products, it's hard to escape sales pitches, but in the RC hobby, the relative lack of information is almost creepy.

 

[Hugh Hemington]

After further investigation it seems SBUS (sometimes called S.BUS, other times S-BUS) is from Futaba and has become a sort of standard. It is a BUS, but the devices do not daisy chain -- they get assigned a channel first, then connected into Y-cables or "hubs" (which HobbyKing doesn't sell). The SBUS is ground-to-sky only, and designed to drive a compatible flight controller, conventional servos using an adapter, or SBUS programmable servos.
Smart Port is a FrSky adaptation. It is bidirectional (where SBUS is not), and is the only way the radio receives telemetry. Where SBUS is a "tree", Smart Port is daisy chained. This was difficult to determine because I found no pictures of Smart Port devices that showed both in and out headers, and the documentation does not make reference to it.