Turnigy TZ-85A brushed motor hack - amended code for Spektrum Dx6i

Hi all,

Following on from the amazingly brilliant open source code created by Aaron Knight and Steve Martin at Botbitz to convert Turnigy TZ85a ESCs from brushless to brushed motor controllers that a load of us have used, a few of us have experienced issues using this code relating to the Spektrum DX6i's internal mixing when measures are implemented to facilitate 100% throws in all directions as opposed to the stock elevon function that only allows 50% travel in the forward and backwards directions. This is due to this mixing set-up causing the RC signal to go above 100% which causes the hacked ESCs to failsafe. There have also been issues with the temperature limit kicking in too early and failsafeing robots as well.

With a massive amount of help and guidance from Kane, John from Team Beast and advice from Aaron and Steve on the robowars forums relating to the temperature limit problems, i've been able to adjust their open source code slightly to compensate for the DX6i's weird mixing and turn off the temperature limit. This code is attached below. Using the botbitz tutorial to install the code, both Team Beast and I have tested the code and it worked for us but if you intend to download, install and use it, this will be at your own risk and I take no responsibility for any damage caused by its implementation. I also cannot guarantee that this code will work for you either. Below are the two set-ups that its been tested on so far:

My set-up: DX6i, Orange Rx 620, two ESCs running four gimson 18v 24:1 gearmotors on 6s
Team Beast set-up: DX6i, Spektrum BR6000, two ESCs running two speed 900s on 6s

I would like to take this chance to really thank Kane, John, Aaron and Steve for all their help in solving this problem as its really been bugging me for a long time, and especially thank Aaron and Steve for creating the code in the first place. Below are some links relating to the TZ85a hack:

The original how to hack and program TZ85a tutorial by Aaron and Steve at Botbitz: http://robowars.org/forum/viewtopic.php?t=1609
How to hack video from Aaron and Steve at Botbitz: http://www.youtube.com/watch?v=EAKYSyOx75Q
How to program video from Aaron and Steve at Botbitz: http://www.youtube.com/watch?v=i1-bWNeuAqA
DX6i full servo throws video: http://www.youtube.com/watch?v=6Ewa79_9Iq4

Attachment 3801

Thanks for this. Looking forward to trying it out

Chris

Thanks for all YOUR effort Dan.

Programmed up 3 TZ85 with the new code.
This fixes the >100% mixing problem of the old code. Havent been able to do a test drive, just a bench run but this is going to make the bot alot more controllable. Thanks again

Did some more testing today and all worked well on my set-up!

I re-programmed my ESC's with this code and they worked really well.

I've used them in my uni project, here's some footage of it driving around.

http://www.youtube.com/watch?v=HOUYbgvVgAs

How easy is it to do a reprogram and what effect would it have on switching to other transmitters?

We have 6 TZ85A's and both run DX6i's but I was thinking that it would be easier to go up to a DX7 or drop down to a DX4 just to solve the issue permanently.

Could we post them to someone as well to have them reprogrammed?

Reprogramming them is easy. Just buy the pololu programmer, solder a few connections on the board, install software on your pc and then hit a button and it's done.

If I was to reprogram for you I'd want something for my time. TBH you'd be best learning to do it yourself as it's not difficult

It's really not that hard at all, can be a little daunting at first though. If your ESCs at the genuine botbitz ones, you'll need to solder a new wire to the B port as they will have removed that and the open source code uses it. Team beast had the same problem with a dx7 so buying a new spektrum Tx probably wouldn't work.

Thanks guys.

Yeah, they are Botbitz ones. It will just save us a ton in time and money if we can get it working as we can hack our own from scratch too.

just an update tried to blow it up today just wheels spins and does not stop its pretty cool now testing at Guilford on Sunday :)

ps itd an old dx6 not an I :) ok

I have stalled a drill out on them. You will struggle to blow one with a feather.

I've stalled a drill (with a second often on a dodgy gearbox) on them in almost every fight, they never even get warm.

don't worry with johnno and Alan driving they will get warm with speed 900s (better do or we are out lol)

A quick question to those that have reprogrammed these escs- I am looking at having to reprogram quite a lot of these controllers (possibly 20 for 10 robots), what I wondered was would it be fairly simple to make up a jig so I placed the controller on the jig which had littles wires poking out in the right positions to make contact with the reprogramming pins to save me having to do a load of soldering? Or does it need the extra wires to remain in place once reprogrammed?

Buy one of these:

http://www.hobbyking.com/hobbyking/s...dproduct=27195

It will make the process a whole lot easier.

Quote:

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Originally Posted by duff

Buy one of these:

http://www.hobbyking.com/hobbyking/s...dproduct=27195

It will make the process a whole lot easier.

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Has anyone hacked any using one of these?

That looks awesome! Not used one but I bet it would make the process easier

I bought one last week, haven't used it yet, but am going to try hacking some beetle and antweight controllers first. But Marto says it will work, so that's good enough for me.

Socket firmware flashing tool works perfect!!
Thanks for the amended code my DX6i (and TZ85A) works good now :)

Think I might have to get one of those. Saves lots of fiddly soldering

How easy is the hack watched bids etc, and not too bad with the iron. Need three esc for the new no toy,

Videos hate predictive text on phones :D

its very easy but can seem daunting at first. Take your time and follow the videos as you do it. make sure you have good quality solder too.

And don't remove the heatsink as the video says, it never sticks the same again and there's no need to do it.

And if I remember rightly, the last wire you solder (which is the ground wire or pin 6) is soldered to the ground wire on the RC input wire on the ESC. Don't do that, its very fiddly and a pain. Easier way to do is to get a RC wire like the link below, cut it so you have one end with the female plug and the other where you've cut it. Solder the ground wire pin 6 programmer wire to the black RC wire and simply plug in the ESCs RC input wire into the female end, making sure that the bare red and white wires where you've cut don't touch (so seal them with tape or something) and you've got the rc plugs round the right way.

http://upload.ecvv.com/upload/Produc...9710172010.jpg

Seems a bit convoluted, I got my ground wire soldered in seconds. Just stick a blob of fresh solder on it before you try and solder the wire on (Marto does this in the video).
Agreed on the whole heatsink thing, no point that I can see. No need to put it all back in its casing before programming either.

The longest/most frustrating part for me was installing Atmel Studio 6.1 and all its associated cr@p. Then once you've opened the program up and are ready to go, the procedure is different to what Marto does in the video. He was using an older version (AVR Studio 4) and the interface on 6.1 is dfifferent. But once you figure it out, it's straightforward. The Pololu website has some troubleshooting sections that helped work it out (if you're using their board) but if necessary I can make a video to go through it.

Jamie I think a full upto date video with that cord, or whatever it is would be great, im not bad at electronics but I am only a mechanical engineer after all, ps I also hate computers not just predictive texts :)

So looking at the link the new cable as in the link removes the cable soldering process, so does that just leave the switch wire link and output c removal , then just programming the esc. what is the programmer being used as there have been a few types used. sorry looking at the vids and links but just asking to clarify

will need to do some hacking very soon to run the speed 900s on there way

Sorry Adam, haven't got round to getting a video done. I've gone through the process and taken screenshots though so that might help.

Firstly, I'm using this programmer and cable: http://www.pololu.com/catalog/product/1300
Ordered it Friday morning, arrived from Vegas on Monday morning - can't argue with that!

I'm assuming that the cable you mention that removes the soldering process is this one: http://www.hobbyking.com/hobbyking/s...dproduct=27195
As far as I can tell, yes if you use this, all you need to do soldering-wise is the BEC switch link and the wire removal (although I just did the latter with a pair of wire cutters).

Right, using the Pololu programmer, make sure it's plugged into a USB socket (should install drivers automatically) and that it's connected to the ESC you want to program and that the ESC is powered up. Click to open Atmel Studio 6.1. Once that's loaded up, go to Tools and Add Target:

Attachment 4018

The following box will appear. The Pololu programmer isn't automatically detected by the program, so we've got to set it up. For Select Tool, STK500 was the only option available to me. In the Select Serial Port, you want to select which port the programmer is using. In my case, it was using COM6.(If you're not sure which port it's using, go to the Start Menu, open Devices and Printers, find the programmer and right click on it, select Properties, then Hardware and it should tell you there)

Attachment 4019

Once you've selected those two and clicked Apply, go back to Tools and select Device Programming:

Attachment 4020

This will again open up a window. On the top left hand side, we have to select the tool we're using to program the ESC, so click the drop-down Tool menu and select the option you've just set up (so, in this case, STK500 COM6):

Attachment 4021

Then we have to select the specific device name. There are a lot of options in the drop-down menu and I didn't know what mine was, but after doing some searching on the Pololu website FAQs and Information, I found out it was an ATmega8A:

Attachment 4022

Then make sure the Interface tab is set to ISP and click Apply. This is what you will then see:

Attachment 4023

You shouldn't need to worry about the ISP clock stuff. Where it says Device Signature, click Read and it should match up to the programmer you've got plugged in. Your ESCs need to have power for this bit to work. Then click on Memories on the left-hand side menu, and you'll see this:

Attachment 4024

All you need to do now is search for the .hex file that contains the new firmware (BrushedESCdx6iorangerx.hex.zip). Under the Flash (8KB) heading, you can see where I've got it saved. To browse for it on your computer, just click the small grey box to the right-hand side with the [...] in it and find where you saved it on your computer.

Then hit Program, and a few seconds later, that should be it done!

Like I said, this is only the way I've done it using the Pololu programmer. I have no idea how different it will be (if at all) when using the socket tool that doesn't require soldering. If the worst comes to the worst and you can't get them programmed, stick them in a jiffy bag and I'll do them for you if there aren't any local roboteers that can do it.

thanks for info Jamie will get on the case

2 x tz85 and programmer cable on there way, 1 pololu programmer also

Did you manage to have a crack at programming your ESCs Adam? If so, how'd it go? I have a feeling we might've talked about it at Wales but my memory's terrible.

And apologies in general for the thread bump, but any chance this can be made a Sticky thread please? The stuff in the first post in particular is pretty useful but I always forget where this thread is when I need to look it up and it gradually works its way down the topic pages.

Not yet all waiting on my desk, hate the idea of spending ages trying to get the avr to work dont like computer's

Quote:

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Originally Posted by adz600

Not yet all waiting on my desk, hate the idea of spending ages trying to get the avr to work dont like computer's

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make sure u r windows 7 or below it does not like the windows 8 :(

also if you are stuck get it to johnno and he will get them to me for you to program (only if you have the tool) as I have one here which does not work with soldering may work with the push on programmer ) do you have one of them ?

john

The USB wire that comes with the pololu programmer is cr@p so I'd suggest getting a better version. The one I've used is from a digital camera. I've had no issues using the programmer on windows 8 either. Just makes sure you read the pololu website on the info on the drivers etc then install avr studio 4 after

problem the cable has a larger link end so therefore does not fit into the pololu programmer??
provided cable has 6 cores the chip cable has 10

would this work
http://www.ebay.co.uk/itm/10-Pin-to-...item19e11a944e

that's not the cable that's a problem in my experience. The one that comes with the programmer is fine. Is the cable which goes between the computer and the programmer which needs replacing. I THINK its a usb to micro-usb

currently trying and filing to program, waiting forever just to download the amtel studio and the driver for the avr not installed properly, what a faf

Many thanks to Aaron and Steve for creating and sharing the code and tutorials. Thanks also to the guys who created the mods for the DX6.
I've now programmed 2 TZ85's using the Pololu AVR 1300 and everything worked as the instructions.
First time (on TZ85#1) I used the original code
Second time (on TZ85#2) the I used the DX6i code

...but something odd happened an instant after i'd programmed the second TZ85... the Pololu appeared to uninstall itself and was no longer recognised by the computer (think its died!?) anyone else had this problem with a Pololu 1300???

Tried re-installing the drivers and using on another computer etc but now the green LED only flashes a couple a times and goes out when previously it stayed solid and the other LEDs operated too.