Traxxas TQ2.4 Channel 4 and 5 separating

[Banditt]

This is for those who have tried modding a newer TQ2.4 HO radio. I'm curious to see if there is a way to separate channels 4 and 5 without having to come up with custom software or some insane hack. Right now I have channel 3 on a 3 position rocker switch and it works great. However I'm limited to 4 channels the way the other 2 work. You can't just use two 2 position switches on the last points on the board. Example

switch 1 to ground + switch 2 open = channel 4 moves

switch 1 open + switch 2 to ground = channel 5 moves

switch 2 to ground moves channel 5 + then switching switch 1 to ground moves channel 5 back to original position, channel 4 never moves

switch 1 to ground moves channel 4 + then switching switch 2 to ground moves channel 4 back to original position, channel 5 never moves

Wiring the stock thumb rocker on the handle to both pads and flipping the switch results in both channels 4 and 5 moving the same dir (the dir chan 4 would move)


I'm guessing there is no way to physically separate the channels, that it must be done with a software hack. Am I correct? Yes I've used search and yes I've spent days reading all the threads on the TQ5 build. The problem is that the original poster solved the problem by creating a custom board that would give him full control over all channels. I'm not interested in doing that. I just want to separate them so I can turn lights on. Any thoughts? Thanks for any help you guys could give.

[wantAsummit]

Originally Posted by Banditt

I just want to separate them so I can turn lights on.

You should be able to run CH4 and CH5 with 2 independent 2-position switches, I think you are just about there. This would be ideal for running an LED controller.

If you were interested in combining CH4 and CH5 to act as a 3-position switch, please vote here: http://www.rccrawler.com/forum/showthread.php?t=264496

[Banditt]

Originally Posted by wantAsummit

You should be able to run CH4 and CH5 with 2 independent 2-position switches, I think you are just about there. This would be ideal for running an LED controller.

That doesn't work. If you want I can take the radio back apart and solder the two 2 position switches back in place and video it to show you what happens. I think that there is a software limitation for channel 4 and 5. If 4 is turned on 5 cannot be and vise versa. I'll vote right now.

[wantAsummit]

Originally Posted by Banditt

That doesn't work. I think that there is a software limitation for channel 4 and 5. If 4 is turned on 5 cannot be and vise versa.

I have an unmodified TQ4 Link at home that I use for my Summit. I'll take a look at it tonight and post back. I re-read your original post and now understand what the limitation is that you described. You don't have exclusive indepentant access to CH4 and CH5. I'll see if I do or not.

[Banditt]

Originally Posted by wantAsummit

I have an unmodified TQ4 Link at home that I use for my Summit. I'll take a look at it tonight and post back. I re-read your original post and now understand what the limitation is that you described. You don't have exclusive independent access to CH4 and CH5. I'll see if I do or not.

That would be awesome! I'd really like to tackle this problem and get it solved. LOL I went to sleep last night trying to think of a logical way of using switches to run the channels independently from one another. It was in my dreams! Looks like each channel depends on the other being switched off in order to function.

[wantAsummit]

Originally Posted by Banditt

Looks like each channel depends on the other being switched off in order to function.

Wow, I guess I never evaluated that section carefully enough. I knew that CH4 and CH5 each worked, but apparently never tried both at the same time. Unfortunately, my stock radio acts just like yours. This is with out a doubt a built-in firmware limitation. Sorry for the bad news, I gave up on investigating the stock functionality after the first few limitations I found. It looks like we are left with a 3-position conversion or a port expander like spoo76 suggested.

One more option for your specific case of running LEDs. If you can handle one set of LEDs coming on before the other, you may be able to use the TQ in stock form. Remember that servo reversing is available for CH4 and CH5. Position 1 would be both off, Position 2 would be CH4 on, Position 3 would be both on.

[Banditt]

Ok great now I don't feel as if I've done something wrong and have someone else to backup my claims. Next question. Do you know if it is possible to use JTAG equipment to sniff the firmware and possibly reverse engineer it? I've got the JTAG equipment and a little knowledge but I'm no expert. I wonder if anyone else has tried this?

[bjs1785]

I am having this SAME problem. I bought the tq4 only to use that 3 way switch for a winch.

It looks like I can just move the wires on the red ch 3 switch to a new 3 way switch, and channel 3 will be good to go as a 3 way? Is this correct?

Could I also just remove the wires from the CH4/ch5 3 way switch, and run the wires from ch 3 to that switch. Basically eliminating ch 4 and 5, but I dont need them.

So frustrating, I feel like traxxas is mis-advertising this 3 ways switch. Its really not a 3 way switch. Frustrating!!!

Thanks!

[Banditt]

You have PM. The stock switch is fine to use. Just swap wires and you will have channel 3 off the toggle working left-center-right. The thumb switch then makes channel 4 and 5 turn 90 degrees to the left.