ISSUE turnigy9x m128 freeze voltage and reboot

[alex86]

Hi everyone!!!!
I have a problem with my turnigy9x M128 processor "NO GREEN" ..
when I push the exit button repeatedly and not, not always, i have a reboot the system or I have a freeze of the battery voltage. example. the voltage is 9.7 volts happens that suddenly drops to 8,6volt without the possibility of correct it from the menu and the only solution is to restart the radio.
What can you think? I done also this mod: "9x upgrade to ATmega128A3-AU + Reboot With Horiz Trims" and indeed from right trim i haven't more the reboot problem; sometimes also appears in the upper right an exclamation mark.

ABBC3_SPOILER_SHOW

thanks to all in advance and sorry for my bad English!

ps. the buttons are original i didn't made mod on buttons

radio: turnigy 9x v2
firmware: openxt 2.1.9
processor: m128

[jhsa]

I had similar problem with one of my m128 radios that is used together with a 9xtreme board.
My fix was to remove the capacitors on all the digital pins.
You can try to remove the capacitor that is on the processor pin that connects to the exit key. I can't tell you at the moment which capacitor because it is very late here and my PC is already off. But will do in the morning if someone else didn't do it already.

You might make it happen by also press the directional keys very fast.

João

[alex86]

I made a video
https://youtu.be/CMWb4v_lWos
However, the issue is the exit botton only... i tried with others botton but the problem there isn't...
Then, Also it happens to random That the battery voltage jumps alone from 9.9 to 8.6 volt without reboot .. but does not do it always
Thanks you so much!!!!!!!!

[jhsa]

Here, try this (See Picture), and see if the problem is gone.. I bet it will be..

João

[alex86]

I do not know how to thank you!!!!!! Issue solved!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Thanks you so much you are a great!, now i have to leave the tx power on to monitor the tension down alone... and to understand if it downs normally or it has a jump tension...
I tried to push the exit and all normal!!!! I haven't reboot and jump down tension when i push exit botton!!!!
I hope that it is useful to others!!!!

[bob195558]

You may want to look at this also: (viewtopic.php?f=95&t=3594&p=99447&hilit ... oot#p99447).
Glad your problem is fixed.

Bob B.

[jhsa]

Not so fast if that happened with the EXIT key, it could very well happen with any other key or digital input. I would at least remove the caps from the other keys (Menu, left, right, down, up) as well. On my board I removed all the digital pins's caps. These are the processor pins that handle the radio's switches, as well as the trims.. Please see attached picture.

João

[alex86]

I tried and tried a lot of times with other keys (left, right, up and down, menu trim right, left horizontal and vertical) .. no nothing happens ... the problem was only on the exit button

[alex86]

i done also this mod: "9x upgrade to ATmega128A3-AU + Reboot With Horiz Trims"

[jhsa]

You may want to look at this also: (viewtopic.php?f=95&t=3594&p=99447&hilit ... oot#p99447).
Glad your problem is fixed.

Bob B.

Bob, if someone is going to replace the chip on the stock 9x board, then better replace it with an ATmega2561.
Why? Same flash memory and eeprom size as the m1218, but double the RAM. Also, I haven't read about any problems with these chips. I have one of those in my er9x radio, and I have lots of extra goodies installed in this radio, as you can imagine
Extra switches and push buttons, voice, rotary encoder, telemetry, etc.. Ahh, hall sensors replacing the gimbals's pots.. Never had a problem with reboots, hiccups, or something similar.. It runs really smoothly..
I keep trying to upgrade this radio with an Ar9x board, but at the end I always think that would be such a shame, as the radio works really well, and i can still test er9x with it of course

João

[jhsa]

I tried and tried a lot of times with other keys (left, right, up and down, menu trim right, left horizontal and vertical) .. no nothing happens ... the problem was only on the exit button

You decide what to do of course If it happens again you know where the problem is.. Let's hope it doesn't happen in flight

João

[alex86]

but why happen this? design flaw?

[MikeB]

Poor design really. With the original '64 chip there have been almost no problems, but when the '128 is used more transmitters show this problem.
The EXIT button is the only button you should need during flight.

Mike.

[jhsa]

The EXIT button is the only button you should need during flight.

Mike.

Yes, but all the radio's switches are connected to digital pins, right?? And those are certainly used during flight
Is there any reason we should think that one digital pin could have the problem, but not the others ??

João

[alex86]

However... i want to report a bug on the opentx 2.1.9 in the channel setup if select the trim there is the issue crazy the selector.. it does also in the simulator

[jhsa]

For reporting firmware bugs it is better to open another thread in the right place..

João

[alex86]

but without capacitors it is safe?... I'm sorry but I'm ignorant on the subject! The capacitor is an electrical component that stores electrical charges, and returns them when needed, right? now i removed the capacitor what happens it? what is been the issue?
that is a issue absolutely to hardware or also software? I'm sorry again maybe about my stupids question!

[MikeB]

I'm not sure whether they are present to provide "debounce" on the switches or if they are for RF suppression.
They are connected directly across the switch contacts. They are charged up through the internal pull up resistors in the processor, but are discharged directly through the switch contacts when you press the buttons, causing a high current spike for a short time. This current spike can cause a high voltgae spike that then produces the reboot/freeze you observe.
The capacitors work fine if the switches have some resistance (e.g. 1K).
The firmware includes code to debounce the buttons so there is no issue with that, and the same code will filter any RF noise.

Mike.

[jhsa]

In other words, they are not needed..

Mike, with all those high current spikes, is it possible that the processor might be slowly getting damaged over time?
I mean, mine never rebooted or had strange behavior before I upgraded the radio with the 9XT board..

João