Author Topic: TinyESC- Possibly Blown?  (Read 2967 times)

roybrox

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TinyESC- Possibly Blown?
« on: January 28, 2015, 05:48:01 pm »
Hi All,

I've got a pair of TinyESCs enclosed in a pretty tight metal cylinder right up next to a pair of SilverSparks, 1 ESC per motor. I was just putting this whole thing back together when I noticed than one of the ESCs, even though it would flash with power it would not 'recieve' a signal from the receiver (R415x) and continue to blink slowly red in 'Standby' mode. I isolated the signal pin and it looks like it's connected and there's no breaks in it. Also, the BEC works just fine and it can give power to the radio. No amount of goading will get it to send signal to the motor (or even look like it's receiving). I also tried re-calibrating, but it doesn't seem like that did anything.

It looks like there's a small brown spot over Pin 7 on the H-bridge, but that could just be discoloration/wear and tear. Is there a chance that my battery shorted through the TinyESC and killed it? Has anyone had this problem before seen these symptoms before? I know there was a brief frame-grounding issue with my bot, but I was pretty sure I grabbed all the loose ends before trying to put it together this time with this new ESC.
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zacodonnell

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Re: TinyESC- Possibly Blown?
« Reply #1 on: January 28, 2015, 09:09:33 pm »
If the ESC is showing no signal by blinking the LED then the processor is probably ok (since it is executing the "slow blink" code) and the part of the controller responsible for driving the motor isn't being told to do so so it may be fine too.

Do you have other things (like the other tinyESC) plugged into the RX so you're sure that it is linked to your radio, powered up, and pushing signals through the pins? If so, try swapping the plug positions between the working part and the non-working part in case it is the port on the rx.

Also, you probably already checked but is it possible you flipped the plug around on the RX?  I did this when troubleshooting the other day and it totally messed up my decision tree :)

-Zac

roybrox

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Re: TinyESC- Possibly Blown?
« Reply #2 on: January 28, 2015, 10:16:44 pm »
I've got a second TinyESC plugged in that works and connects just fine, hitting all the limits where it should. I've played musical positions with all of the connector positions and all of the positions seem to work fine; I've even isolated the signal wire on the faulty TinyESC and plugged just it into the RX while using the other ESC as a BEC and still gotten nothing.

The R415X uses some really annoying micro JST connectors that can't be flipped around; that and a faulty wiring job on my part were the first things I checked.
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MikeNCR

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Re: TinyESC- Possibly Blown?
« Reply #3 on: January 28, 2015, 10:41:07 pm »
One odd thing it could be is there may be a break in the signal wire somewhere that's hidden by the insulation. If there's an area that looks damaged that could be the problem. Easiest way to check is to shave a bit of insulation off the signal wire near the esc and use a multimeter to see if there's an open circuit between the plug and esc. (make sure to tape over the shaved off area once you're done)

roybrox

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Re: TinyESC- Possibly Blown?
« Reply #4 on: January 29, 2015, 12:35:31 am »
I also checked that: I went straight from the terminal where the wire's soldered to the pin on the connector, checks out just fine.
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zacodonnell

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Re: TinyESC- Possibly Blown?
« Reply #5 on: January 29, 2015, 12:55:27 pm »
The only other thing I can think is a broken trace on the board between the solder joint and the controller chip. Sounds like you were pretty thorough...

-Zac

FingerTech

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Re: TinyESC- Possibly Blown?
« Reply #6 on: January 30, 2015, 02:07:59 pm »
It is possible to blow input pins on microcontrollers (usually by shorting a power supply to the pin) and still have them run code fine.

Any chance that might have happened?
Kurtis Wanner
FingerTech Robotics

roybrox

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Re: TinyESC- Possibly Blown?
« Reply #7 on: January 31, 2015, 11:20:15 pm »
That's what I've been suspecting; I briefly had a shorting problem with my battery and frame (which is dangerously close to my motor leads), but I got that tidied up. I'm gonna go ahead and order a few more TinyESCs to fix that up and to have around just in case.

Would the microcontroller itself be damaged, or only the connection? I can attempt a re-flow if you think that could save it.
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FingerTech

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Re: TinyESC- Possibly Blown?
« Reply #8 on: February 02, 2015, 07:51:03 pm »
It would be internal in the microcontroller chip.  :(
Kurtis Wanner
FingerTech Robotics