Makerbuino SD Card Makes the Unit Reset [SOLVED]

Hey, thanks for joining the forum.

Iā€™m sorry that you couldnā€™t afford a MAKERbuino kit for yourself. You couldā€™ve reached out and I might have given you a discount :slight_smile:
Anyways, congratulations on a cool build!

This looks like your microcontroller is resetting due to power supply issues (brownout).

The power supply that youā€™re using looks like a micro USB cable which is 5V.

You need a 3.3V output, but the LM317 needs 3V of bedroom to operate properly.

That means that you either need a microcontroller with a lower dropout voltage or you need to deliver a minimum of 3.3V+3V=6.3V in order for it to work properly.

Hope this helps and good luck with your build!

Wow! I didnā€™t expect anyone to reply so soon, but from the creator himself, I am truly grateful. :grinning:

I already copied your schematics and I donā€™t want to abuse your kindness by taking you up on your offer of giving me a discount knowing that people who bought this kit paid full price or more. I just want this thing to work like it should. But thanks, anyways.:blush:

So I did what you advised, but unfortunately, it still gave me the same results. Iā€™ve read the datasheets for the lm317t, and it said that the voltage difference between input and output should be 5v. So I followed through. The outcome was no different.:expressionless:

There arenā€™t so many components available locally, so I have to settle with what I can obtain through desoldering scraps from old radios and electronics.

Perhaps the only way I can play games on this is to directly upload the code to the microcontroller. Guess Iā€™ll try that.

Thanks for replying!

Hey,

Thanks for your reply.

  1. Please measure the voltage on the microcontroller. Is it 3.3V?
  2. Is the SD card that youā€™re using >2GB and FAT16 formatted? It needs to be like that or else it wonā€™t work

Yes. Iā€™ve measured the voltages and the sd card is 2gb (FAT).

Hey,

The things that Iā€™d check if I were you:

  1. try doing it with another SD card
  2. Check if the files on the SD card are unzipped and in the root folder
  3. Check if there is LOADER.HEX on the SD card
  4. check the connections between the microcontroller and the SD card with a multimeter

Hope this helps

Also, check once again if youā€™ve burned the bootloader properly

Hi,
Iā€™ve encountered this problem before (it resets when I press c) when I built my own gamebuino (before the actual one arrived) and I discovered it was because the bootloader was not flashed.
Maybe you could check if the bootloader was flashed correctly?
I guess you havent flashed the bootloader because you do not have the ICSP headerā€¦

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@YEA, congrats on building your own MAKERbuino as well and thanks for supporting the project :slight_smile:

I agree, that might be the case here. I first though it was connected to the power supply isues, but not having a bootloader will have this effect here

Itā€™s a new microcontroller that I bought. Maybe thatā€™s all thatā€™s missing. Iā€™ll try to burn the bootloader with another arduino by following their instructions online. I highly appreciate the reponses.:blush:

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Also, MAKERbuino uses a different firmware from standard Arduino, make sure you flash the correct one!

May I ask if you can tell me what is the firmware?

http://legacy.gamebuino.com/wiki/index.php?title=Bootloader
there are instructions to flashing in the middle, but scroll down to bottom of page to download

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Hello, Albert
Can you share more information of that investigation? I am using buck-boost converter (with no filter) instead of LDO, which gives 3.3v Ā± 50mV ripple at 5kHz, and expereincing the same issue with unit rebooting. So I am wondering, what are the requirements for the voltage stability and level, in case that was the issue you discovered.
Funny thing is - arduino ide has a builtin SD example sketch, which works fine, showing SD capacity (1GB), vendor code, etc.
Buckboost IC is TPS63031, rated max 800mA.
Fusebits have BOD disabled.
Thank you.

EDIT: adding HUGE low pass filter 470uH+1500uF gave no effect. This eradicated standby ripple completely, but I was still getting -50mV drop at the moment controller initializes card.
Next thing, I swaped buck-boost IC with 1117 LDO - this gave -20mV drop at initialization, but the thing still reboots. What the hell

Hey,

Thank you for joining the forum.

ummā€¦ I am not sure which information youā€™re talking about, but Iā€™d recommend sharing a schematic and some photos of your design and maybe Iā€™ll be able to help you from there

Thank you for replying so quickly.
The info I am interested in - what was the evidence that made you conclude LM317 (LDO Budoy_ness used) was the root of the problem, and why it was incompatible in general. It is rated 1.25A, so why not?

I donā€™t have a schematic, here is my pcb. I know, it is not much of a help)

EDIT: Nailed it, it was a bootloader issue! Reflashing it did the trick.
By the way, is gamebuino_boot.hex, built 30.12.2016, the latest version? Iā€™ve got mine here

Great, Iā€™m glad youā€™ve managed to fix that.

The problem for LM317 is that it requires 3V of headroom (VI ā€“ VO) to operate in regulation. This means that if you want an output of 3V, you need an input of 6.3V and the battery used on MAKERbuino only has 3.7V of nominal voltage.

Btw nice PCB. Woah, your vias are huge, you can try making them smaller, you know :slight_smile:

Those huge vias are for buttonsā€™ leads, but leads are shortened in order to not come out this side to puncture the battery. Other vias are 0.3mm.

As for LM317 - agree, not suitable for lithium battery, but dropout voltage is not constant 3v. I would say, you could barely make it to 3.3 output on 5v input
ICFoT

Back to the bootloader. Can you please pinpoint the link to the latest version?

Iā€™have also found this bootloader, worked for me. It is 2K size, so fusebits must be set L:FF H:D8. Anyone else encountering bootloader stuck in ā€œflashing loaderā€ state - check your SD is <2G size, has no errors, formatted FAT(16) and LOADER.HEX is present on it.

Always check your fusebits and remember that arduinoā€™s stock bootloader is incompatible with gamebuino.

Here is the latest bootloader:

Thanks for the rest of the tips

Hi. Albert! i am trying to make makerbuino from opensource project. I complet almost all steps in building, but i canā€™t setup any game from sd card. Cardā€™s size is 1 gb (16kb FAT). May be it is some problems with bootloader. Can you give me permission to download a file above?
PLs write how i should download game.HEX in proper way to sd card?
Thanx a lot!)

MAKERbuino.zip (81.7 KB)

Hey, hereā€™s the file, happy making! :slight_smile: