AVR Boot load problems

[Roxy-3D]

I think I lost the boot loader on my Rumba board. I used a USBasp and Arduino to put a boot loader back on the board. I am now once again able to upload code to the board using the normal USB cable and AVR ISP.

But... Sadly, the LCD Panel just keeps screeching the buzzer and the uploaded code doesn't seem to do anything. Are there specific boot loaders I should try? I'm open to any recommendations that anybody has!!! Can I use the USBasp to upload the Marlin firmware?

[ManuelMcLure]

You might want to look at http://forum.arduino.cc/index.php?topic=356420.0 post #5 - there appears to be some issue with the Mega2560 fuses that needs to be resolved before uploading a new bootloader will work.

[Roxy-3D]

Thank You! I did verify the Marlin firmware is running. I can do a M114 and a M119 and get expected numbers. But NOTHING else works!!!!! And the stupid LCD Panel just keeps screeching at me.

@Bob-the-Kuhn Bob... Why do the boot loaders disappear some times? And why are the fuses important when you put them back? I know the Marlin firmware is running because I can do a M114 and M119 and it talks to me.... But it is like the reset of the chip isn't working. I know you had trouble reloading a boot loader... Can you guide me through what I need to do?

@ManuelMcLure I did pull down that page and everything it referenced. But so far... I've only skimmed it. I'll need to spend an hour reading everything tomorrow. THANK YOU for the link!!!!!!

[ManuelMcLure]

That behavior seems very odd. Once the boot loader has started Marlin up its job should be done. Unless the boot loader is setting up something wrong on the chip before passing control on to Marlin, which expects a specific state...

[Roxy-3D]

I only skimmed the links contained in the first link you posted. I'll dig in deeper tomorrow. But there is some bug in the Mega-2560 with regard to fuses and being able to see the entire memory space.

If only half of Marlin is there... That would explain a lot. (I suspect this theory is way too simple and not correct. But something like this would explain what is going on.)

[igorepi]

USBASP with latest official or stock chinese firmware don't work with Atmega chips with more than 128Kb flash, i.e. Atmega2560. In order to program/verify all the Atmega2560 flash you'll need reflash USBASP with modified FW, https://github.com/PeterVH/usbasp/blob/master/bin/firmware/usbasp-v1.5.hex for example. Or you can edit official firmware yourself as in this commit: this single edit will be sufficient.

The problem is explained here.

[boelle]

@Roxy-3D should this one still be open?

[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.