The boot loader is a small program sitting on address $3C00 in the flash memory. If you push the boot loader button in the PC application the application software jumps to $3C00 and the boot loader starts. You can choose your new application software (.bin) and and if you click on the file, the file is written into the boot loader portion of the flash memory. Boot loading a new boot loader caused a crash in my situation and I ruined the ATMEGA32. I couldn't read/write  it anymore, like it was locked with the fusebits.

By the way I created the .bin file with  BASCAVR.exe, which is very usefull to me.

I tried to use eXtreme burner to flash both the application software and the boot loader. But that didn't work because eXtreme is erasing the chip, before burning a new file in it. And you can not put that feature of by a tick or something similar.

But BASCAVR is ok because you can put multiple files in the buffer, before burning the buffer. Clever,....!

I tested the bootload button on the application software and indeed, I could select a file, a .bin file, and load it to the Tuner ATMEGA32.

 

 

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