bootloader only after reset

[Hasi123]

Have you figured out why the bootloader only works after a reset? I would expect it to run immediately after power on.

I experimented with avr_boot a while ago and only could get it to work if I put a small delay of 5ms at the beginning of the bootloader to let the SD card power up. I tried to do the same with your bootloader, but unfortunately the compiled binary is 2050 bytes (2 bytes too much 😡).

[prunkdump]

Hi !

I don't fully understand your problem. If the bootloader start at each power-on it will load the firmware from SD card each time. This is risky.

If your compiled bootloader is too big. Simplify the "FIRM.HEX" test.

if( data[0] != 'F' || data[1] != 'I' || data[2] != 'R' || data[3] != 'M' || data[8] != 'H' || data[9] != 'E' || data[10] != 'X' ) { entryFilenameFound = false; }

like this for exemple :

if( data[0] != 'F' || data[1] != 'I' || data[8] != 'H' || data[9] != 'E' || data[10] != 'X' ) { entryFilenameFound = false; }

[Hasi123]

Isn't that how the bootloader should work? I would expect it to load the firmware on each startup. You can then delete the firmware at the beginning of the main code or just leave it.