jumping to bootloader

Forum 2005-2010 (read only) Software Development
1

I'm trying to reboot an Arduino mini from within the running program. I found this on the web:

sei();
MCUCR |= _BV(IVSEL);
asm volatile ("\tjmp 0x1C00\n");

But it doesn't work reliably. Sometimes it reboots and I can download a new program, or watch the program restart, and sometimes it goes into the weeds and the bootloader never responds to downloading, and the existing program never starts up even when I don't attempt to download anything.

I need this functionality because the mini is going to be built into a small container that for practical and aesthetic reasons I won't have access to the reset switch. I will have serial communications, however. Any advice?

2

On the Mini, the bootloader starts at 0x3800 since there are 16 KB of Flash. (The 0x1C00 looks like it's for the ATmega8, which has 8 KB.)

3

Ha, no wonder it was unpredictable. It was jumping into my code and if I was LUCKY it would crash and reset. I knew this. Thanks, sometimes it just takes a second pair of eyes.