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Topic: bootloader should use pullup (Read 1 time) previous topic - next topic


If there's a spare byte or two in the bootloader, future versions should be modified to turn on the ATmega's internal pullup resistor on the RX data line to prevent noise lockups on boot when there's nothing attached to the RX line.



The last time I build the bootloader I think there were two spare bytes. But that is enough. I suppose as long as someone might consider touching the bootloader, it would be nice if the programmer 'reset' command was hooked up. Then we wouldn't have to wait for the thing to time out after loading a new sketch. The IDE could just tell it to reboot after the last bit was loaded.


I'm not sure that it's worth changing the ATmega8 bootloader, since all of the new boards use the ATmega168.  They're definitely good suggestions for the ATmega168 bootloader though, and that one's not so tough to change because we're giving it 2 KB of space, so there's lot of extra room.  I'll add it to the to-do list.


While we're on the bootloader, would it be possible to decrease the timeout value, so programs boot a little faster too.

This might require a little more coordination on syncing the reset button push,  but for beginning programmers, that are making a lot of simple changes, this hang time adds up.

paul badger


Yea, the hope is also to enable automatic resetting of the boards one of these days, which would enable the whole process to be much faster.  Actually, on the 168 bootloader, the delay after uploading can be greatly reduced - the only reason it was so long on the ATmega8 bootloader was that it saved code space to use the same delay both before and after uploading.

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