On May 29, 2015, at 10:57 PM, Peter Feerick <
peter....@gmail.com> wrote:
> I've been out of touch with Optiboot for a while, so have forgotten where it was at... what version comes with the Arduino IDE / is pre-installed on Arduino Unos generally, and is the best way to find out if it's worth updating
Arduinos are shipping with version 4.4, and the current version is 6.2 or so.
MOST of the changes have involved adding new chips (and additional options for them), improving the ease with which one can build custom versions, adjusting for new compiler versions, writing documentation, and stuff like that. Things that don’t affect the typical Uno user at all.
But you can now say
make atmega1280 LED=J0 UART=3 BAUD_RATE=1000000
Which is pretty cool. (not particularly elegant behind the scenes, but that’s not the point.)
Probably the best summary is the “Edit History” comment section in optiboot.c
https://github.com/Optiboot/optiboot/blob/master/optiboot/bootloaders/optiboot/optiboot.c#L153
For official/current arduino boards, the most important changes are probably:
1) passes Reset cause to application in R2 (mostly)
2) No longer overwrites flash if you try to write EEPROM.
(so, the big Makefile restructuring was responsible for going to v5.x, and the changes for EEPROM for bumping to 6.x (1280 and 1284 actually support writing EEPROM now.))
If there were a lot of important changes, I’d be trying harder to get them pulled into the arduino branch.
BillW