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Arduino sketch for burning new bootloaders
Arduino C
Latest commit d8bb852 @WestfW Update Readme



Copyright (c) 2011 by Bill Westfield ("WestfW")
Distributed under the terms of the "MIT OSSW License."

Optiloader is a sketch designed for bulk upgrading of Arduino board
bootloaders using another Arduino as a device programmer.  It stores
multiple copies of the optiboot bootloader in program flash memory.  When
run (ie by hitting reset), it probes the target device, figures out the type
of CPU (ATmega8, ATmega168, ATmega328, ATmega328P) and initiates upload of
the bootloader and appropriate fuse programming.  Since optiLoader runs
entirely with the Arduino and there is no communications with a host PC
required, this can procede very rapidly, and is not subject to interference
of (for example) avrdude with auto-reset.

The internal copies of the bootloader are prepared manually from the .hex
files compiled in the bootloader directories.  (There's an easy editor macro
process, but it is manual.)

While communication with a host PC is not required, the sketch does send
status information to the serial port at 19200bps.  Here's a sample:

OptiLoader Bootstrap programmer.
2011 by Bill Westfield (WestfW)

Target power on! ...
Starting Program Mode [OK]

Reading signature:950F
Searching for image...
  Found "optiboot_atmega328.hex" for atmega328P
  Start address at 7E00
  Total bytes read: 502

Setting fuses for programming
  Lock: 3F FFE000  Low: FF FFA000  High: DE FFA800  Ext: 5 FFA400

Programming bootloader: 512 bytes at 0x3F00
  Commit Page: 3F00:3F00
  Commit Page: 3F40:3F40
  Commit Page: 3F80:3F80
  Commit Page: 3FC0:3FC0

Restoring normal fuses
  Lock: 2F FFE000

Target power OFF!

Type 'G' or hit RESET for next chip
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