Re: [avr-chat] How can I individualise specific CPUs?

[Graham Davies]

> On Fri, Sep 18, 2009 at 2:36 PM, Juergen Harms wrote:
> > Atmel evidently expects that either the bootloader is used
> > more or less exclusively, or the programming mechanism
> > - but not the kind of combination I had considered.

Then, on Friday, September 18, 2009 to 6:00 PM, Peter LaDow wrote:
> I guess I didn't really understand your requirement.  But the above
> seems to be a bit inaccurate.  <snip>

What Juergen means, I think, is that when you change the application program 
in a device, you either have a bootloader or you use a hardware programming 
mechanism such as ISP, JTAG or (heaven forbid) High-Voltage.  With a 
bootloader, you have a lot of freedom about what gets erased and what gets 
preserved, but with a hardware programming mechanism you generally start 
with a chip erase which wipes the entire Flash.  What Juergen wanted, if 
I've been following correctly, is for a hardware re-program to leave the 
contents of the boot loader section alone so that he could squirrel away his 
"individualizations" there.

Graham.