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Re: maintainer update: add support for more AVR microcontrollers


As Eric Christopher wrote:

> >>-  {"atmega164", AVR_ISA_M323,     bfd_mach_avr5},
> >>+  {"atmega164p",AVR_ISA_M323,     bfd_mach_avr5},
> >
> >>-  {"atmega324", AVR_ISA_M323,     bfd_mach_avr5},
> >>+  {"atmega324p",AVR_ISA_M323,     bfd_mach_avr5},
> >
> >I'm not an AVR user, but from a user's perspective, this is an
> >interface change and should be documented.

> Agreed, I think that unless there's a reason you should keep both.

There is a reason: the ATmega164 and ATmega324 never really existed in
silicon, and Atmel literally renamed these devices before releasing
the first silicon for them.  Things are different for the ATmega644
which does exist in its original form, so there we do have both
devices now (and of course, we kept the old one).

Yes, this is really weird, I know.  They originally announced
ATmega164/324/644 to be one family, but funnily enough, the 164 and
324 had a wider feature set than the 644.  ATmega644 engineering
samples became available, but nothing except the datasheet for the
smaller siblings (not even their device XML files which they are using
for their own simulator).

Now that they started their `picopower' program (which is indicated by
the `P' suffix), they renamed the ATmega164/324 to 164P/324P (with
their originally intented feature set), and complemented that one by
an ATmega644P which has the same feature set as its smaller siblings,
so there are now 644 and 644P with different feature sets. :-(  I'm
all but happy about that change (as it is the first time where a
suffix letter really makes a difference for the device), but for
whatever reason, that's their marketing decision.

Likewise for the ATmega165/169 where both, the old and the 165P/169P
versions do exist.  They have the same feature set but some register
naming has been changed, so we also have both devices in the list now.

Documentation for the entire toolchain is mainly maintained as part of
the avr-libc project:

http://www.nongnu.org/avr-libc/user-manual/index.html

Once a new library release is done that supports these new devices
(most likely today or tomorrow), you'll be able to see their names in
that list.

-- 
cheers, J"org               .-.-.   --... ...--   -.. .  DL8DTL

http://www.sax.de/~joerg/                        NIC: JW11-RIPE
Never trust an operating system you don't have sources for. ;-)

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