Re: [Simulavr-devel] ATmega644

[Michael Hennebry]

On Mon, 21 Feb 2011, David Madden wrote:

> On 02/21/2011 10:25 AM, Sebastian wrote:
> > are there plans to support ATmega644?
> >
> > Would that be just a matter of combining stuff from ATmega16/32 (which
> > are pin compatible) and ATmega328 (which has some (all?) new features,
> > like external interrupts, new timers, USART)?
>
> It looks like there's support for several chips in atmega668base, with 
> individual chips choosing whatever peripherals are appropriate.  That looks 
> like a good place to start.

IIRC someone else did the heavy lifting to make an atmega168 and
I edited it to provide a base for the sequence atmega48/88/168/328.
They are alike except primarily for the sizes
of the memories and the vector tables.
They share a datasheet.
The 48 and 88 are small enough that they don't need
and don't have RJMP and RCALL instructions.
This is recorded in a bool member called flagJMPInstructions.
I think that it is used to ensure the correct size of ISR vectors,
but I'm not sure.

I had tried to make a 168 from a 128.
One of the many difficlties I found was that the timers weren't much alike.
As mentioned, someone else did the heavy lifting.

--
Michael   address@hidden
"Pessimist: The glass is half empty.
Optimist:   The glass is half full.
Engineer:   The glass is twice as big as it needs to be."