Re: [avr-libc-dev] [task #3693] Add new devices: mega 640-1280-1281-2560-2561

[Bertolt Mildner]

Hi Marek,

Am Tuesday, March 15, 2005 um 12:13:56 PM hast du geschreiben:

> Follow-up Comment #4, task #3693 (project avr-libc):

> According to the datasheet, all these devices (not just 256x - 640/128x too!)
> store a 3-byte PC on stack.  This means they all need GCC changes (new

Yes, the datasheet can lead to this conclusion, but it would not make
much sense.

If the IAR Tools are right then only the 256x uses 3-byte addresses on the
stack.

IMHO, the current datasheet does a very very bad job on pointing out
all the (small but mostly vital) differences between 640/128x and
256x!

Another example is in the "Instruction Set Summary". It says that CALL
takes 5 clocks, but i would be very surprised if this holds true for
640/128x (64 and 128 take 4 clocks per CALL).


Bertolt

-- 
Best regards,
 Bertolt                            mailto:address@hidden