Re: [Simulavr-devel] Support for atmega2560?

[ThomasK]

Hi Markus,

> My impression is, 1284p implementation works up to 64 kB, only. Running the 
> very same code compiled for ATmega644 works, when compiling and running for 
> ATmega1284P I get such warnings:
> WARNING: file rwmem.cpp: line 231: Invalid write access to IO[0x90]=0x1, 
> PC=0x3ba6
> WARNING: file rwmem.cpp: line 231: Invalid write access to IO[0x91]=0x9, 
> PC=0x3bac
> WARNING: file rwmem.cpp: line 231: Invalid write access to IO[0x71]=0x0, 
> PC=0x3bb0

Hm ... this io addresses point to some timer peripheral things. And in 
simulavr mega644 and mega1284 habe the same code (especially for io 
assignment) except sizes of RAM, Flash and EEPROM. So, for me int not 
plausible, that this should work on mega 644 and not on mega1284.

But, of course a bug in the code! In code, this addresses are not 
assigned, if you look into datasheet, there are some registers at this 
addresses for timer control.

Why you can't see problems with mega644 but see this warnings for 
mega1248 ... is unclear. Code exclusion or inclusion, if compiled for 
644/1284? (some #ifdef stuff?) Maybe a bug in register description?

If you would get a problem with code in addresses greater 64k, then I 
would assume, that you would get other messages ... invalid code and such.

cu, Thomas