Re: [avr-gcc-list] Porting code to/from codevision

[David Kelly]

On Nov 23, 2005, at 6:15 PM, Peter Harrison wrote:

> Specifically, I have a largeish lookup table (4k) and menu data  
> (titles, function pointers etc) to deal with. I have considered  
> using a macro for the data access so that I can write
>
> value = READ_FLASH_BYTE(addr);
>
> and define the macro as null in CVAVR or as required by AVRGCC.  
> However, I am less sure about the declarations and can't get my  
> head round a suitable dodge.
>
> Just to make things more awkward, I may well want this code to  
> compile with the ARM and H8 GCC compilers. On the PC, I simply have  
> a macro that defines 'flash' as null and the code compiles just fine.
>
> Is this overdoing the portability thing?

No, thats what macros and include files are all about.

In general avr-gcc uses macros to modify data access to FLASH, and to  
modify for declaring data stays in FLASH and should not be copied to  
RAM during startup. Essentially all you have to do is create NULL  
versions for Codevision or insert whatever special things Codevision  
likes.

--
David Kelly N4HHE, address@hidden
========================================================================
Whom computers would destroy, they must first drive mad.