I'm using AT91EB40A evaluation board and GCC. Everything works just fine until I use .rodata -section in my program. If I use rodata the program is compiled, but it doesn't work as it should. I would be very happy if somebody could tell me what I'm doing wrong.
---Source code I'm using looks like this---:
/* GPIO set and reset registers */ #define PIO_SODR 0xffff0030 #define PIO_CODR 0xffff0034
/* Bits to be set/reset on the GPIO port in order to toggle the LED */ #define RED_LED 1
As an aside: these macros are somewhat more obfuscated than necessary. This definition
#define REGW_ARRAY(addr) (* (volatile unsigned int *) (addr))
can be used in the more obvious fashion
REGW_ARRAY(addr) = value;
The gain is that you can use the same macro to read the register, too:
value = REGW_ARRAY(addr);
You can even achieve a macro that works like an actual array, i.e. with syntax REGW_ARRAY[addr].
Thanks about that tip, code looks now much nicer.
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