Development Tools

Using saddr area (#pragma saddr)

This notifies the compiler of a variable that is to be assigned to the saddr area.

[Function]

-	Initialized variables are allocated to the .sdata section.

-	Uninitialized variables are allocated to the .sbss section.

-	Address reference always returns a near pointer.

-	External variables and static variables in a function are allocated to the saddr area when they are specified with #pragma saddr.

-	#pragma saddr handles even a variable to which the __far keyword is added as if __near was specified without a warning being output.

[Effect]

-	Instructions that access the saddr area are shorter than those accessing the normal memory area and their object code also becomes smaller, leading to improved execution speed.

[Usage]

-	Declare #pragma saddr before the first declaration of a variable.

#pragma saddr [(]variable-name[,...][)]

[Restrictions]

-	If there are multiple declarations for the same variable and #pragma saddr is written at the location where the second or subsequent declaration takes effect, correct operation is not guaranteed.

-	If another #pragma is specified, a compilation error will occur.

[Example]

#pragma saddr saddr_var

extern int saddr_var;

void func(void)

        saddr_var = 0;

[Remark]

-	Difference between the __saddr keyword and #pragma saddr

-	The __saddr keyword cannot be used together with the __near or __far keyword, and a compilation error will occur if used so.

-	#pragma saddr handles even a variable to which the __near or __far keyword is added as if __saddr was specified without a warning being output.