C & Assembly

Okay... here's something that seems to work. Simply put this code into a .S file and add it to your project.

         AREA |.text|, CODE, READONLY
         ARM
PIOA_SODR EQU 0xFFFFF430 ; set output data register
PIOA_CODR EQU 0xFFFFF434 ; clr output data register
IOPIN_PA8 EQU 0x1<<8     ; I/O pin PA8 (1 << 8)
         ALIGN
myfunc  FUNCTION
        EXPORT  myfunc
        MOV R1,#IOPIN_PA8
        LDR R0,=PIOA_SODR
        STR R1,[R0,#0]
        LDR R0,=PIOA_CODR
        STR R1,[R0,#0]
        BX LR
        ENDFUNC
        END

Then add the below line to the C file you want to call 'myfunc' from,

extern void myfunc(void);

and then just call

myfunc();

from your C file. Works for me. Of course, there might be more to it, but this seems to have been enough for me to create a function in a RealView compatible ASM file that just toggles an I/O pin that I can then call from a C file in a RealView project. Dave :-)

Okay... here's something that seems to work. Simply put this code into a .S file and add it to your project.

         AREA |.text|, CODE, READONLY
         ARM
PIOA_SODR EQU 0xFFFFF430 ; set output data register
PIOA_CODR EQU 0xFFFFF434 ; clr output data register
IOPIN_PA8 EQU 0x1<<8     ; I/O pin PA8 (1 << 8)
         ALIGN
myfunc  FUNCTION
        EXPORT  myfunc
        MOV R1,#IOPIN_PA8
        LDR R0,=PIOA_SODR
        STR R1,[R0,#0]
        LDR R0,=PIOA_CODR
        STR R1,[R0,#0]
        BX LR
        ENDFUNC
        END

Then add the below line to the C file you want to call 'myfunc' from,

extern void myfunc(void);

and then just call

myfunc();

from your C file. Works for me. Of course, there might be more to it, but this seems to have been enough for me to create a function in a RealView compatible ASM file that just toggles an I/O pin that I can then call from a C file in a RealView project. Dave :-)