IAR Interrupt Functions in Assembly Language

In IAR, the interrupt function can be defined as:

NAME TIM0_OVF
#define TIM0_OVF_vect 0x0A
extern timer_0_ovf_handler
COMMON INTVEC(1) ; Code in interrupt vector segment
ORG TIM0_OVF_vect ; Place code at interrupt vector
        rjmp timer_0_ovf_handler ; Jump to assembler interrupt function
ENDMOD

NAME TC
PUBLIC    timer_0_ovf_handler
RSEG      CODE

timer_0_ovf_handler:
       ;interrupt function content			
       reti	
END

Note: The address after ORG should be the absolute byte address of the interrupt vector. In this example, the word address of TIM0_OVF in the ATtiny104 data sheet is 0x005, so the byte address is 0x005*2 =0x0A.