Imagecraft c compiler and development environment for the atmel avr

ICCV8 for AVR – C Compiler for Atmel AVR#pragma interrupt_handler timer0_handler: iv_TIMER0_OVF#pragma interrupt_handler eep_handler: iv_EE_READY#pragma interrupt_handler adc_handler: iv_ADCSince interrupt vector number names are defined in the header file, they can easily bechanged for another target AVR by including another header file. New targets mustmeet hardware requirements, of course. For names supported by a distinct header,see the avr_c_lst and mega_c_lst files in the ICCV8 for AVR include directory.Assembly Interrupt HandlersYou may write interrupt handlers in assembly. However, if you call C functions inside yourassembly handler, the assembly routine must save and restore the volatile registers (seeAssembly Interface and Calling Conventions), since the C functions do not (unless theyare declared as interrupt handlers, but then they should not be called directly).If you use assembly interrupt handlers, you must define the vectors yourself. Use theabs attribute to declare an absolute area (see Assembler Directives) and use the.org statement to assign the rjmp or jmp instruction at the right location. Note thatthe .org statement uses byte address.; for all but the ATMega devices.area vector(abs) ; interrupt vectors.org 0x6rjmp _timer; for the ATMega devices.area vector(abs) ; interrupt vectors.org 0xCjmp _timerAsm header files aioXXXX.s support macros for symbolic interrupt vector definition.Syntax:set_vector_ with as in AVR data sheets and equal to theuser's asm ISR. Examples:set_vector_TIMER0_OVF t0_asm_handlerset_vector_ADCadc_asm_handlerset_vector_UART0_DRE u0dre_asm_handlerDepending on target macro expansion may result in different code. For namessupported by distinct headers, see the avr_asm_lst and mega_asm_lst files in theICCAVR include directory.134