Atmel CAVR-4 Manual De Usuario

CAVR-4

Descriptions of intrinsic functions

Reference Guide

To use intrinsic functions in an application, include the header file 

intrinsics.h

. 

Note that the intrinsic function names start with double underscores, for example:

_ _segment_begin

The following section gives reference information about each intrinsic function.

_ _delay_cycles

_ _delay_cycles(unsigned long int);

Makes the compiler generate code that takes the given amount of cycles to perform, that 
is it inserts a time delay that lasts the specified number of cycles.

Note: The specified value must be a constant integer expression and not an expression 
that is evaluated at runtime.

 _ _disable_interrupt

void _ _disable_interrupt(void);

Disables interrupts by inserting the 

CLI

 instruction.

_ _enable_interrupt

void _ _enable_interrupt(void);

Enables interrupts by inserting the 

SEI

 instruction.

_ _extended_load_program_memory

unsigned char _ _extended_load_program_memory(unsigned char 

_ _farflash *);

Returns one byte from code memory.

Use this intrinsic function to access constant data in code memory.

_ _segment_end

Returns the end address of a segment

_ _sleep

Inserts a SLEEP instruction

_ _swap_nibbles

Swaps bit 0-3 with bit 4-7

_ _watchdog_reset

Inserts a watchdog reset instruction