The header file <ina90.h> defines a number of intrinsic functions of general use for the AVR processor. This file is written to be compatible, and in some cases an enhancement of, the corresponding file in version 2 of IAR's Embedded Workbench for AVR (EWA90) product.

Status register manipulation
_CLI Disable interrupts.
_SEI Enable interrupts.
Miscellaneous functions
_BREAK Insert a BREAK instruction into code
_NOP Insert a NOP instruction into code
_OPC Insert an instruction into code
_SLEEP Insert a SLEEP instruction into code
_WDR Insert a WDR instruction into code