Architecture Level Safety Analyses for Safety-Critical Systems

Box 2

Composite error behaviour.

system implementation

Complete.PBA_speed_control_ab

subcomponents

speed_sensor  : device sensor.speed;

throttle  : device actuator.speed;

interface_unit  : device interface.pilot;

speed_control  : process control_ex.speed;

display_unit_inter  : device display_unit;

RT_2GHz  : processor Real_Time.two_GHz;

Standard_Marine_Bus  : bus Marine.Standard;

Stand_Memory  : memory RAM.Standard;

annex EMV2

use types  ErrorModelLibrary;

use behavior  ErrorModelLibrary::Simple;

composite error behavior

states

[throttle.Failed  and

display_unit_inter.Failed]-> Failed;

[display_unit_inter.Failed]-> Operational;

end composite;