The Fieldbus Application Layer (FAL) provides user programs with a means to access the
fieldbus communication environment. In this respect, the FAL can be viewed as a “window
between corresponding application programs.”
This standard provides common elements for basic time-critical and non-time-critical
messaging communications between application programs in an automation environment and
material specific to Type 20 fieldbus. The term “time-critical” is used to represent the
presence of a time-window, within which one or more specified actions are required to be
completed with some defined level of certainty. Failure to complete specified actions within
the time window risks failure of the applications requesting the actions, with attendant risk to
equipment, plant and possibly human life.dition 3.0 2014-08 INTERNATIONAL STANDARD NORME INTERNATIONALE colour inside Industrial communication networks – Fieldbus specifications – Part 6-20: Application layer protocol specification – Type 20 elements Réseaux de communication industriels – Spécifications des bus de terrain – Partie 6-20: Spécification du protocole de la couche application – Eléments de type 20 IEC 61158-6-20:2014-08(en-fr) THIS PUBLICATION IS COPYRIGHT PRO