block (Z.100)

Concrete graphical grammar

<block diagram> ::=
<frame symbol> contains
{ <block heading>
{ {<block text area>}* {<macro diagram>}*
{ <type in block area> }*
[<process interaction area> ]
[<block substructure area>]}set}
is associated with {<channel identifiers>}*

The <channel identifiers> identify channels connected to signal routes in the <block diagram>. Channel identifier(s) are placed outside the <frame symbol> close to the endpoint of the signal route at the <frame symbol>. If the <block diagram> does not contain a <process interaction area>, then it must contain a <block substructure area>.

<block text area> ::=
<system text area>

<process interaction area> ::=
{ <process area>
| <create line area>
| <signal route definition area>}+

<process area> ::=
<graphical process reference>
| <process diagram>
| <graphical typebased process definition>
| <existing typebased process definition>

<create line area> ::=
<create line symbol>
is connected to {<process area> <process area>}

<create line symbol> ::=

The arrowhead on the <create line symbol> indicates the <process area> of a process upon which a create action is performed. <create line symbol>s are optional, but if used then there must in the process at the originating end of the <create line symbol> be a create request for the process at the arrowhead end of the <create line symbol>. This rule applies after transformation of <option area>.

NOTE - this rule can be independently applied before or after transformation of <transition option>.

If a <block definition> or a <block type definition>, which is used in a <textual typebased block definition>, contains <signal route definition>s and <textual typebased process definition>s, then each gate of the <process type definition>s of the <textual typebased process definition>s must be connected to a signal route.

The same rule applies for <process definition>s and <process type definition>s containing <signal route definition>s and <textual typebased service definition>s.


A block definition is a container for one or more process definitions of a system and/or a block substructure.

A block provides a static communication interface by which its processes can communicate with other processes. In addition it provides the scope for process definitions.

To interpret a block is to create the initial process instances in the block.