Start Events

Start Events indicate where a process starts.

When adding a Start Event to your diagram, make sure that:

• It doesn’t have any incoming Sequence Flows.

• It has at least one outgoing Sequence Flow.

• It doesn’t have any outgoing Message Flows.

Start Events appear as circles with a thin edge. The marker changes according to the type of Start Event.

Start Event

A Start Event indicates the start of a process.

Message Start Event

A Message Start Event triggers the start of a process when a message arrives from a participant.

Message Start Event attributes

Fill in this field in the Attributes tab:

• Message Reference

  The ID of the Message that is sent or received by the Task.

  Click to view the list of message IDs and select an ID.

Define this attribute in the Output tab of the Attributes panel:

• Output

  The Data Output sent by the element.

  • To add a Data Output, click Add.

  • To remove a Data Output, select the Data Output from the list then click Remove.

  • To complete or edit a Data Output, select the Data Output from the list and fill in these fields:

    Attribute	Description
    Name	The name of the Data Output.
    Description	A description of the Data Output.
    Item Definition	The data type of the Data Output.

If you haven’t already defined the Message Definition at a global process level, you can define it in the Message tab:

• Message

  The message that’s sent or received by a participant at the start, end or during or a process.

  • To add a message, click Add.

  • To remove a message, select the message from the list then click Remove.

  • To complete or edit a message, select the message from the list and fill in these fields:

    Field	Description
    Name	The name of the message.
    Description	A description of the message.
    Item Definition	The data type of the message.

Timer Start Event

A Timer Start Event enables you to control the start of a process using a time condition. Use it to start a process at a specific date and time or at recurring intervals.

Timer Start Event attributes

Define this attribute in the Timer tab of the Attributes panel:

• Timer Event Definition

  Define the timer conditions for timer events.

  Refer to the ISO 8601 standard for date, time and duration format.

  To set the Timer Type:

  • Click and select the timer type:

    Type	Description
    None	No timer type specified.
    Recurring date	Repeated on a specific day and time in a cycle — for example, “every Monday at 9am”.
    Fixed date	A specific date and time — for example, “31 December 2021”.
    After duration	The time from the moment the process reaches the event to the moment the trigger is fired — for example, “5 minutes”.

Signal Start Event

A Signal Start Event triggers the start of another process when a Signal has been broadcast by another process.

Signal Start Event attributes

Fill in this field in the Attributes tab:

• Signal Reference

  The ID of the Signal that’s broadcast.

  Click to select a Signal ID.

Define this attribute in the Output tab of the Attributes panel:

• Output

  The Data Output sent by the element.

  • To add a Data Output, click Add.

  • To remove a Data Output, select the Data Output from the list then click Remove.

  • To complete or edit a Data Output, select the Data Output from the list and fill in these fields:

    Attribute	Description
    Name	The name of the Data Output.
    Description	A description of the Data Output.
    Item Definition	The data type of the Data Output.

If you haven’t already defined the Signal Definition at a global process level, you can define it in the Signal tab:

• Signal

  • To add a Signal, click Add.

  • To remove a Signal, select the Signal from the list then click Remove.

  • To complete or edit a Signal, select the Signal from the list and fill in these fields:

    Attribute	Description
    Name	The name of the Signal.
    Description	A description of the Signal.
    Item Definition	The data type of the Signal.