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Starting VTAM communication

The STart command establishes VTAM communication with a remote CAS that is newly defined, quiesced, or has been previously halted.


The STart command has no effect on the local CAS nor on any CAS that has an active communication link ( VTAM Act field is Yes).

After you enter the STart command, results are as follows:

  • The following message is displayed:

    BBMYAD10I START command accepted; CAS communications will start on next cycle

  • The VTAM communication link between the local CAS and a remote CAS becomes active.

  • The VTAM Act field of the CASACT view changes from No to Yes.


The STart command operates on a timer cycle. When you issue the STart command the request might take as much as 10 minutes to complete. This delay is designed to limit CPU overhead.

The following forms of the STart command are available:

  • Primary command

    The primary command is entered on the COMMAND line as follows:

    ST system

    where system is the name of a remote CAS listed in the System field.

  • Line command

    The ST line command is entered in the line command field ( CMD) at the left of the CASACT view. VTAM communication is started for the remote CAS where the command is entered.

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