Siemens SIMATIC TIWAY 1 - Manual (Page 128)

HOST COMMAND SET REFERENCE
UNILINK HOST ADAPTER 5–43
USER MANUAL
will be set, disabling the trigger macro. Once the action macro
has successfully completed, the trigger macro behaves as any
non-linked macro. If the trigger macro is repetitive or the freeze
option detected no change, it will be enabled. The trigger macro’s
exception flag will be set if a change occurred, but not until the
action macro completes processing.
If the action macro cannot be executed for any reason, such as the
secondary has gone offline, the macro link will be terminated.
The trigger macro will then continue to execute as a non-linked
macro.