Property Management System - Communication Interface | Message Descriptions |
Release for
Maintenance
NEAX Operations
During Loss of
Communication
Recovery from Loss of Communication
Either system may request a temporary release of the data link for maintenance purposes by transmitting a Data Link Release Request message to the other system. The receiving system will perform any necessary processing and return the Data Link Release Confirmation message as soon as possible.
During the NEAX maintenance, the PMS may continue to send Nop Test messages, provided that EIA pin 6 (Data Set Ready) from the NEAX is in the “on” condition. The NEAX will turn on the EIA pin 6 “on” and respond to Nop Test messages when maintenance is completed.
While the data link is release on request of the PMS, the NEAX will continue to attempt to read Nop Test messages from the PMS. The PMS may set EIA pin 20 (Data Terminal Ready) to the “off” condition to indicate that reading should not be attempted.
When EIA pin 20 is in the “on” state and a Nop Test message is received from the PMS, the NEAX will assume that PMS maintenance has ended and that communication can be resumed.
The NEAX will continue to support the basic telecommunications functions if the data link or PMS become unavailable. Upon detection of a data link failure, the NEAX will automatically switch to the “Link Failed Mode” to perform the following tasks:
•Enable Check In and Check Out on the Attendant Console and Front Desk Terminal.
•Continue support of Message Waiting and/or Controlled Restriction if both features are active in the NEAX.
In the event of a PMS failure, it is assumed that Check In and Check Out must be done manually and entered into the PMS system at a later time. The PMS should not resume transmission of the Nop Test message and attempt to reestablish communication until the database has been brought up to date. This prevents the transmission of incorrect data prematurely through the database recovery procedure.
In cases where the PMS has remained operational during a data link failure, the PMS will continue to attempt sending Nop Test messages. A Nop Test Answer message (either Normal or Recover) from the NEAX will indicate that communication has been reestablished.
A Nop Test Normal Answer message indicates that the NEAX has had no status change during the data link failure period and has automatically switched back to the normal operating mode of an active data link.
A Nop Test Recover Answer message indicates that the NEAX has failed and that status memory has been initialized for each room with the following:
•Room Status is Occupied (Checked In),
•Controlled Restriction Level is set to the preassigned restriction,
•Message Waiting Lamps are off,
•Wake Up times are cleared.
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