NEC NDA-30115-001 Manuel D’Utilisation

NDA-30115   Revision 1.0

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Chapter 2

Architecture

The PMS communicates with the NEAX over one or more serial cables. A 
maximum of three lines can be provided as data links between the NEAX and the 
PMS.

The three lines are designated as Line 1, Line 2 and Line 3. Line 1 is used for 
Hotel Processing messages; Line 2 and Line 3 are used for Interactive 
messages.

Hotel Processing messages, such as Check In, Check Out and Message 
Waiting Lamp control, have less severe real-time requirements than 
interactive messages. Line 1 is only utilized for these messages and they will 
never be sent over Line 2 or Line 3.

Interactive messages are the Direct Data Entry messages and Maid Status 
Answerback messages. These messages require real-time interaction 
between the PMS and the NEAX and can therefore be isolated from the 
Hotel Processing messages. If Line 2 is installed, these messages will be 
transmitted over that line. If Line 2 and Line 3 are installed, these messages 
will load share over both lines. If only Line 1 is installed, these messages 
will be transmitted over Line 1.

The use of Line 1 is mandatory. If only Line 1 is installed, all messages are 
transmitted over it. Also, if Model 60 is being used, only Line 1 is necessary, 
as all of the Interactive messages are exclusive to Model 90.

It is very rare for Line 2 or Line 3 to be required. They are only needed if the 
traffic between the PMS and the NEAX is to be exceptionally heavy. And 
even the heavy traffic should only require Line 2.

The PMS may communicate with the NEAX through either an 
asynchronous transmission protocol or a bisynchronous transmission (BSC) 
protocol.