User's Manual

545C Operations Manual

02/10/2012 Prerelease DCN 00001789-A

Defines the maximum length of a message. As characters are received

they are filled into a buffer and when the maximum size is reached a

new message is transmitted. The longest message that can be used by

the MCC-545C is 3,500 characters.

DIRECT, p, ETE, ON

Defines the “reliable” type of message delivery. The source unit will

retain each transmitted message and periodically retry them until the

destination unit receives them and sends an end-to-end-

acknowledgement for each message. It is possible for messages to be

delivered out of sequence when a retry has occurred causing duplicate

messages. These duplicate messages will be filtered out.

DIRECT, p, ETE, OFF

Disables the “reliable” type of message delivery. The source unit will

not retain each transmitted message for retries. Each message will be

deleted as soon as transmitted. It will be the responsibility of any

receiving equipment to manage the message reliability. If any message

gets lost in the RF network, then all characters in that message will be

lost.

5.5.4 Defining Data Relays

The ambient noise conditions at a remote station site may sometimes be

excessive and a poor communication path to the Master Station will result

particularly if the remote station is operating in a meteor burst mode. To

overcome this problem, another MCC-545C may be placed in a nearby quiet

location and used as relay station between the MCC-545C at the noisy site

and its master station. When used as a relay, the MCC-545C will

concentrate the data reports it receives from one or more neighboring

remote sites and forwards the data to the Master Station.

When used in the relay mode, the MCC-545C must be defined as a Master

Station. The relay will then receive MCC-550C sensor data GROUP reports

(see MCC-550C Operations Manual), repackage them and forward them to

the Master Station. A relay can handle a total of sixteen GROUP reports.

These reports can be in any combination; i.e., four groups from each of

four Remote units, one group from each of sixteen Remote units or any