SECTION 5 - DATA COMMUNICATIONS PROTOCOL
OPTIONAL MESSAGES
The < optional > messages returned by the Model 16 are shown below. Any
algorithm for an Entry Device should be written to recognize the structure
of the Paging Terminal responses and the key control characters in each,
but should ignore content of the < optional > messages (except to display
them to the operator). These messages are not standardized and are subject
to change.
Acknowl-
< optional >
edgement
Comments
<ACK>
* acknowledged *
Correct Logon Sequence OR Data
Block accepted by Paging
Terminal
<NAK>
ft retransmit *
Logon unrecognized, requested
again OR received <checksum>
and calculated checksum over
received data block do not
agree, data block requested
again.
<RS>
* Number Out of Range *
The number inside the < paging
field > is larger than any
User in the Database.
* User Invalidated ft
User Invalidated.
ft No Format ft
The В digit of the Full
Capcode < paging field >
references a non-existent
Paging Format type.
* Batches are Full *
A Batch was not available for
the page just received (a
retry in a few seconds will
probably result in success).
ft Transmission Error ft
This is the third time that
the last data block has been
received, each time with an
error. Go on to the next
transaction.
ft User Requires Message ft
Any page to this User requires
an accompanying message and
none was received.
<E0T>
ft bye ft
Paging Terminal has
disconnected.
Each < optional > is followed by <LF> <CR>.
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