Nortel DMS-10 Series Installation, Operation And Maintenance Manual page 438

5-8 Section 060-INDP-510 System Operation Guide
File Transfer
During a polling session, the HOC interprets which files are to be polled and
request a file transfer. During a transfer of files, the BMC determines the file
requested by the HOC. The CPU directs that the file move from disk to the
SCSI Interface PCA, and then to RAM. The CPU directs the file to the 56K
Interface PCA for file transfer.
Once a file is successfully transferred, the BMC sets the File Sent flag (mark
file as secondary). If a bad transmission or missing data is sensed,
retransmissions of specific blocks can be requested by the HOC. The HOC
can request up to thirty retransmissions (one request; 29 retries) before
disconnecting. After polling, the HOC may ask for another file, request a
system report, or abort the session.
The modems communicate over the link until the BMC has transmitted all of
the required data. During polling, a low level dialogue takes place, which
verifies that blocks of data are being transmitted and received properly.
File Management
At the completion of sending all data requested, the HOC disconnects the
link.
Maintenance Communication
Two RS-232C communication links on the Quad SIO PCA are reserved for
communication links between the BMC and a customer-supplied terminal for
maintenance communication. The first link provides local maintenance
terminal access. The second link provides maintenance access via SDI port
(DMS-10 only). There is a third link on the Quad SIO PCA that is used for
program download by Nortel. Like the modem links, the printer
communication path connects the printer to the Power and Alarm
Communications PCA before reaching the Quad SIO PCA. This link
provides the Human-Machine Interface for the BMC. The type of
information passed over this link includes commands, messages, and alarm
information.
The information on the RS-232 link is routed from the Power and Alarm
Communication PCA to the Quad SIO PCA in the active processor.
Commands received over this link are treated as interrupts by the BMC CPU.
The active processor interprets the command and acts on it. During normal
operation, log and error messages are generated by the BMC. These
messages are output through the Quad SIO PCA to the maintenance terminal.
297-6201-502 Standard 01.02 September 2000
Note: During polling, the only activities that are indicated on the
terminal are when the session was established and when the session was
disconnected.