System status word, System status word -2 – Rockwell Automation 1747-BSN Backup Scanner Module User Manual

Page 98

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Publication 1747-UM010B-EN-P - September 2003

6-2 Module Control and Status Word

System Status Word

The System Status Word (SSW) presents a synthesis of the backup
system status. The primary objective of this word is to provide a fast
way to see if the system is working well. The status words described
in the following sections provide additional details about the
1747-BSN module and system. The SSW status bits have the following
meaning:

HSSL High-Speed Serial Link status: This bit is set when the
HSSL is faulted or when it has communication errors in one or
more 1747-BSN module in the backup system. The normal state
of this bit is OFF.

LSL Local Status Link status: This bit is set when the Local
Status Link is not working well in either the local or the remote
system. If the system has only one 1747-BSN module in each
chassis, the LSL is not be used and is always reset. The normal
state of this bit is OFF.

Buffer Full: This bit is set when the secondary 1747-BSN is
receiving a second block of data. This occurs before the reading
of the first block by the secondary SLC 5/0x. The normal state of
this bit is OFF.

System Ready to Switchover: This bit is set when the backup
system is ready to switchover. It is reset when there is one or
more errors occurring in the backup system and the system
cannot switchover. The normal state of this bit is ON.

Remote I/O Link: This bit is set when one or more of the RIO
links in the system is faulted or has communication errors. The
normal state is OFF.

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

14

0

15

13 12 11 10 9

8

7

6

5

4

3

2

1

0

HSSL

LSL

Buffer Full

System Ready to Switch Over

Remote I/O Communication

Processor Fault

Primary System

Secondary System

Number of 1747-BSN
Modules

Reserved

Reserved

Reserved

Switchover Diagnostic

SSW M1:s.3400

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