Symmetricom 1000 User Manual
097-58001-02 Revision G – April 2008
TimeProvider User’s Guide
37
Chapter 1 Overview of the TimeProvider
Reference Input Signals
Subtending Mode
illustrates which input is the active system reference under several
different input conditions when the TimeProvider is in the Subtending mode.
Table 1-2. SSU-Based Reference Selection Scenarios
Sequence
QLevel on
PRS
QLevel on
INP1
QLevel on
INP2
Active Reference
Non-Revertive
1
Note:
1
Non-revertive example. Priority Levels set to: PRS = 3, INP1 = 3, and INP2 = 3
Revertive
2
2
Revertive example. Priority Levels set to: PRS = 2, INP1 = 1, and INP2 = 2
1
2
2
2
PRS
INP1
2
4
2
2
INP1
INP1
3
4
4
2
INP2
INP2
4
4
4
4
INP2
INP1
5
4
4
2
INP2
INP2
6
4
2
2
INP2
INP1
7
2
2
2
INP2
INP1
8
2
2
LOS
PRS
INP1
9
2
LOS
2
PRS
PRS
10
LOS
LOS
2
INP2
INP2
11
LOS
LOS
LOS
Holdover
Holdover
12
LOS
LOS
2
INP2
INP2
13
2
LOS
2
INP2
PRS
14
2
2
2
INP2
INP1
Table 1-3. Subtending-Based Reference Selection Scenarios
Sequence
QLevel on
INP1
QLevel on
INP2
Active Reference
Non-Revertive
1
Revertive
2
1
1
1
INP1
INP1
2
2
1
INP2
INP2
3
2
2
INP2
INP1
4
2
1
INP2
INP2
5
1
1
INP2
INP1
6
1
LOS
INP1
INP1