GENERAL NOTES
SUMMARY OF XSF FLAGS
(Communications Operation of XSF flags is required)
XSF2 - (Detector 3) - Transfer of tram demand from PHE / Kooyong (2413).
XSF10 – Turn on P1 Wait State
GENERAL OPERATION
1.                              Tram leaving Detector 2 sets MSS1 for the duration specified in Special Purpose Timesetting No. 22.
2.                              Tram leaving Detector 4 sets MSS2 for the duration specified in Special Purpose Timesetting No. 22.
3.                              P1 Wait State Output drives an alternating Variable Message Display, which can be activated by trams travelling in either direction along Princes Highway East – the detail of this operation is described in the sections immediately below.
OPERATION FOR WestBOUND TRAMS (SPECIAL COUNTER 1)
(Refer also to P1 Wait State summary on Page 4/2)
NORMAL CONDITIONS
CALLING DETECTOR
Detector 1 when activated:
-         Increments Special Counter 1 by 1 for every tram
-         Starts Timer 1 (Special Purpose Timesetting No. 9).  While Timer 1 is timing, any subsequent activation by this detector will be ignored.
-         Starts Timer 2 (Special Purpose Timesetting No. 10).  For any subsequent activation, restart Timer 2 if it is still timing.  When Timer 2 expired, set Special Counter 1 to zero.
CANCELLING DETECTOR
Detector 2 when activated:
-         Decrements Special Counter 1 by 1 for every tram
-         Starts Timer 3 (Special Purpose Timesetting No. 9).  While Timer 3 is timing, any subsequent activation by this detector will be ignored.
FAULT CONDITIONS
CALLING DETECTOR
If Detector 1 is alarmed:
-         Set a continuous MSS3 flag.
-         Turn on P1 Wait State and reset Special Counter 1 to zero.
CANCELLING DETECTOR
If Detector 2 is alarmed:
-         Set a continuous MSS4 flag.
-         Turn on P1 Wait State and reset Special Counter 1 to zero.
OPERATION FOR EastBOUND TRAMS (special counter 2) 
(Refer also to P1 Wait State summary below)
NORMAL CONDITIONS
CALLING DETECTOR
XSF2 (Detector 3) when activated:
-         Increments Special Counter 2 by 1 for every tram
-         Starts Timer 4 (Special Purpose Timesetting No. 9).  While Timer 4 is timing, any subsequent activation by this detector will be ignored.
-         Starts Timer 5 (Special Purpose Timesetting No. 10).  For any subsequent activation, restart Timer 5 if it is still timing.  When Timer 5 expired, set Special Counter 2 to zero.
CANCELLING DETECTOR
Detector 4 when activated:
-         Decrements Special Counter 2 by 1 for every tram
-         Starts Timer 6 (Special Purpose Timesetting No. 9).  While Timer 6 is timing, any subsequent activation by this detector will be ignored.
FAULT CONDITION
CANCELLING DETECTOR
If Detector 4 is alarmed:
-         Set a continuous MSS5 flag.
-         Turn on P1 Wait State and reset Special Counter 2 to zero.
XSF10 OVER-RIDE (of Special Counters 1 & 2)
If XSF10 is set.
-         Turn on P1 Wait State regardless of the Special Counters’ status. The most likely use for this flag will be if XSF2 (Detector 3) is disabled due to a detector alarm at Site 2413.
-         Reset Special Counters 1 & 2 to zero.
P1 WAIT STATE SUMMARY
The operation of P1 Wait State is impacted by both westbound and eastbound trams:
Turn ON P1 Wait State when ANY of the following are true:
·        Special Counter 1 is greater than zero
·        Special Counter 2 is greater than zero
·        XSF10 is set
·        Detector 1 is alarmed
·        Detector 2 is alarmed
·        Detector 4 is alarmed
Turn OFF P1 Wait State when ALL of the following are true:
·        Special Counters 1 and 2 both equal zero
·        XSF10 is not set
·        None of Detectors 1, 2 & 4 are alarmed