Specifications

Engineering Standard –NSW
Signalling SMS 02
Cerberus Level Crossing Monitor Equipment
March 2005 Version 1.2 © Australian Rail Track Corporation Page 88 of 118
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y is a Boolean expression as described
previously. 7.1.2.9 Timer expression
A timer variable becomes TRUE when the expression that drives the
timer has been TRUE for the length of time that the timer is set for.
The timer variable becomes FALSE immediately that its expression
becomes FALSE.
Timer expressions have the following format:
x =T Ah B m Cs y
where
x is a internal variable which was declared in the IO list as a
Timer. =T identifies that it is a Timer expression.