DESCRIPTION AND OPERATION
BUS FAULT TIMER
WBPEEUI240754A0
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BUS FAULT TIMER
The bus fault timer is a one-shot timer that is reset by the I/O
expander bus clock; the control module generates the bus
clock. If the clock stops (indicating a control module error or
failure), the bus fault timer times out in 10 milliseconds. This
causes the digital outputs to change to their default values. A
red front panel status LED indicates a bus fault (time-out).
STATUS LED INDICATOR
Two front panel module status LED indicators show the oper-
ating state of the DSO. Circuits on the DSO determine the
module status and light the LED accordingly.
in Section 4 describes the LED indications and
in Section 5 provides corrective actions
to take.
