Welch Allyn Grason-Stadler GSI 17 Series - General Operation of Controls; Power up Initialization

2.2 REAR PANEL CONNECTORS AND INDICATORS
R1 -
Power input jack with front panel
indication of
position
and rear panel indication of input
power
specifications.
R2
- Attention,consult accompanying documents.
R3
- Earphone output jacks with front panel
indication
of left and right phone provided by illustration of
subject.
R4 -
Subject response switch input jack with front panel
indication of position.
R5
- Calibration switch indication.
2.3 GENERAL OPERATION OF CONTROLS
All controls are valid at
all times
once
the
power up
initialization is complete,
except for special cases as indicated
in this document and for the Extended Range
Pushbutton
which
depends on the HL selection. When the Extended Range is
invalid
there will be no indication given to the operator other than
the
absence of the "+" LCD segment.
All polled
controls are checked every 12 msec for a
change in
state. All operations of all controls are debounced for 12
msec
before processing.
The Extended
Range pushbutton operates by a push ON,
push OFF
manner. The Present Bar and Response Switch operate
by a
press
and hold manner (except in the Calibration and Diagnostic modes
where the Present Bar is push ON, push OFF).
When a press and hold type control is operated all other controls
are still active.
When the operation of a control is being processed the processing
of all other controls is delayed until the first operation is
completed.
2.4 POWER UP INITIALIZATION
When
the power switch is set to the ON position
the
instrument
will go through the following initialization process:
All internal and external
hardware
components of
the
microprocessor
system will be initialized for the
required
type of operation.
All
LEDs and LCD segments will be turned on to indicate that
the power up initialization is in progress.