A/D Converter Diagnostic Test ( D 3 ) - Welch Allyn Grason-Stadler GSI 17 Series Service Manual

4.9.4 A/D CONVERTER DIAGNOSTIC TEST (D3)
TEST DESCRIPTION
This test will provide a means to test the A/D converter
used to measure the battery voltage.
the A/D input will be sampled every msec and the converted
displayed on the HL display.
During this test the low battery voltage monitoring will not be
performed since the A/D converter is not available to measure the
battery voltage.
TEST INITIALIZATION
When switched
instrument will be initialized as follows:
Tone Type = Current selection
Frequency = Current selection
Stimulus M
Channel = OFF
Attenuator Position = 255
+10 dB Pad = Out
Transducer Routing = None
HL Display = Displays "D1" for 2 seconds and then blanks
Response LED = OFF
Stimulus On LED = OFF
Low Battery Segment = Current State
DESCRIPTION OF CONTROLS
controls except the Cal/Normal switch
All
Pushbutton are inactive during this diagnostic test.
of all other controls will be ignored.
EXTENDED RANGE PUSHBUTTON
This pushbutton is used to store the A/D values in the EEPROM for
"LO Bat" detection
"shutdown" will
safely operate the GSI 17 circuitry.
When the Extended Range Pushbutton is pressed the first time, the
A/D value is
The Patient Response LED will be turned ON and "L1" will
EEPROM.
be displayed on
previously displayed
value can not be stored properly, the word "CAL" will be
on the HL display and the previously displayed value will be
restored. The A/D value for battery low warning limit must be
stored successfully before allowing the next press of Extended
Range Pushbutton to store the battery shutdown limit.
A/D value is stored properly the EEPROM checksum will be updated.
into the A/D
= Current position
UX
and
instrument
occur when the battery voltage is
stored as the battery low warning
HL display
the
A/D value will be restored.
When this test is
Converter diagnostic
and
"shutdown".
for 2 seconds.
channel
selected
value
test,
the
Extended Range
Operations
Instrument
too low to
limit in the
Then the
If the
A/D
flashed
After the