U511
Timer
TMRO
SQWIN
TMR1 SCFCLK
TMR2
CLKGEN
OUT
8254 Counter 0 Used for
the Oscillator SWQIN
OUT Clock.
Frequency =
Stimulus Frequency 8254
OUT
Counter 1 Used for the
Oscillator Switched
Capacitor Filter SCFCLK.
(see the following table
8254 Counter 2 Used to
Produce the 2
msec
Time-
base.
SWITCHED CAPACITOR FILTER CONTROLS
Front
Filter
Panel/
Cutoff
Freq
Freq
Switched
Capacitor
SCFCLK (Clock)
Freq
Timer
50/100
Setting
State
125
150.38
15,038
266.00
0
250
300.75
30,075
133.00
0
500
606.06 60,606
66.00
0
750 909.09 90,909
44.00
0
1000 1176.47 117,647 34.00
0
1500 1818.18
181,818
22.00
0
2000 2500.00
250,000
16.00
0
3000 3333.33
333,333
12.00
0
4000 5000.00
250,000
16.00
1
6000
8000.00 400,000
10.00
1
8000 8000.00
400,000
10.00
1
Signal
Name Direction Description
Antialiasing
AAFIL
BP/
State
LP
0
0
0
0
0
0
0
0
1
0
1
0
-1
0
1
0
1
0
1
0
1
1
8.7 DISPLAY (LCD)
The LCD is a reflective
3-1/2
digit Liquid Crystal Display. It
is the largest indicator on the GSI 17, and it is used for a
variety of purposes.
Some purposes are:
indication of HL and
possible error messages in the Normal Mode, along with SPL and
A/D numbers in the calibration and Diagnostic Modes.
(Refer to
each mode's functional description for detail).
An LCD segment is energized only when there is a 5 Volt potential
across it.
To confirm if a segment is receiving the
appropriate
drive signal,
connect
CH1
of an oscilloscope to
the
backplane
signal and CH2 to the segment drive signal.
For an
"ON"
segment
the
signals should be out of phase, therefore applying
5 Volts
across it.
6666
To Next Page
Loading...
