VCT 38xxA
ADVANCE INFORMATION
FP Display Control Register, Vertical Sawtooth
DC offset of SAWTOOTH output
h’110
0
OFS
This offset is independent of EHT compensation.
h’11b
h’11c
h’11d
h’11e
accu0 init value
accu1 init value
accu2 init value
accu3 init value
−1365 A0
900 A1
0
0
A2
A3
FP Display Control Register, East-West Parabola
h’12b
h’12c
h’12d
h’12e
h’12f
accu0 init value
accu1 init value
accu2 init value
accu3 init value
accu4 init value
−1121 A0
219 A1
479 A2
−1416 A3
1052 A4
2.15.1.2. Calculation of Vertical and East-West
Deflection Coefficients
Vertical Deflection 60 Hz
a
b
–1365.3
1083.5
c
+682.7
–1090.2
429.9
d
–682.7
In Table 2–8 the formula for the calculation of the
deflection initialization parameters from the polynomi-
nal coefficients a,b,c,d,e is given for the vertical and
East-West deflection. Let the polynomial be:
a0
a1
a2
a3
128
+1645.5
–1305.8
1023.5
P = a + b(x – 0.5) + c(x – 0.5)2 + d(x – 0.5)3 + e(x – 0.5)4
The initialization values for the accumulators a0..a3 for
vertical deflection and a0..a4 for East-West deflection
are 12-bit values. The coefficients that should be used
to calculate the initialization values for different field
frequencies are given below, the values must be
scaled by 128, i.e. the value for a0 of the 50 Hz vertical
deflection is:
East-West Deflection 50 Hz
a
b
–341.3
111.9
c
1365.3
–899.6
586.8
d
–85.3
84.8
e
341.3
a0
a1
a2
a3
a4
128
–454.5
898.3
a0 = (a · 128 – b · 1365.3 + c · 682.7 – d · 682.7) / 128
–111.1
72.1
–1171.7
756.5
Table 2–8: Calculation of Initialization values for
Vertical Sawtooth and East-West Parabola
East-West Deflection 60 Hz
Vertical Deflection 50 Hz
a
b
–341.3
134.6
c
1365.3
–1083.5
849.3
d
–85.3
102.2
–161.2
125.6
e
341.3
a
b
–1365.3
899.6
c
+682.7
–904.3
296.4
d
–682.7
+1363.4
–898.4
585.9
a0
a1
a2
a3
a4
128
a0
a1
a2
a3
128
–548.4
1305.5
–2046.6
1584.8
46
Micronas
MICRONAS [ MICRONAS ]
