2 Product Specifications
GH17LS/GH17ES 2-3
QRS
P
O
Video
Sync Sync
Horizontal Vertical
CDE
P
O
B
A
Video
Sync Sync
Separate Sync
2-3 Timing Chart
This section of the service manual describes the timing that the computer industry recognizes as standard
for computer-generated video signals.
C D
AO
E
BP
Video
Sync Sync
Video
Q R S
A : Line time total B : Horizontal sync width O : Frame time total P : Vertical sync width
C : Back porch D : Active time Q : Back porch R : Active time
E : Front porch S : Front porch
VIDEO
A
BO
P
QRS
Horizontal Vertical
B
Green
Vertical
PQRS
O
Horizontal
H/V Composite Sync
Sync-on-Green
79.976
12.504
1.067
1.837
9.481
0.119
75.025
13.329
0.038
0.475
12.804
0.013
135.000
Positive
Positive
Separate
81.129
16.640
6.400
2.880
3.200
76.106
10.660
0.080
3.200
0.020
135.000
Negative
Negative
Com.
68.677
14.561
1.016
2.201
10.836
0.508
84.997
11.765
0.044
0.524
11.183
0.015
94.500
Positive
Positive
Separate
1024/85Hz
1024x768
1280/76Hz
1280x1024
1280/75Hz
1280x1024
1024/75Hz
1024 x 768
60.023
16.660
1.219
2.235
13.003
0.203
75.029
13.328
0.050
0.466
12.795
0.017
78.750
Positive
Positive
Separate
31.469
31.777
3.813
1.589
26.058
0.318
70.087
14.268
0.064
0.858
13.155
0.191
28.322
Negative
Positive
Separate
fH (kHz)
A µsec
B µsec
C µsec
D µsec
E µsec
fV (Hz)
O msec
P msec
Q msec
R msec
S msec
Clock
Freq.
(MHz)
Polarity
H.Sync
V.Sync
Remark
IBM
640/75 Hz
640 x 480
640/85 Hz
640 x 480
800/75 Hz
800 x 600
800/85 Hz
800 x 600
1024/60Hz
1024 x 768
VGA2/
70 Hz
720 x 400
VGA3/
60 Hz
640 x 480
Table 2-1. Timing Chart
31.469
31.778
3.813
1.589
26.058
0.318
59.940
16.683
0.064
0.794
15.761
0.064
25.175
Negative
Negative
Separate
37.500
26.667
2.032
3.810
20.317
0.508
75.000
13.333
0.080
0.427
12.800
0.027
31.500
Negative
Negative
Separate
43.269
23.111
1.556
2.222
17.778
1.556
85.008
11.764
0.671
0.578
11.093
0.023
49.500
Negative
Negative
Separate
46.875
21.333
1.616
3.232
16.162
0.323
75.000
13.333
0.064
0.448
12.800
0.021
49.500
Positive
Positive
Separate
53.674
18.631
1.138
2.702
14.222
0.569
85.061
11.756
0.056
0.503
11.179
0.019
56.250
Positive
Positive
Separate
48.363
20.677
2.092
2.462
15.754
0.369
60.004
16.666
0.124
0.600
15.880
0.062
75.000
Negative
Negative
Separate
Mode VESA
Timing (Analog Only) (Analog Only)