4-12
6.5 Reference Signal Timing
Item
Abbreviation
VESA 1280x1024 75Hz
VESA 640x480 75Hz
Pixel frequency
fc
135.00MHz
31.500MHz
Horizontal frequency
fh
79.98kHz
37.50kHz
Line Time total
Th
12.50us
1688CLK
26.67us
840CLK
Horizontal active display
Thd
9.48us
1280CLK
20.32us
640CLK
Horizontal sync pulse
Thp
1.07us
144CLK
2.03us
64CLK
Horizontal back porch
Thb
1.84us
248CLK
3.81us
120CLK
Horizontal front porch
Thf
0.12us
16CLK
0.51us
16CLK
Horizontal sync polarity
POS
NEG
Vertical Frequency
fv
75.03Hz
75.00Hz
Frame time total
Tv
13.33ms
1066H
13.33ms
500H
Vertical active display
Tvd
12.80ms
1024H
12.80ms
480H
Vertical sync pulse
Tvp
0.04ms
3H
0.08ms
3H
Vertical back porch
Tvb
0.48us
38H
0.43ms
16H
Vertical front porch
Tvf
0.01ms
1H
0.03ms
1H
Vertical sync polarity
POS
NEG