Service manual

APPENDIX A : PRESET TIMING CHART
Analog Mode
1 2 3 4 5 6 7
Signal name
symbol
TEXT
mode
TEXT
mode
VGA MAC-II VESA-VGA VESA-VGA VESA-VGA
H-frequency (kHz) 31.468 31.469 31.468 35.001 37.5 37.862 43.269
V-frequency (Hz)
70.087 70.087 59.941 66.667 75 72.807 85.005
Pixel rate (MHz)
25.175 28.322 25.175 30.240 31.5 31.501 36.000
H-sync Ths
96 108 96 64 64 40 56
H-back porch Thb
48 54 48 96 120 128 80
Count num (H-total) Thd
800 900 800 864 840 832 832
H- front porch Thf
16 18 16 64 16 24 56
V-sync Tvs
2 2 2 3 3 3 3
V-back porch Tvb
60 35 33 39 16 28 25
Count num (V-total) Tvd
449 449 525 525 500 520 509
V-front porch Tvf
37 12 10 3 1 9 1
H-sync. Polarity
Positive Negative Negative Negative Negative Negative Negative
V-sync Polarity
Negative Positive Negative Negative Negative Negative Negative
H-resolution (dots)
640 720 640 640 640 640 640
V-resolution (lines)
350 400 480 480 480 480 480
8 9 10 11 12 13 14
Signal name Symbol
IBM-8514
A
SVGA SVGA SVGA SVGA MAC 16" XGA
H-frequency (kHz) 35.156 37.879 48.077 46.875 53.674 49.725 48.363
V-frequency (Hz) 56.250 60.317 72.188 75.000 85.061 74.5 60.004
Pixel rate (MHz) 36.000 40.000 50.000 49.500 56.250 57.283 65.000
H-sync Ths 72 128 120 80 64 64 136
H-back porch Thb 128 88 64 160 152 224 160
Count num (H-total) Thd 1024 1056 1040 1056 1048 1152 1344
H- front porch Thf 24 40 56 16 32 32 24
V-sync Tvs 2 4 6 3 3 3 6
V-back porch Tvb 22 23 23 21 27 39 29
Count num (V-total) Tvd 625 628 666 625 631 667 806
V-front porch Tvf 1 1 37 1 1 1 3
H-sync. Polarity Negative Positive Positive Positive Positive Negative Negative
V-sync Polarity Negative Positive Positive Positive Positive Negative Negative
H-resolution (dots) 800 800 800 800 800 832 1024
V-resolution (lines) 600 600 600 600 600 624 768
9
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Do Not Copy VG910s/b