Integrated Functions (Continued)
Table 4-27. CRT Display Modes (Note 1)
DCLK Rate
(MHz)
(Note 2)
PCLK Rate
(MHz)
(Note 3)
Simultaneous
Colors
Refresh Rate
(Hz)
Resolution
640x480
8-bpp
256 colors out of a
palette of 256
60
72
75
85
60
72
75
85
60
72
75
85
60
72
75
85
60
70
75
85
60
70
75
85
60
75
50.35
63.0
63.0
72.0
50.35
63.0
63.0
72.0
80.0
100.0
99.0
112.5
80.0
100.0
99
25.175
31.5
31.5
36.0
25.175
31.5
31.5
36.0
40.0
50.0
49.5
56.25
40.0
50.0
49.9
56.25
65.0
75.0
78.5
94.5
65.0
75.0
78.5
94.5
108.0
135
16-bpp
64 KB colors
RGB 5-6-5
800x600
8-bpp
256 colors out of a
palette of 256
16-bpp
64 KB colors
RGB 5-6-5
112.5
65.0
75.0
78.5
94.5
65.0
75.0
78.5
94.5
108.0
135.0
1024x768
8-bpp
256 colors out of a
palette of 256
16-bpp
64 KB colors
RGB 5-6-5
1280x1024
8-bpp
256 colors out of a
palette of 256
Notes: 1. This list is not meant to be an complete list of all the possible supported CRT display modes.
2. DCLK is the input clock from the Geode I/O companion. In some cases, DCLK is doubled to keep the
Geode I/O companion’s PLL in a desired operational range.
3. PCLK is the graphics output clock to the Geode I/O companion.
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