Difference between revisions of "Video Timing Register"

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Each VGA setting increases the frequency by approximately 1 kHz.  
 
Each VGA setting increases the frequency by approximately 1 kHz.  
  
Experimental results based on what one vga monitor reports:
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Experimental results based on "Vibrant VL5A9DL" vga monitor reports:
  
 
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Latest revision as of 11:05, 26 May 2020

Number $11
Readable Yes
Writable Yes
Short Description Sets video output timing variant.

(writable in config mode only)

Bit Function
7-3 Reserved, must be 0
2-0 video signal timing variant

Possible timing variants:

Bit pattern selected variant
%000 Base VGA timing, clk28 = 28000000
%001 VGA setting 1, clk28 = 28571429
%010 VGA setting 2, clk28 = 29464286
%011 VGA setting 3, clk28 = 30000000
%100 VGA setting 4, clk28 = 31000000
%101 VGA setting 5, clk28 = 32000000
%110 VGA setting 6, clk28 = 33000000
%111 HDMI, clk28 = 27000000

Each VGA setting increases the frequency by approximately 1 kHz.

Experimental results based on "Vibrant VL5A9DL" vga monitor reports:

mode 50hz 60hz
vga0 49.3 58.1
vga1 50.3 59.3
vga2 51.9 61.1
vga3 52.8 62.2
vga4 54.6 64.3
vga5 56.4 66.4
vga6 58.1 68.5

50/60Hz depending on bit 2 of Peripheral 1 Register ($05).