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Rev Author Line No. Line
1058 lvd 1
::video mode from baseconf::
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60hz TV: positive polarity both,
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hsync period  1792
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hsync on time 132
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vsync period  469504 (262 lines)
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vsync on time 3896, begins with hsync
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hblank begins 40 clocks before hsync, ends 180 clocks after (zeros on output)
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vblank begins 4 hsync periods before vsync, ends 16 hsync periods after end of vsync
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60hz VGA: positive polarity both,
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hsync period  896
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hsync on time 106
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vsync period  469504 (524 lines)
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vsync on time 3896, begins next clock after hsync
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hblank begins 18 clocks before hsync
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hblank ends 52 clocks after hsync
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1059 lvd 22
=================================================
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font format: 6x6, 2 EABs, format as defined in mkfont.py
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frame buffer format: 8 EABS, 4096 bytes.
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overall:
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 60x40 chars
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chars:
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 placed compact in memory, total 60x40 = 2400 (0x960) bytes, each line is 60 bytes long
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 start offset = 0
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 charcodes allowed: 32..255
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attrs:
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 5 bits per attr, packed compactly in sequential bytes:
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bytes: b7 b6 b5 b4 b3 b2 b1 b0 | b7 b6 b5 b4 b3 b2 b1 b0 | b7 b6 b5 b4 b3 b2 b1 b0 | b7 b6 b5 b4 b3 b2 b1 b0 | b7 b6 b5 b4 b3 b2 b1 b0 |
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attrs: a4 a3 a2 a1 a0                  a4 a3 a2 a1 a0                  a4 a3 a2 a1   a0                a4 a3   a2 a1 a0
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                      a4 a3 a2   a1 a0                a4   a3 a2 a1 a0                  a4 a3 a2 a1 a0                  a4 a3 a2 a1 a0
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 each line has a size of 40 bytes in memory, only first 60 attrs (out of total 64) are used.
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 each line starts from left-aligned attr as in picture above
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 total 40*40 = 1600 (0x640) bytes
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 start offset = 0x9C0
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 attr format:
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 a4 a3 a2 a1 a0
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 b1 b0 p2 p1 p0
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 {b1,b0} == background color
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 {p2,p1,p0} == character color
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