Changes
CRTC
,/* The 6845 Registers */
|1||Horizontal Displayed||00000000||40||Number of characters displayed. Once horizontal character count (HCC) matches this value, DISPTMG is set to 1.
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|2||Horizontal Sync Position (-1)||00000000||46||When to start the HSync signal.
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|3||Horizontal and Vertical Sync Widths||VVVVHHHH||128+14||HSync pulse width in characters (0 means 16 on some CRTC), should always be more than 8; VSync width in scan-lines. (0 means 16 on some CRTC. Not present on all CRTCs, fixed to 16 lines on these)
|6||Vertical Displayed||x0000000||25||Height of displayed screen in characters. Once vertical character count (VCC) matches this value, DISPTMG is set to 1.
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|7||Vertical Sync Position (-1)||x0000000||30||When to start the VSync signal, in characters.
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|8||Interlace and Skew||xxxxxx00||0||00: No interlace; 01: Interlace Sync Raster Scan Mode; 10: No Interlace; 11: Interlace Sync and Video Raster Scan Mode
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|9||Maximum Raster Address(-1)||xxx00000||7||Maximum scan line address on CPC can hold between 0 and 7, higher values' upper bits are ignored
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|10||Cursor Start Raster||xBP00000||0||Cursor not used on CPC. B = Blink On/Off; P = Blink Period Control (Slow/Fast). Sets first raster row of character that cursor is on to invert.
