Timing parameters rule

[ToastyX]

The rules depend on the standards, but the tearing problem is a monitor-specific limitation, so the rules might not matter. CRU includes all the common standards.

• For VESA standards, the horizontal values are multiples of 8.
• For CVT-RB, the horizontal values are always 48 32 80, and for CVT-RB2, the horizontal values are always 8 32 40.
• For CVT/CVT-RB, the vertical front porch is always 3, the vertical sync width is based on the aspect ratio (5 for 16:9), and the vertical back porch is set to make the vertical blanking at least 460 microseconds.
• For CVT-RB2, the vertical sync width is always 8, the vertical back porch is always 6, and the vertical front porch is set to make the vertical blanking at least 460 microseconds.
• For CTA-861, 1920x1080 @ 30/60/120 Hz is 88 44 148 for horizontal and 4 5 36 for vertical.