Changes
CRTC
,/* Interlace and Skew (R8) */
On all CRTCs, in both interlace modes, an additional line (the 625th line) is added automatically by the CRTC at the end of the even field.
For a CRTC character line of with n raster lines, R9 must be set to n-1 on all CRTCs, regardless of the interlace settings. The exception is for CRTCs 0/3/4 in IVM mode, where R9 must be set to n-2.
==== Interlace sync mode (ISM) ====
