Changes

=== Overflow during HSYNC HSC (C3l) overflow ===

During an HSYNC, if HSYNC Width (R3l) is changed with a value less than the current HSC, then HSC is overflowingoverflows and will continue to count up to its maximum value (15) before looping.  The only exception is for CRTC 1 with a value of 0, which cancels the current HSYNC. <br> === VLC (C9) overflow === If Number of Scan Lines (R9) is updated with a value less than the current VLC, then:* on CRTCs 0/1/2, VLC overflows and will count up to its maximum value (31) before looping* on CRTCs 3/4, the current line is considered the last one of this CRTC character and VLC changes to 0 on the next line <br> === VTAC overflow === During vertical adjustment mode, if Vertical Total Adjust (R5) is changed with a value less than the current VTAC, then:* on CRTCs 0/1/2, VTAC overflows and will continue to count up to its maximum value (31) before looping* on CRTCs 3/4, the current line is considered the last one of the current frame and vertical adjustment ends

=== Overflow during Vertical Adjustment VCC (C4) overflow ===

During vertical adjustmentOn all CRTCs, if Vertical Total Adjust (R5R4) is changed updated with a value less than the current VTAC, thenVCC:* on CRTCs 0/1/2if this update was done when VLC < R4, VTAC then VCC overflows and continues will continue to count up to 0 to reach new R5 its maximum value(127) before looping* on CRTC 3/4if this update was done when VLC >= R4, the line is considered the last decision has already been made to switch to vertical adjustment or vertical border mode and additional management endsno update to R4 will make the CRTC change its mind for the current frame