Changes
CRTC
,/* Counter freezes */
* VLC Freeze: Because HCC never reaches 1, the logic that increments VLC is never triggered. VLC freezes at the value it held before R0 was set to 0.
* VCC's Last Hiccup: If VLC equals R9 and VCC equals R4 at the exact instant R0 becomes 0, VCC increments once on the very next HCC=0. After this, VCC freezes.
* Vertical Adjustment: If both VLC=R9 and VCC=R4 at the instant R0 is set to 0, vertical adjustment is activatedstarts. This continues even after R0 changes to > 1. Here, VCC increments only once and then freezes.
* Register Update Freeze: Updates to R4, R5, and R9 are ignored while R0=0. However, R8 is still evaluated at each HCC=0.
When R0=1:
* VLC Management: VLC increments and R9 updates are considered once per line (when HCC=0).
* Vertical Adjustment: If both VLC=R9 and VCC=R4 while HCC is 0 or 1are true when evaluated during the first 3 cycles of the line, vertical adjustment starts. It ends when VLC, calculated for the next line, equals R5.
* Register Update: R4, R5, and R9 updates are considered only when HCC=0. R8 is evaluated at each HCC=0.
