=== Vertical Adjustment mode ===
On CRTCs 03/1/24, this mode increments does not increment VCC and , so VCC goes beyond remains equal to R4.
On CRTC 0, this mode increments VCC, causing it to exceed R4, but this increment occurs only once. On CRTCs 31/42, this mode does not increment increments VCC and so VCC stays equal , causing it to exceed R4, and this increment can happen multiple times depending on the values of R5 and R9. Also, only CRTCs 1/2 have a dedicated C5 counter. On CRTCs 0/3/4, during Vertical Adjustment, C9 has to fullfil the VTAC role which means that it cannot fullfil its VLC role. This impacts address generation as R9 is not considered anymore.
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