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0 users reading the writable VCount shit | 1 bot

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Arisotura
Posted on 05-05-17 04:44 PM (rev. 2 of 05-05-17 04:54 PM) Link | #144
finding dump


* writing to VCOUNT (val < current) makes the frame last longer
* VCOUNT write is applied at the next scanline
* VCOUNT can be written during display (!!)
** doing so screws up display: the 2D GPU uses the new VCOUNT value, but the LCDs keep going from the old value
** I don't want to imagine what that does to the 3D GPU or HDMA
** and it can likely cause VBlank/VMatch IRQs to trigger again
** the GPU can't go past scanline 191 (if you abuse VCOUNT write to make it skip forward) -- further scanlines are filled white

* it's writable from either CPU

____________________
Kuribo64


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