Changes

1,053 bytes added ,  08:07, 24 February 2021
Document interlacing and line doubling properly
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| 5
 
| 5
| Enable parallax barrier (i.e. 3D).
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| Interlacing enable (interleaves framebuffers A and B; used by top screen in 3D mode)
 
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|-
 
| 6
 
| 6
| 1 = main screen, 0 = sub screen. However if bit5 is set, this bit is cleared.
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| Line doubling enable (used by top screen in 2D mode)
 
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|-
 
| 7
 
| 7
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GSP module only allows the LCD stereoscopy to be enabled when bit5=1 and bit6=0 here. When GSP module updates this register, GSP module will automatically disable the stereoscopy if those bits are not set for enabling stereoscopy.
 
GSP module only allows the LCD stereoscopy to be enabled when bit5=1 and bit6=0 here. When GSP module updates this register, GSP module will automatically disable the stereoscopy if those bits are not set for enabling stereoscopy.
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When both interlacing and line doubling are disabled, the full resolution of the top screen (240x800) can be utilized if the PDC registers are updated to accomodate this higher resolution. GSP contains tables for this mode (gsp mode == 1). GSP automatically applies this mode if both bit5 and bit6 are cleared. This is also the default, and the only valid mode for the bottom screen.
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If only interlacing is enabled, gsp detects this as a request to switch to 3D mode (gsp mode == 2), and enables the parallax barrier.
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It's unknown how to control this, but some other PDC registers control if interlacing should be done by true interleaving (both framebuffers are treated as 240x400), or skipping lines (both framebuffers are treated as 240x800)
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If only line doubling is enabled, gsp detects it as a request to switch back to 2D mode for the top screen (gsp mode == 0). This is also the default mode for the top screen.
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Both interlacing and line doubling can't be enabled in usermode, but it works as expected in baremetal.
    
=== Framebuffer color formats ===
 
=== Framebuffer color formats ===
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