Talk:PPU rendering
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0=blank vs. 0=active
There are two different conventions:
| 0=active | 0=blanking | Description |
|---|---|---|
| 261 or -1 | 20 | Pre-render scanline |
| 0-239 | 21-260 | Active picture |
| 240 | 261 | Post-render scanline |
| 241-260 | 0-19 | Vertical blanking |
You're using the 0=blanking convention. But more often on the BBS and elsewhere on this wiki, I've seen 0=active. The PPU power up state appears to agree with 0=active, as do the (X, Y) coordinate displays in the debugger of FCEUX and Nintendulator and the VCOUNT register on the Game Boy ($FF44) and Game Boy Advance ($04000006). The 0=active convention makes it easier to consolidate discussion of NTSC, PAL, and PAL clone timing as well. --Tepples 20:15, 3 April 2011 (UTC)
