![]() ![]() games as a copy protection measure.īoth have been used in RGB mods for the NES, as a circuit implementing A0' = A0 xor (A1 nor A2) can swap PPUCTRL and PPUMASK to make a 2C05 behave as a 2C03. Tennis, all Pla圜hoice games, the Famicom Titler, and the Famicom TV. This palette is intentionally similar to the NES's standard palette, but notably is missing the greys in entries $2D and $3D. The PAL PPU (2C07) has a 15 degree hue shift relative to NTSC. These simulate generating a large area of one flat color and then decoding that with the adjustment knobs set to various settings. Other tools for generating a palette include one by Bisqwit and one by Drag. pal format, in which each triplet represents the sRGB color that results from decoding a large flat area with a given palette value. Most emulators can use a predefined palette, such as one commonly stored in common. Instead it generates NTSC video directly in the composite domain, decoded by the television receiver into RGB to drive its picture tube. Unlike some other consoles' video circuits, the 2C02 does not generate RGB video and then encode that to composite. The RF Famicom, AV Famicom, NES (both front- and top-loading), and the North American version of the Sharp Nintendo TV use the 2C02 PPU. NES palette generated with Bisqwit's tool System, Playchoice 10), as well as the Sharp Famicom Titler. RGB PPUs were used mostly in arcade machines (e.g. The look-up tables (one digit for each of red, green, and blue, in order) are given below. The sync signal contains horizontal and vertical sync pulses in the same format as an all-black composite signal.Įach of the three video channels uses a 3-bit DAC driven by a look-up table in a 64x9-bit ROM inside the PPU. The 2C03, 2C04, and 2C05, on the other hand, all output analog red, green, blue, and sync (RGBS) signals. The 2C02 (NTSC) and 2C07 (PAL) PPU is used to generate an analog composite video signal. System arcade games have completely different palettes as a copy protection measure. The 2C03 RGB PPU used in the Pla圜hoice-10 and Famicom Titler renders hue $D as black, not dark gray. It results in a "blacker than black" signal that may cause problems for some TVs. The canonical code for "black" is $0F or $1D.ĭo not use color $0D. For details, see NTSC video, or for a list see Color $0D games. It works this way because of the way colors are represented in an NTSC or PAL signal, with the phase of a color subcarrier controlling the hue. Hue $0 is light gray, $1-$C are blue to red to green to cyan, $D is dark gray, and $E-$F are mirrors of $1D (black). ||++- Value (voltage, determines NTSC/PAL luma) ||||++++- Hue (phase, determines NTSC/PAL chroma) |++- Palette number from attribute table or OAMĪs in some second-generation game consoles, values in the NES palette are based on hue and brightness: Thus, indices into the palette are formed as follows: Note that this goes for writing as well as reading.Ī symptom of not having implemented this correctly in an emulator is the sky being black in Super Mario Bros., which writes the backdrop color through $3F10. They can still be shown using the background palette hack, explained below.Īddresses $3F10/$3F14/$3F18/$3F1C are mirrors of $3F00/$3F04/$3F08/$3F0C. The choice of palette is in attribute 2 of each sprite (see PPU OAM).Īddresses $3F04/$3F08/$3F0C can contain unique data, though these values are not used by the PPU when normally rendering (since the pattern values that would otherwise select those cells select the backdrop color instead). ![]() The choice of palette for each 16x16 pixel area is controlled by bits in the attribute table at the end of each nametable.Įach sprite can use the three colors from one of the sprite palettes. Each color takes up one byte.Įach 16x16 pixel area of the background can use the backdrop color and the three colors from one of the four background palettes. The palette for the background runs from VRAM $3F00 to $3F0F the palette for the sprites runs from $3F10 to $3F1F. ![]() 3 Backdrop color (palette index 0) uses.2.3.6 Games compatible with multiple different PPUs. ![]()
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