Struct R2C02::registers_t

Nested Relationships

This struct is a nested type of Class R2C02.

Struct Documentation

struct registers_t

“Public” registers accessible by the CPU.

Public Members

uint8_t nameX

Base nametable address, scroll X coordinate MSB. (1 = add 256)

uint8_t nameY

Base nametable address, scroll Y coordinate MSB. (1 = add 240)

uint8_t incMode

VRAM address increment per CPU R/W of PPUDATA. (0 = add 1, 1 = add 32).

uint8_t spriteAddress

Sprite pattern table address for 8x8 sprites.

uint8_t backgroundAddress

Background pattern table address.

uint8_t spriteSize

Sprite size (8x8, 8x16).

uint8_t masterSlave

PPU master/slave.

uint8_t nmi

Generate NMI on vblank.

struct R2C02::registers_t::[anonymous]::[anonymous] bits
uint8_t data
union R2C02::registers_t::[anonymous] ppuctrl

Controller (0x2000) - PPUCTRL Access: write Controls PPU operation.

uint8_t grayscale

Enable grayscale.

uint8_t showBackgroundLeft

Show background in leftmost 8 pixels.

uint8_t showSpritesLeft

Show sprites in leftmost 8 pixels.

uint8_t showBackground

Show bg.

uint8_t showSprites

Show sprites.

uint8_t eRed

Enhance red. (Green on PAL/Dendy.)

uint8_t eGreen

Enhance green. (Red on PAL/Dendy.)

uint8_t eBlue

Enhance blue.

struct R2C02::registers_t::[anonymous]::[anonymous] bits
union R2C02::registers_t::[anonymous] ppumask

Mask register (0x2001) - PPUMASK Access: write Controls the rendering of sprites and backgrounds and color effects.

uint8_t padding

Least sig. bits of previous value written to PPU register. Some Vs. systems return a constant that game checks.

uint8_t spriteOverflow

Buggy detection of the existence of more than 8 sprites on a scanline.

uint8_t spriteZeroHit

Nonzero pixel of sprite 0 overlaps nonzero background.

uint8_t vBlank

True if vblank started, cleared after reading this register.

struct R2C02::registers_t::[anonymous]::[anonymous] bits
union R2C02::registers_t::[anonymous] ppustatus

Status register (0x2002) - PPUSTATUS Access: read Reflects the state of the PPU.

uint8_t byte
uint8_t index
struct R2C02::registers_t::[anonymous]::[anonymous] bits
union R2C02::registers_t::[anonymous] oamAddress