hmove

Documentation

Overview

Package hmove represents the TIA HMOVE process.

Index

• type Hmove
  • func (hm *Hmove) Reset()
  • func (hm *Hmove) ResetRipple()
  • func (hm *Hmove) String() string
  • func (hm *Hmove) Tick()

Types

type Hmove

type Hmove struct {
	// the delay between HMOVE being triggered and the latch flag being set
	// to true
	FutureLatch delay.Event

	// Latch indicates whether HMOVE has been triggered this scanline. it is
	// reset when a new scanline begins
	Latch bool

	// the delay between HMOVE being triggered and the ripple count starting
	Future delay.Event

	// Ripple counts backwards from 15 to -1 (represented by 255). note that
	// unlike how it is described in TIA_HW_Notes.txt, we always send the extra
	// tick to the sprites on Phi1.  however, we also send the HmoveCt value,
	// whether or not the extra should be honoured is up to the sprite.
	// (TIA_HW_Notes.txt says that HmoveCt is checked *before* sending the
	// extra tick)
	Ripple uint8

	// Has the Ripple counter just expired this cycle
	RippleJustEnded bool

	// Clk is true when the TIA PhaseClock.Phi2() is true
	Clk bool
}

func (*Hmove) Reset

func (hm *Hmove) Reset()

Reset Hmove values.

func (*Hmove) ResetRipple

func (hm *Hmove) ResetRipple()

ResetRipple begins the ripple count.

func (*Hmove) String

func (hm *Hmove) String() string

func (*Hmove) Tick

func (hm *Hmove) Tick()

Tick every video cycle when Clk is true. ie. when the TIA phaseclock is in rising Phi2.