/// <summary>
/// Tries to execute the interrupt.
/// </summary>
/// <param name="interrupt">The interrupt.</param>
/// <param name="address">The address.</param>
/// <returns></returns>
private bool TryExecuteInterrupt(InterruptFlag interrupt, ushort address)
{
if (!_interruptFlag.HasFlag(interrupt) || !_interruptEnableRegister.InterruptEnabled(interrupt))
{
// Interrupt flag is not set or enabled.
return(false);
}
// Do interrupt.
_interruptManager.Interrupt(address);
// Clear the interrupt flag.
_interruptFlag &= ~interrupt;
return(true);
}
/// <summary>
/// Updates the interrupt flags, setting any new interrupt flags in <see cref="interrupts" />.
/// </summary>
/// <param name="interrupts">The interrupts.</param>
public void UpdateInterrupts(InterruptFlag interrupts)
{
// Combine with delayed interrupts.
_interruptFlag |= interrupts;
if (_interruptFlag == InterruptFlag.None)
{
return;
}
if (!_interruptManager.InterruptsEnabled)
{
// Interrupts disabled.
return;
}
if (TryExecuteInterrupt(InterruptFlag.VerticalBlank, VerticalBlankAddress))
{
return;
}
if (TryExecuteInterrupt(InterruptFlag.LcdStatusTriggers, LcdStatusTriggersAddress))
{
return;
}
if (TryExecuteInterrupt(InterruptFlag.TimerOverflow, TimerOverflowAddress))
{
return;
}
if (TryExecuteInterrupt(InterruptFlag.SerialLink, SerialLinkAddress))
{
return;
}
TryExecuteInterrupt(InterruptFlag.JoyPadPress, JoyPadPressAddress);
}
/// <summary>
/// Initializes a new instance of the <see cref="InterruptEnableRegister"/> class.
/// </summary>
public InterruptEnableRegister()
{
_interruptFlag = InterruptFlag.None;
}
/// <summary> /// Gets a value indication whether interrupts are enabled for the specific interrupt flag. /// </summary> /// <param name="flag">The flag.</param> /// <returns></returns> public bool InterruptEnabled(InterruptFlag flag) => _interruptFlag.HasFlag(flag);
/// <summary>
/// Initializes a new instance of the <see cref="InterruptFlagsRegister"/> class.
/// </summary>
/// <param name="interruptManager">The interrupt manager.</param>
/// <param name="interruptEnableRegister">The interrupt enable register.</param>
public InterruptFlagsRegister(IInterruptManager interruptManager, IInterruptEnableRegister interruptEnableRegister)
{
_interruptManager = interruptManager;
_interruptEnableRegister = interruptEnableRegister;
_interruptFlag = InterruptFlag.None;
}
