public DMAChannel(ARM7TDMI cpu, int index)
{
this.DMACNT_H = new cDMACNT_H(this, index == 3);
this.DMACNT_L = new cDMACNT_L(cpu.bus, (ushort)(index == 3 ? 0xffff : 0x3fff));
this.DMASAD = new cDMAAddress(cpu.bus, index == 0);
this.DMADAD = new cDMAAddress(cpu.bus, index != 3);
this.cpu = cpu;
this.IF = cpu.IO.IF;
this.index = index;
this.Sound = index == 1 || index == 2;
}
private void UpdateDMAAddress(cDMAAddress dmaxad, AddrControl control)
{
uint amount = (uint)(this.DMACNT_H.DMATransferType ? 4 : 2);
switch (control)
{
case AddrControl.IncrementReload: // 11 (prohibited for DMASAD)
case AddrControl.Increment: // 00
dmaxad.Address += amount;
break;
case AddrControl.Decrement: // 01
dmaxad.Address -= amount;
break;
case AddrControl.Fixed: // 10
break;
}
}
