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//
// Initialize DMA for write / read access
//
BOOLEAN DmaInitialize(DWORD Address, 
                 BYTE Channel,
                 DWORD Mode,
                 WORD Size)
{
   _asm cli

   if (Channel == DMA_CHANNEL_FLOPPY)
   {
      WRITE_PORT_UCHAR(0x0A, 0x06);
   }
   else
   {
      _asm sti
      return FALSE;
   }

   //
   // Reset Flip-Flop
   //

   WRITE_PORT_UCHAR(0x0c, 0);

   //
   // Transfer memory to device
   //
   if (Mode == DMA_MODE_READ)
   {
      if (Channel == DMA_CHANNEL_FLOPPY)
      {
         WRITE_PORT_UCHAR(0x0b, 0x5a);
      }
   }
   //
   // Transfer device to memory
   //
   else if(Mode == DMA_MODE_WRITE)
   {
      if (Channel == DMA_CHANNEL_FLOPPY)
      {
         WRITE_PORT_UCHAR(0x0b, 0x56);
      }
   }

   
   //
   // Set the memory page
   //
   WRITE_PORT_UCHAR(0x81, Address >> 16);

   //
   // Set low byte of the offset
   //
   WRITE_PORT_UCHAR(0x04, (Address & 0xffff) & 0xFF);

   //
   // Set high byte of the offset
   //
   WRITE_PORT_UCHAR(0x04, (Address & 0xffff) >> 8);

   //
   // Set low byte of the size
   //
   WRITE_PORT_UCHAR(0x05, Size & 0xff);

   //
   // Set high byte of the offset
   //
   WRITE_PORT_UCHAR(0x05, Size >> 8);

   //
   // Clear channel mask
   //
   if (Channel == DMA_CHANNEL_FLOPPY)
   {
      WRITE_PORT_UCHAR(0x0a, 2);
   }

   _asm sti
   return TRUE;
}



BOOLEAN FdcIsReady()
{
   //
   // read from main status register
   //
   BYTE State = READ_PORT_UCHAR(FDC_MSR);

   //
   // if data register ready
   //
   if ( (State & 0xc0) == 0x80 )
      return TRUE;
   else
      return FALSE;
}

//
// Stops the system till floppy is ready
//
VOID FdcWaitForReady()
{
   while (TRUE)
   {
      if (FdcIsReady())
         break;
   }
}


VOID FdcReadSector(BYTE Sector, BYTE Track, BYTE Head)
{
   BYTE Command[9];

   WRITE_PORT_UCHAR(FDC_DOR, 0x1c);
   Command[0] = 0x46;
   Command[1] = 0;
   Command[2] = Track;
   Command[3] = Head;
   Command[4] = Sector;
   Command[5] = 0x02;
   Command[6] = 0x12;
   Command[7] = 0x18;
   Command[8] = 0x00;

   for (ULONG i = 0; i < 9; i++)
      FdcWriteByte(Command[i]);
   WRITE_PORT_UCHAR(FDC_DOR, 0);
}