// Actual vertical and horizontal scan line
// High byte (08-15): vertical scanline
// Low byte  (00-07): horizontal scanline
// Note: We need only MSB
volatile UBYTE* REG_VHPOSR_MSB = (UBYTE *) 0xDFF006;

// PAL uses 320x256
// But it is better for games to use the NTSC resolution 320x200 (e.g. scan lines fits a byte)
// which most games of the era used
#define SCANLINE_FIRST_INDEX 0x2C  // (44)
#define SCANLINE_NTSC_LAST_INDEX (SCANLINE_FIRST_INDEX + 199)
#define SCANLINE_PAL_LAST_INDEX (SCANLINE_FIRST_INDEX + 255)

void waitVBLANK()
{
    while ( *REG_VHPOSR_MSB != (UBYTE)( SCANLINE_NTSC_LAST_INDEX + 1 ) )
    {
    }
}