ATB2W
ATB2W(OSCANCOLOR, 0x00);
ATB2W(HORPIXPAN, ((startadd & 0x00000003) << 1));
ATB2W(MODECTL, 0x01);
ATB2W(HORPIXPAN, ((startadd & 0x00000003) << 1));
ATB2W(MODECTL, 0x01);
ATB2W(HORPIXPAN, ((startadd & 0x00000003) << 1));